W3186: Variability, Adaptation, and Management of Nematodes Impacting Crop Production and Trade

(Multistate Research Project)

Status: Inactive/Terminating

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SAES-422 Reports

Annual/Termination Reports:

[12/18/2013] [02/11/2015] [02/15/2016] [01/19/2017] [01/11/2018]

Date of Annual Report: 12/18/2013

Report Information

Annual Meeting Dates: 11/14/2013 - 11/15/2013
Period the Report Covers: 10/01/2012 - 09/01/2013

Participants

Adams, Byron (bjadams@byu.edu) - Brigham Young University;
CaswellChen, Edward (epcaswell@ucdavis.edu) - University of California, Davis;
Chen, Senyu (chenx099@umn.edu) - University of Minnesota;
Elling, Axel (elling@wsu.edu) - Washington State University;
Hafez, Saad (shafez@uidaho.edu) - University of Idaho;
Ingham, Russell (inghamr@science.oregonstate.edu) - Oregon State University;
Klink, Vincent (vk85@msstate.edu) - Mississippi State University;
Lawrence, Gary (glawrence@entomology.msstate.edu) - Mississippi State University;
Lawrence, Kathy (lawrekk@auburn.edu) - Auburn University;
Melakeberhan, Haddish (melakebe@msu.edu) - Michigan State University;
Pudasaini, Mahesh (maheshp@uidaho.edu) - University of Idaho;
Powers, Thomas (tpowers1@unl.edu) - University of Nebraska;
Robbins, Robert (rrobbin@uark.edu) - University of Arkansas;
Roberts, Philip (philip.roberts@ucr.edu) - University of California, Riverside;
Sipes, Brent (sipes@hawaii.edu) - University of Hawaii;
Thomas, Stephen (stthomas@nmsu.edu) - New Mexico State University;
Thompson, David (dathomps@nmsu.edu) - New Mexico State University;
Zasada, Inga (Inga.Zasada@ars.usda.gov) - USDA-ARS Oregon;

Brief Summary of Minutes

W-3186
REGIONAL PROJECT
Variability, Adaptation, and Management of Nematodes Impacting Crop Production and Trade

2013 ANNUAL MEETING
Honolulu, HI
November 14 - November 15, 2013

Agenda

Wednesday November 13:
Arrivals (contact B. Sipes or taxi which is probably $30 to $35) to Lincoln Hall on the UH Manoa campus.

Thursday November 14:

8:00 a.m. to 5:00 p.m. Gilmore Hall 311. Walk from Lincoln Hall the 1 block to Gilmore Hall. A continental breakfast including coffee, pastry, juice and fruit will be available.

8:30 a.m. Welcome and introductions (W-3186 Chair, Kathy Lawrence Presiding)

8:40 a.m. Welcome and instructions (W-3186 Host, Dr. Brent Sipes)

8:50 p.m. Welcome (Maria Gallo, Dean College of Tropical Agriculture and Human Resources)

9:00 a.m. Summary of the new project (Dr. Phil Roberts)

9:30 a.m. Project overview: Dr. David Thompson, Administrative Advisor, Associate Dean and Director, Agricultural Experiment Station, New Mexico State University. Skype in by

10:00 a.m. Begin annual report presentations
Kathy Lawrence -Alabama
Phil Roberts- California
Ed Caswell-Chen - California
Brent Sipes Hawaii
Gary Lawrence - Mississippi
Haddish Melakeberhan - Michigan
Tom Powers - Nebraska
Steve Thomas New Mexico
Russell E. Ingham Oregon
Inga Zasada Unsure
Axel Elling - Washington

Noon Lunch (box lunches)

1:00 p.m. Report presentations

3:00 p.m. Break

5:00 p.m. Instructions for dinner (Dr. Brent Sipes). Return to the hotel

6:00 p.m. Meet in the lobby and drive to Nico's Pier 38 for dinner

Friday November 15:

8:00 a.m. to Noon. Gilmore Hall 311. Breakfast Good morning welcome and daily updates (W-3186 Host, Brent Sipes)

8:15 a.m. Continuation of reports: Graduate student reports.

10:00 a.m. Morning break

10:30 a.m. Business Meetings (Chair, Presiding):
Increasing membership
Joint proposals
Annual report preparations
Meeting site selections for 2015 and 2016
Election of Secretary
Other matters

Noon-1 p.m. Lunch (boxes provided)

1:00 p.m. Adjourn

Afternoon departures

Accomplishments

Objectives: Objective 1: Characterize genetic and biological variation in nematodes relevant to crop production and trade. Idaho: During the survey, a total of 128 samples from different mint growing areas in Nampa, Wilder, Caldwell, Marsing, Fruitland, Nyssa, Emmett, and Ontario were analyzed. Out of 128 samples, 120 samples contained root lesion nematode, 44 samples contained root-knot nematode, 97 samples contained spiral nematode, and 112 samples contained pin nematode. Similarly, sheath nematode found in 2 samples, dagger nematode in 5 samples, ring nematode in 5 samples, and stubby root nematode in 9 samples. County wise, 115 samples were surveyed in Canyon, 11 in Malheur, and two in Gem. Nematode were recorded in the range of 10-2750 for root lesion nematode, 10-6900 for root knot nematode, 10-6550 for spiral nematode, and 30-67200 for pin nematode per 500 cc soil sample. As mint is also rotated with other crops, survey for three growing seasons is necessary to obtain the ecological diversity of nematodes associated with commercial mint. Mississippi: Functional analysis of Glycine max genes identified from its resistant reaction to its major parasitic nematode pathogen, Heterodera glycines. Tests are in process to identify genes that are involved in the resistance of Glycine max (soybean) to the Heterodera glycines (soybean cyst nematode [SCN]). To identify these genes involves isolation of syncytia cells formed by SCN that are undergoing compatible or incompatible reactions at different times during the reactions. The RNA was isolated from these cells and used in comparative gene expression analyses. Candidate resistance genes were identified and then genetically engineered into soybean plants that are normally susceptible to SCN. The results from examining the function of 62 candidate genes demonstrate that some of the genes play a role in resistance. Further experimentation is ongoing to understand the details of the process of resistance. Mississippi: The use of RNAi in functional analyses of soybean genes involved in suppressing soybean cyst nematode (SCN) infection. The interaction between soybean and the soybean cyst nematode (SCN) results in a 7-10% decrease in production worldwide. The SCN is capable of inducing the formation of multinucleate feeding structure known as a syncytium that is the site of parasitism. Syncytia undergoing an incompatible reaction to SCN parasitism were analyzed for gene expression that is active specifically during the incompatible reaction. These genes were then expressed in a susceptible genotype (Williams 82). Two genes, MSU12-1 and MSU13-1, when expressed to high levels in the susceptible Williams 82 genotype resulted in suppressed SCN infection. To confirm that the gene was involved in suppressing SCN infection, MSU12-1 and MSU13-1 was engineered as RNAi constructs into Peking/PI 548402 which is a genotype that is normally resistant to SCN. RNAi is used to decrease the normal RNA levels of a target gene, acting as a hypomorphic condition. As hypothesized, SCN growth is increased significantly in these roots where MSU12-1 and MSU13-1 gene activity is suppressed. The combination of overexpression and RNAi in the high throughput gene testing pipeline is a useful tool in examining the function of large numbers of candidate genes. Washington: Meloidogyne chitwoodi is a significant threat to the potato industry in the Pacific Northwest. The goal of this project is to analyze the phylogeographic relationships of M. chitwoodi populations. This is significant because it will aid in developing more durable M. chitwoodi resistance and improve M. chitwoodi diagnostics. Since the last reporting period we have studied the morphological and molecular variability of four M. chitwoodi isolates representing distinct races/pathotypes. Using a canonical discriminant analysis it was found that stylet length is the least variable morphological character in females. Perineal patterns were significantly more variable than reported in the original species description. Washington: Each of the four M. chitwoodi races/pathotypes showed species-characteristic isozyme patterns (Mdh: N1a, Est: S1, Sod: H1). Nuclear ribosomal DNA sequences amplified with the diagnostic primer sets 194/195 and JMV1/JMV2/JMVhapla were stable across the M. chitwoodi isolates analyzed here. In contrast to conserved nuclear markers a high level of variability was detected in mitochondrial DNA (mtDNA). To study the genetic structure of M. chitwoodi, regions of the COII, tRNA-His and 16S rRNA mtDNA genes were amplified using single second-stage juveniles. For each individual, five clones were sequenced and a minimum-spanning haplotype network was developed. It was found that even though all M. chitwoodi races/pathotypes share one dominant mtDNA haplotype, there are certain haplotypes that were overrepresented in certain M. chitwoodi races/pathotypes. Nebraska: A set of experiments were conducted with the cytochrome oxidase subunit 1 (COI) primers to test haplotype and nucleotide diversity in Heterodera and Meloidogyne species. The primer set amplified a 721-724bp fragment for of COI in Meloidogyne and 862bp for Heterodera. For Heterodera glycines COI from 82 specimens collected from 8 U.S. states were amplified and sequenced. Geographic location of the samples ranged from Delaware to central Nebraska, and Alabama to Minnesota. Only 4 different haplotypes were observed. Overall nucleotide diversity was 0.19%. Most collection sites had a single common haplotype (0 haplotype diversity) which was widely distributed across the U.S. A second haplotype was observed in 7 counties in Minnesota and a single county in northeast Nebraska. To date there are no known physiological differences among the different haplotypes. On a smaller geographic scale only two haplotypes were recorded among 20 specimens of the sugar beet cysts nematode, Heterodera schachtii collected in two states with a nucleotide diversity of 0.05%. Nebraska: For Meloidogyne species, a range of within species diversity was recorded. At the lowest level, no haplotype diversity was observed in the COI nucleotide sequence for M. chitwoodi collected from three states. Forty-seven specimens of the M. javanica/arenaria/incognita complex from 12 states produced 4 haplotypes and 0.02% nucleotide diversity. In contrast, 28 specimens of M. hapla from 11 states produced 11 haplotypes and a nucleotide diversity of 1.21%. The nucleotide and haplotype diversity observed in M. hapla was similar to undescribed species of Mesocriconema from native North American grasslands. This suggests that M. hapla may be native to North America whereas M. chitwoodi may be an exotic invasive species in North America. Hawaii: Pratylenchus have been reported across the tropics and subtropics. A molecular identification of root-lesion nematode populations from across Thailand and Hawaii was undertaken. Pratylenchus were obtained from banana (Thailand) and corn (Hawaii). The D2-D3 expansion region of 28S rDNA was amplified and sequenced. The majority of the isolates were identified as P. coffeae followed by P. brachyurus and then P. speijeri. New Mexico: In 2013 work was initiated to improve the capability for using molecular tools to differentiate Ditylenchus species of regulatory concern from more benign soil-inhabiting species. Plant and soil samples thought to contain one or more species of Ditylenchus were obtained from WA, OR, NE, and ID. Additional samples are pending from SC, WI, and the Philippines. Nematodes recovered from these samples were lysed following procedures by Solano, 2013 (Ph.D. dissertation, New Mexico State University), after which 18S rDNA was amplified using 18sF (5-GAAACCGCGAACGGCTCA-3) and 18sR (5-AACTAAGAACGGCCATGCACC-3) primers (Solano 2013, Ph.D. thesis) which were shown to be more universal than the previous standard primer set of SSU18a and SSU26r (Floyd et. al., 2002) in previous studies in our lab. The ITS/5.8S rDNA region was also amplified with primers ITSF (5-CGCAGTGGCTTGA ACCGG-3) and 528S R (5-CGCCGACTCTATCCGTTTCCACC-3) (Solano 2013, Ph.D. thesis). The 100% success rate for the 56 samples analyzed to date suggests that the proposed approach will be highly productive for generating a robust sequence library for Ditylenchus from around the world that is unlikely to have holes from samples that could not be characterized using this approach. Alabama: Reniform nematode (Rotylenchulus reniformis) resistance in the cotton LONREN-1 x FM966 breeding lines developed at Auburn University have demonstrated that reniform resistance is accompanied by severe plant intolerance limiting plant growth and yields. The objective of this study was to evaluate effects of applying nematicides to selected reniform nematode resistant breeding lines to reduce the intolerance symptoms. Four resistant breeding lines from the LONREN-1xFM966 cross, the germplasm lines LONREN-1 and BARBREN 713, one susceptible line from the LONREN-1xFM966 cross, and the susceptible cultivar DP393 were treated with nematicides and their performances evaluated. In the greenhouse, nematicides increased plant heights in resistant lines. Nematicides further reduced reniform populations in the resistant lines 45 days after planting (DAP). Reniform populations were 50% lower in resistant lines compared to the susceptible lines by the end of the growing period. In microplot and field trials, the phenotypic stunting response of resistant lines was reduced by nematicides with increased plant heights at 30 and 75 DAP. Nematicides reduced early season R. reniformis populations in the microplot trial by 41%. By harvest, R. reniformis populations in microplot and field trials were 54 and 52%, respectively, higher in the susceptible lines compared to resistant lines. Egg populations in the field trial at 100 DAP were 84% lower in resistant lines compared to susceptible checks. Seed cotton yields in the field trial were increased by nematicides to levels that were comparable to susceptible checks. Objective 2: Determine nematode adaptation processes to hosts, agro-ecosystems and environments. Michigan: Reducing the impact of sugar beet cyst nematode (SBCN), through use of mustard and radish as resistant-, cover-, green manure- and/or trap-crops, and improving soil health (organic matter, biological, physiochemical, nutritional and water holding priorities) are two of the critical research priorities for the Michigan Sugar Beet Industry (MSC). However, consistent suppression of SBCN and increase of crop yield from use of these crops has been elusive due to many factors. These include lack of integrated knowledge on the performance of these crops in different soil conditions and their impact on other plant-parasitic nematodes (PPN) of economic significance in the sugar beet production landscape. On-going are studies to identify and understand these complex relationships using resistant and susceptible of each of radish (Defender and Tillage), mustard (Pacific Gold and Ida Gold) and soybean (92Y80 and 92M91), respectively, and SBCN-tolerant (BTS18RR4N) and susceptible (BTS10RR34) sugar beet along with corn (P9910R) as controls in Loamy and Sandy loam soils. Preliminary analyses indicate similar population densities of cysts and root-lesion (Pratylenchus spp.) nematodes in the pairs of resistant/tolerant and susceptible crops in both fields, but more variable soil food web structure by field and across crops than within crops. Overall, the data support the hypothesis that there are distinct interactions among the crops, SBCN and soil conditions. Idaho: To determine the onset of wilt, pathogenicity and interaction of Verticillium and mint nematodes, a greenhouse experiment was established. The experiment includes seven treatments with untreated control. Plants were inoculated with Pratylenchus penetrans, P. neglectus (lesion nematode), Verticillium dahliae, Pratylenchus penetrans + Verticillium dahliae, P. neglectus + Verticillium dahliae, Pratylenchus penetrans + P. neglectus + Verticillium dahliae. Data obtained from a greenhouse experiments on interaction of predominant species of lesion nematodes and Verticillium dahliae on the mint has been analyzed. Interactive effect of V. dahliae and lesion nematodes seems an additive on mint hay yield in the greenhouse experiment. Verticillium dahliae alone caused 44 % damage in mint hay yield. Root lesion nematode Pratylenchus neglectus seems pathogenic to mint. A 23 and 46 % reduction on mint hay were caused by P. neglectus alone or in combination with V. dahliae, respectively. P. penetrans alone caused 44 % yield reduction of mint hay while combination of P. penetrans and V. dahliae killed almost all plants (98%). Population of P. penetrans is increased by 41 fold which indicates that mint is an excellent host for P. penetrans. The experiment will be repeated one more times with necessary modifications based on the outcome of this experiment to confirm the results. New Mexico: An as yet undetermined species of Meloidogyne that was recovered from purple nutsedges in two field locations in Dona Ana County, NM in 2012 was tested against the major crops produced in southern NM. Non-host crops for this root-knot nematode include: cotton, chile pepper, corn, sorghum, alfalfa, onion, tomato, and winter rye. Additional poor hosts upon which small amounts of nematode reproduction were observed include: oat, wheat, and perennial ryegrass. Initial nematode populations doubled in 45 days on bentgrass and barley. Yellow nutsedge (Cyperus esculentus) and purple nutsedge (C. rotundus) were the best hosts for this nematode, resulting in population increases of over 26-fold on yellow nutsedge and over 5-fold on purple nutsedge after 45 days. New Mexico: A study was established to determine the effect of previous crop on subsequent M. incognita reproduction on yellow and purple nutsedges. Such information is necessary for accurate prediction of the extent to which different cropping scenarios will impact root-knot nematode carryover to future crops from perennial weeds. Both nutsedges were inoculated with eggs recovered from cotton, chile, or corn (the major summer annual crops in southern NM). Inoculum from tomato was also included to allow extrapolation to results from previous studies. The experiment will be harvested upon accumulation of 750 heat units (DD24), and eggs extracted from roots. Inoculum viability from each source was determined over 22 days post-inoculation with the following results: cotton (22.1%); chile pepper (57.7%), corn (14.0%), tomato (56.2%). Inoculum viability will be used to normalize final egg recovery from nutsedges. Objective 3: Develop and assess nematode management strategies in agricultural production systems. Michigan: In order to develop integrated and scalable management strategies in diverse production systems and across climatic zones, the relationships of agricultural input- (temperate) and broad anthropogenic-driven (tropical) changes are being investigated. Preliminary analysis of the effects of plant- and animal-based organic and non-organic soil amendment application in mineral soils on carrot quality and yield, soil physiochemical properties, nematode community, and overall soil quality of fresh market and processing carrot cultivars mostly show cultivar-specific responses. On-going are studies to understand the relationships among biological, physiochemical and nutritional degradations in selected sub-Saharan Africa soil groups (order), plates that hold the ecosystem change footprints of land use practices. Preliminary analyses show close relationships between biological degradation and land use practices, but differing by soil group and climatic zones, potentially leading to identifying specificity of biological and physiochemical associations in production soils. Mississippi: Quantitative field testing Heterodera glycines from metagenomic DNA samples isolated directly from soil under agronomic production. A quantitative PCR procedure targeting the Heterodera glycines ortholog of the Caenorhabditis elegans uncoordinated-78 gene determined their number from metagenomic DNA samples isolated directly from field soil under agronomic production. This outcome was in the presence of other soil dwelling plant parasitic nematodes including Hoplolaimus, predatory nematodes including Mononchus, free-living nematodes and biomass. The methodology provides a framework for molecular diagnostics of nematodes from metagenomic DNA isolated directly from field soil. Hawaii: Reniform and burrowing nematodes are chronic problems in many crops. Growers require environmentally sound post-plant treatments to augment preplant management tactics to manage these nematodes. Avermectin, thiophanate-methyl, spinosad, spirotetramat, and imidacloprid are possible alternatioves. Spinosad, spirotetramat, and thiophanate-methyl show possible benefits by decreasing nematode populations and increasing plant growth. These products may provide postplant treatment options that can aid in the management of anthurium decline. New Mexico: Grape yield and rate of M. incognita population recovery in a commercial vineyard was measured following spring and fall treatment with 200 ppm Cordon® (an emulsifiable formulation of 1,3-dichlorpropene) in 2011 and 2012. The 12 year old vineyard has a history of 50% reduction in cabernet sauvignon tonnage associated with root-knot nematode injury beginning the fifth year after establishment. In spring 2013 M. incognita JS numbers remained at 25% of threshold density in treated plots compared to five times threshold density in untreated plots. Yield in treated plots was 8% greater than untreated plots, and fall JS numbers in treated plots had resurged to 50% of numbers in untreated plots. In a related study that evaluated M. incognita population development in grass varieties being considered for use as understory crops in vineyards, all nine fine fescue varieties were excellent hosts for the nematode (RF values ranging from 13.0 to 41.2). However, perennial ryegrass (SR 4650) and Jesup (Max-Q) tall fescue supported far fewer nematodes (RF = 2.7 for perennial ryegrass; mean RF = 1.9 for tall fescue, with 60% of plants exhibiting RF < 0.1). Evaluation of M. incognita reproduction on different brassicaceous crops being considered for use as biofumigants in organic chile pepper production found that all three mustard varieties exhibited RF values between 13.2 and 28.3, and should be considered good hosts for southern root-knot nematode. Broccoli cultivar Arcadia, however was a poor host for the nematode, with a mean RF value of 0.4. Alabma: Five nematicide combinations were evaluated for Meloidogyne incognita (Root-knot nematode) and Rotylenchulus reniformis (Reniform nematode) management on three cotton varieties at different locations across Alabama. The field sites were located at the Plant Breeding Unit (PBU) of the E.V. Smith Research Center near Tallassee and the Tennessee Valley Research and Extension Center (TVREC) near Belle Mina. The cotton varieties were treated with nematicide seed treatments. Temik 15G was applied at planting with granular hoppers attached to the planters and Vydate was applied as a foliar spray at the six- to eight-leaf stage. Nematode samples were taken at 45 and 85 days after planting at the PBU and at 35 and 65 days after planting at the TVREC. Statistically no interaction occurred between the varieties and the nematicides at either location. In both locations FM 1740 B2F supported a greater stand counts compared to the Stoneville varieties; also seed cotton yield was significantly greater in the Stoneville varieties compared to the FM 1740 B2F. The two locations differ in the ranking of nematicide effectiveness. At the PBU, Temik 15G produced the greatest average seed cotton yield at 4,488.4 kg/ha in two of the three varieties followed by Aeris seed treatment which produced an average of 3,735 kg/ha. However, at the TVREC, Vydate CLV produced the greatest seed cotton yield at 3445.8 kg/ha in two of the three varieties followed by Temik 15G at 3067 kg/ha and then the seed treatments. The nematicides increased the seed cotton yields on two of the three varieties but did produce enough additional lint yields to pay for the additional nematicide investment.

Publications

Al-Hammouri, A., W .Lindemann, S. Sanogo, S.Thomas, and R. Steiner. 2013. Interaction between Rhizoctonia solani and Meloidogyne incognita on chile pepper in soil infested simultaneously with both plant pathogens. Canadian Journal of Plant Science 93:67-69. Alemayehu Habteweld, D. Brainard, M. Ngouajio, S. Kravchenko, and H. Melakeberhan (2013). Assessing the impact of compost amendment for managing nematodes and soil health in mineral soil to improve carrot production. 52nd Annual Meeting of the Society of Nematologists Meeting, Knoxville, Tennessee. Bai, X., B. J. Adams, T. A. Ciche, S. Clifton, R. Gaugler, K.-s. Kim, J. Spieth, P. W. Sternberg, R. K. Wilson, and P. S. Grewal. 2013. A Lover and a Fighter: The Genome Sequence of an Entomopathogenic Nematode Heterorhabditis bacteriophora. PLoS ONE 8:e69618. Bailey, David, K. S. Lawrence, and D. S. Schrimsher. 2013. Evaluation of seed treatment nematicides on soybeans for reniform management in north Alabama, 2012. Report 7: N003. DOI:10.1094/PDMR07. The American Phytopathological Society, St. Paul, Minnesota. Bailey, David, K. S. Lawrence, and D. S. Schrimsher. 2013. Evaluation of seed treatment nematicides on soybeans for root knot management in central Alabama, 2012. Report 7: N001. OI:10.1094/PDMR07. The American Phytopathological Society, St. Paul, Minnesota. Bailey, David, K. S. Lawrence, and D. S. Schrimsher. 2013. Soybean variety response to reniform nematodes in north Alabama, 2012. Report 7: N002. DOI:10.1094/PDMR07. The American Phytopathological Society, St. Paul, Minnesota. Bailey, David, K. S. Lawrence, and D. S. Schrimsher. 2013. Valent soybean seed treatment evaluation for reniform management in north Alabama, 2012. Report 7: N004. DOI:10.1094/PDMR07. The American Phytopathological Society, St. Paul, Minnesota. Bennett, Rebecca S., Tamara Z. Scott, Katheryn S. Lawrence, and Gary W. Lawrence. 2013. Sequence characterization of race 4-like isolates of Fusarium oxysporum from Alabama and Mississippi. Journal of Cotton Science 17:1-6. Bennett, Rebecca S., Tamara Z. Scott, Katheryn S. Lawrence, and Gary W. Lawrence. 2013. Sequence characterization of race 4-like isolates of Fusarium oxysporum from Alabama and Mississippi. Journal of Cotton Science 17:1-6. Castillo, J. D., Lawrence, K. S., and Kloepper, J. W. 2013. Biocontrol of the reniform nematode by Bacillus firmus GB-126 and Paecilomyces lilacinus 251 on cotton. Plant Disease 97:967-976. Castillo, J.D., D. Schrimsher, and K. Lawrence. 2012. Effect of Bacillus firmus GB-126 against Rotylenchulus reniformis, Meloidogyne incognita, and Heterodera glycines under in vitro and greenhouse conditions. Journal of Nematology 44: 456-457. de Tomasel, C. M., B. J. Adams, F. G. Tomasel, and D. H. Wall. 2013. The life cycle of the Antarctic nematode Plectus murrayi under laboratory conditions. Journal of Nematology 45:39-42. Gutt, J; Adams, B; Bracegirdle, T; Cowan, D; Cummings, V; di Prisco, G; Gradinger, R; Isla, E; McIntyre, T; Murphy, E; Peck, L; Schloss, I; Smith, C; Suckling, C; Takahashi, A; Verde, C; Wall, DH; Xavier, J. 2012. Antarctic Thresholds - Ecosystem Resilience and Adaptation: a new SCAR-Biology Programme. Polarforschung, 82, 2, 147-150, hdl:10013/epic.42531.d001 (erschienen 2013) http://aurora.auburn.edu/repo/bitstream/handle/11200/44167/CottonResearchReport2012.pdf?sequence=2 Humphreys-Pereira, D.A. and Elling, A.A. 2013. Intraspecific variability and genetic structure in Meloidogyne chitwoodi from the USA. Nematology 15:315-327. K. Vijay Krishna Kumar, S. KR. Yellareddygari, M. S. Reddy, J. W. Kloepper, K. S. Khairy M. Soliman, Ernst Cebert, and Govind C. Sharma. 2013. 18S and ITS1 Genomic Sequence Variations in Rotylenchulus reniformis Isolates from Alabama. Journal of Cotton Science 17:184194. Klink VP, Lawrence GW, Lawrence KS. 2013. Engineered soybean cyst nematode resistance. Ch. 6: 139-172. in Soybean - Pest Resistance. Ed. HA El-Shemy. Intech Publishers. ISBN 978-953-51-0978-5. Klink VP, Matsye PD, Lawrence KK, Lawrence GW. Engineered soybean cyst nematode resistance. Intech Publishers. "Soybean - A Review / Book 1", ISBN 980-953-307-542-1. Klink VP, Matsye PD, Lawrence KK, Lawrence GW. Engineered soybean cyst nematode resistance. Intech Publishers. "Soybean - A Review / Book 1", ISBN 980-953-307-542-1 Klink, V.P., G.W. Lawrence and K.S. Lawrence 2013 Engineered sobean cyst nematode resistance, Ch 6: 139-172. In Soybean Pest Resistance, Ed: HA EL-Shemy, Intech Publishers ISBN 978-953-51-0978-5. Lawrence, K. S. and G. W. Lawrence. 2013. Holistic Crop Management Systems in Reniform Nematode Infected Fields. Proceeding of the XXXI Congress of Brazilian Nematology Vol.1:33-34. Lawrence, K. S. and G. W. Lawrence. 2013. Holistic Crop Management Systems in Reniform Nematode Infected Fields. Proceeding of the XXXI Congress of Brazilian Nematology Vol.1:33-34. Lawrence, K. S., C. D. Monks, and D. Delaney. Eds. 2012 AU Crops: Cotton Research Report. March 2013. Alabama Agricultural Experiment Station Research Report Series No. 42. Lawrence, K.S., D.W, Schrimsher, and Chet Norris. 2013. Fungicide combination evaluations for cotton seedling disease management in north Alabama, 2012. Report 7: ST011. DOI: 10.1094/PDMR07. The American Phytopathological Society, St. Paul, MN. Lawrence, K.S., D.W, Schrimsher, and S. Nightengale. 2013. Cotton variety and nematicide combinations for root knot management in south Alabama, 2012. Report 7: N013. DOI: 10.1094/PDMR07. The American Phytopathological Society, St. Paul, MN. Lawrence, K.S., D.W, Schrimsher, and S. Nightengale. 2013. Cotton seed treatment, granular and foliar nematicide combinations for root knot management in Alabama, 2012. Report 7: N011. DOI: 10.1094/PDMR07. The American Phytopathological Society, St. Paul, MN. Lawrence, K.S., D.W, Schrimsher, C. H. Burmester, and Chet Norris. 2013. Seed quality and fungicides combinations for seedling disease management in north Alabama, 2012. Report 7: ST010. DOI: 10.1094/PDMR07. The American Phytopathological Society, St. Paul, MN. Lawrence, K.S., D.W, Schrimsher, C. H. Burmester, and Chet Norris. 2013. Cotton variety and nematicide combinations for reniform management in north Alabama, 2012. Report 7: N014. DOI: 10.1094/PDMR07. The American Phytopathological Society, St. Paul, MN. Lawrence, K.S., D.W, Schrimsher, C. H. Burmester, and Chet Norris. 2013. Cotton seed treatment, granular, and foliar nematicide combinations for reniform management in north Alabama, 2012. Report 7: N012. DOI: 10.1094/PDMR07. The American Phytopathological Society, St. Paul, MN. Lawrence, M. E. Miller, H. Sudini, E.C. Surendranatha Reddy, X. G. Zhou and D. E. Groth. 2013. Ultrastructural studies on the interaction between Bacillus subtilis MBI 600 (Integral®) and the rice sheath blight pathogen, Rhizoctonia solani. African Journal of Microbiology Research Vol. 7:2078-2086. Levy, J., W. Berry Lyons, and B. Adams. 2013. Understanding Terrestrial Ecosystem Response to Antarctic Climate Change. Eos, Transactions American Geophysical Union 94:33-33. Maung, Zin Thu Zar, S. Yildiz, T. Teal, J. Gronseth, C. Kwoseh, T. Adjeigyapong, V. Saka, M. Lowole, G.N. Karuku, P.M. Wachira, J.W. Kimenju, J. Qi, T. Schmidt, and H. Melakeberhan (2013). Abundance and frequency of nematodes in Ferralsol, Lithosol and Nitosol soil groups in Ghana, Kenya and Malawi. 52nd Annual Meeting of the Society of Nematologists Meeting, Knoxville, Tennessee. Maung, Zin Thu Zar, S. Yildiz, T. Teal, J. Gronseth, C. Kwoseh, T. Adjeigyapong, V. Saka, M. Lowole, G.N. Karuku, P.M. Wachira, J.W. Kimanju, J. Qi, T. Schmidt, and H. Melakeberhan (2013). Nematode community analyses to assess the food web structure and ecological disturbances in Ferralsol, Lithosol and Nitosol soil groups in Ghana, Kenya and Malawi. 52nd Annual Meeting of the Society of Nematologists Meeting, Knoxville, Tennessee. Melakeberhan, H. and Wang, W. (2013). Proof-of-concept for managing Meloidogyne hapla parasitic variability in carrot production soils. Nematology, 15: 339-346. Melakeberhan, H., Z.T.Z. Maung, S. Yildiz, T. Teal, J. Gronseth, C. Kwoseh, T. Adjeigyapong, V. Saka, M. Lowole, G.N. Karuku, P.M. Wachira, J.W. Kimenju, J. Qi and T. Schmidt (2013). Types of biological and nutritional degradations in Ferralsol, Lithosol, and Nitosols soild groups in Ghana, Kenya and Malawi. 52nd Annual Meeting of the Society of Nematologists Meeting, Knoxville, Tennessee. Moore, S. R. and K. S. Lawrence. 2013. The effect of soil texture and irrigation on Rotylenchulus reniformis I and cotton. Journal of Nematology 45:99-105. Nyaku ST, Sripathi VR, Kantety RV, Gu YQ, Lawrence K, et al. (2013) Characterization of the Two Intra-Individual Sequence Variants in the 18S rRNA Gene in the Plant Parasitic Nematode, Rotylenchulus reniformis. PLoS ONE 8(4): e60891. doi:10.1371/journal.pone.0060891. R.Y.M. Cabos, B.S. Sipes, C. Nagai, M. Serracin, and D.P. Schmitt. 2012. Host plant resistance for nematode control in coffee. 51st Annual Meeting of the Society of Nematologists. Savannah, GA. R.Y.M. Cabos, K.-H. Wang, B.S. Sipes, W. Heller, and T. Matsumoto. 2013. Detection of plant-parasitic nematode DNA in the gut of predatory and omnivorous nematodes. Nematropica 43: 44-48. Rothrock C. S., S. A. Winters, J.D. Barham, Alan B. Beach, Melanie B. Bayles, P. D. Colyer, T. Kelley, R. C. Kemerait, G.W. Lawrence, K. S. Lawrence, G.B. Padgett, P. M. Phipps, G. L. Sciumbato, R. Thacker, and J. E. Woodward. 2013. Report of the Cottonseed Treatment Committee for 2012. Proceedings of the Beltwide Cotton Conference, Vol. 1:157-164. National Cotton Council of America, Memphis, Tennessee. http://www.cotton.org/beltwide/proceedings/2005-2013/index.html Rothrock C. S., S. A. Winters, J.D. Barham, Alan B. Beach, Melanie B. Bayles, P. D. Colyer, T. Kelley, R. C. Kemerait, G.W. Lawrence, K. S. Lawrence, G.B. Padgett, P. M. Phipps, G. L. Sciumbato, R. Thacker, and J. E. Woodward. 2013. Report of the Cottonseed Treatment Committee for 2012. Proceedings of the Beltwide Cotton Conference, Vol. 1:157-164. National Cotton Council of America, Memphis, Tennessee. http://www.cotton.org/beltwide/proceedings/2005-2013/index.html Sanogo, S., J. Schroeder, S. Thomas, L. Murray, N. Schmidt, J. Beacham, C. Fiore, and L. Liess. 2013. Weed species not impaired by Verticillium dahliae and Meloidogyne incognita realationships that damage chile pepper. Plant Health Progress doi:10.1094/PHP-2013-0920-01-RS. Schrimsher, D.W, and K.S. Lawrence. 2013. Evaluation of Aeris, Temik, and two experimental compounds for management of reniform nematodes on cotton in north Alabama, 2012. Report 7: N008. DOI: 10.1094/PDMR07. The American Phytopathological Society, St. Paul, MN. Schrimsher, D.W, and K.S. Lawrence. 2013. Evaluation of Poncho Votivo, Aeris, and Temik on cotton for reniform nematode management in north Alabama, 2012. Report 7: N007. DOI: 10.1094/PDMR07. The American Phytopathological Society, St. Paul, MN. Seloame T. Nyaku, Ramesh V. Kantety, Yonathan Tilahun, Kathy S. Lawrence, Smith, Randy, Gary W. Lawrence, Kathy S. Lawrence, Richard Harkess and Carolyn Conger. 2013. Growth and Development of Five Upland Cotton (Gossypium hirsutum) Varieties in Reniform (Rotylenchulus reniformis) Infested Soils. Proceedings of the Beltwide Cotton Conference, Vol. 1:123-128. National Cotton Council of America, Memphis, Tennessee. http://www.cotton.org/beltwide/proceedings/2005-2013/index.html Smith, Randy, Gary W. Lawrence, Kathy S. Lawrence, Richard Harkess and Carolyn Conger. 2013. Growth and Development of Five Upland Cotton (Gossypium hirsutum) Varieties in Reniform (Rotylenchulus reniformis) Infested Soils. Proceedings of the Beltwide Cotton Conference, Vol. 1:123-128. National Cotton Council of America, Memphis, Tennessee. http://www.cotton.org/beltwide/proceedings/2005-2013/index.html Thomas, Stephen, J.M. Beacham, L. Holland, J. Schroeder, E. Morris, N. Schmidt, L. Murray, F. Solano-Campos, S. Hanson, and J.D. Eisenback. 2013. Observations regarding a presently-undetermined Meloidogyne species parasitizing yellow and purple nutsedges. Journal of Nematology 45 (in press). Vetter, J., Z. Ou, L. Murray, S.H. Thomas, and J. Schroeder. 2013. Determining the effectiveness of including spatial information into a nematode/nutsedge pest complex model. Proceeding of the 24th Annual Kansas State University Conference on Applied Statistics in Agriculture: 109-124. Wallace, Ted P., P. M. Thaxton, Bobby Golden, G. W. Lawrence, Jodi Scheffler, K. S Lawrence, David Weaver and Roelof B. Sikkens. 2013. Agronomic Performance of Barbadense and Longicalyx Derived Breeding Lines. Proceedings of the Beltwide Cotton Conference, Vol. 1:1005. National Cotton Council of America, Memphis, Tennessee. http://www.cotton.org/beltwide/proceedings/2005-2013/index.html Wallace, Ted P., P. M. Thaxton, Bobby Golden, G. W. Lawrence, Jodi Scheffler, K. S Lawrence, David Weaver and Roelof B. Sikkens. 2013. Agronomic Performance of Barbadense and Longicalyx Derived Breeding Lines. Proceedings of the Beltwide Cotton Conference, Vol. 1:1005. National Cotton Council of America, Memphis, Tennessee. http://www.cotton.org/beltwide/proceedings/2005-2013/index.html Wheeler, T. A., K. S. Lawrence, D. O. Porter, W. Keeling, and B. G. Mullinix, Jr. 2013. The relationship between environmental variables and response of cotton to nematicides. Journal of Nematology 45: 8-16. Xiang, N., K.S. Lawrence, D. Schrimsher, and S. Nightengale. 2013. Evaluation of Temik, Aeris, and two experimental compounds on cotton for root knot management in Alabama, 2012. Report 7: N006. DOI: 10.1094/PDMR07. The American Phytopathological Society, St. Paul, MN. Xiang, N., K.S. Lawrence, D. Schrimsher, and S. Nightengale. 2013. Evaluation of Poncho Votivo, Aeris, Temik, and UFS0 738 on cotton for root knot management in Alabama, 2012. Report 7: N005. DOI: 10.1094/PDMR07. The American Phytopathological Society, St. Paul, MN.

Impact Statements

Reliable DNA-based identification of Ditylenchus species provides plant regulatory officials with a definitive means of confirming or denying the presence of a nematode of international regulatory significance.
The recently-discovered and as yet undetermined Meloidogyne species found co-infesting agricultural land in southern NM should pose no economic threat to all commonly-grown summer annual crops or alfalfa, based on host assays completed in 2013.
Low-dose application of 1,3-D through buried drip can provide grape producers with a tool to dramatically suppress root-knot nematode populations in the rhizosphere surrounding established vines.
Organic chile pepper produces choosing biofumigant crops for fall establishment in fields known to be infested with M. incognita should consider avoiding mustard varieties in favor of broccoli to avoid increasing nematode pressure.
A variety of Pratylenchus species are found in the tropics. P. speijeri does not appear to be limited to Africa.
Spinosad, spirotetramat, and thiophanate-methyl have potential use as post-plant treatments for management of nematodes in high value crops.
Published the genome sequence of an entomopathogenic nematode that is widely used as a biological control agent against insect pests
Developed a research program under the auspices of the Scientific Council on Antarctic Research to identify how terrestrial organisms (including nematodes) adapt to environmental changes. Developed an international effort to coordinate research on the effects of climate change on Antarctic terrestrial ecosystems. Determined lifecycle of a nematode model organism for understanding environmental stress response.
The stage for a population-level analysis of the genetic relationships of M. chitwoodi isolates has been set. This research is significant because it can lead to improved M. chitwoodi management strategies and diagnostics. Improved M. chitwoodi resistance could save millions of dollars in production costs and improve environmental quality by reducing the use of pesticides.
Molecular techniques are identifying genes used in parasitic reaction by the Soybean Cyst Nematode. These will be useful in developing soybean varieties with resistance to this serious nematode pest.
A molecular diagnostic technique for the soybean cyst nematodes will increase the accuracy of detecting the presence and quantification of these pests in the soil.
Developing an integrated understanding of the relationships among cover and rotation crops, nematode community, and changes in soil conditions are critical to growers making accurate decisions.
Identifying the biotic and abiotic factors of nematode adaptation and parasitic variability, leading to understanding basic aspects of the biological interactions and developing location-specific and applied solutions.

Date of Annual Report: 02/11/2015

Report Information

Annual Meeting Dates: 11/13/2014 - 11/14/2014
Period the Report Covers: 10/01/2013 - 09/01/2014

Participants

Abebe, Eyualem (ebabebe@mail.ecsu.edu) – Elizabeth City State University;
Caswell-Chen, Edward (epcaswell@ucdavis.edu) – University of California, Davis;
Elling, Axel (elling@wsu.edu) – Washington State University;
Hafez, Saad (shafez@uidaho.edu) – Univeristy of Idaho;
Hyman, Bradley (bhyman@citrus.ucr.edu) – University of California, Riverside;
Ingham, Russell (inghamr@science.oregonstate.edu) – Oregon State University;
Lawrence, Gary (glawrence@entomology.msstate.edu) – Mississippi State University;
Lawrence, Kathy (lawrekk@auburn.edu) – Auburn University;
Melakeberhan, Haddish (melakebe@anr.msu.edu) – Michigan State University;
Mengistu, Tesfamariam (tmekete@ufl.edu) – University of Florida;
Powers, Thomas (tpowers1@unl.edu) – University of Nebraska;
Robbins, Robert (rrobbin@uark.edu) – University of Arkansas;
Roberts, Philip (philip.roberts@ucr.edu) – University of California, Riverside;
Sipes, Brent (sipes@hawaii.edu) – University of Hawaii;
Thomas, Stephen (stthomas@nmsu.edu) – New Mexico State University;

Brief Summary of Minutes

Agenda:
Thursday November 13:

6:30-8:00 a.m. – Hot breakfast served at Drury Inn

8:00 a.m. Van departs Drury Inn for Skeen Hall, Room N-128 at NMSU; (for those with rental cars, I have 2-day campus parking permits for you).

8:30 a.m. Welcome and introductions (W-3186 Acting Chair, Steve Thomas)

8:40 a.m. Welcome and instructions (W-3186 Host, Steve Thomas)

8:45 a.m. Welcome and Project overview: (Dr. David Thompson, Administrative Advisor; and Associate and Director, College of Agricultural, Consumer and Environmental Sciences)

9:00 a.m. Graduate student presentations (~20 minutes each)

Carol Land (Auburn)

Amber Smith (Auburn)

Justin Luangkhot (Auburn)

10:00 a.m. Break

10:30 a.m. ---continue graduate student presentations (~20 minutes each)

Ni Xiang (Auburn)

Shankar Pant (Mississippi State)

Jian Jiang (Mississippi State)

11:45 a.m. Walk to The Game for lunch

1:30 p.m. Report presentations – state representatives (~20 minutes each)

Kathy Lawrence -Alabama

Phil Roberts- California

Ed Caswell-Chen – California

Brent Sipes - Hawaii

3:00 p.m. Break

3:15 p.m. ---continue report presentations

Gary Lawrence - Mississippi

Haddish Melakeberhan - Michigan

Tom Powers - Nebraska

Steve Thomas – New Mexico

5:00 p.m. Instructions for dinner (Steve Thomas) - Return to the hotel

6:00 p.m. Meet in the lobby and drive to restaurant (chosen by group) for dinner

Friday November 15:

8:00 a.m. Van departs Drury Inn for Skeen Hall room N-128 at NMSU

8:15 a.m. Wrap up any remaining reports

Bob Robbins - Arkansas

9:00 a.m. Business Meetings (Steve Thomas Presiding):

Increasing membership

Joint proposals

Annual report preparations

Meeting site selections for 2016 and 2017

Election of Secretary

Other matters

10:00 Break; Adjourn (5 folks have MUST leave for El Paso Airport at this time!!)

10:15 Tours or other activities for remaining attendees

12:00 Lunch plans (to be determined)

Afternoon departures

Annual Meeting Minutes (recorded by Kathy Lawrence):

Overview:

The 2014 W-3186 multi state nematology research project meeting was convened on the New Mexico State University campus in Las Cruces, NM on Thursday November 13, 2013. This meeting was organized and hosted by Steve Thomas (NM).

Scientist in attendance and the state they represent:
Bob Robbins (AR), Phil Roberts (CA), Tom Powers (NE), Haddish Melakeberhan (M), Gary Lawrence (MS), Kathy Lawrence (AL), Brent Sipes (HI), Steve Thomas (NM) and Dave Thompson (Administrative Advisor for W-3186, NM). Graduate students in attendance included Caroline Land (AL), Amber Smith (AL), Justin Launghkot (AL), Ni Xiang (AL), Shankar Pant (MS), and Jian Jiang (MS).
Announcements:

1) Acting Chair, Steve Thomas (NM) called the meeting to order at 8:30 a.m

2) The members were then informed that Saad Hafez, (ID) and Russ Ingham (OR) would not attend due to recent illnesses.

3) Each member introduced themselves explaining their affiliations with their respective universities or USDA-ARS employment.

Welcome Remarks:

1) Dr. David Thompson, Associate Dean and Director of the Agricultural Experiment Station at New Mexico State University and the W-3186 administrator advisor, welcomed our group to New Mexico. He reported the western directors considered our project successful and he was glad to see students present. Phil Roberts asked how the experiment station works in NM and David outlined their agronomic centers, research scientist and staff, programs and effect on employment.

2) Jerry Sims, Department Head, Entomology, Plant Pathology, and Weed Science (EPPWS) welcomed us.

Reports presented by graduate students:

Caroline Land (AL)

Amber Smith (AL)

Justin Launghkot (AL)

Ni Xiang (AL)

Shankar Pant (MS)

Jian Jiang (MS)

State reports by members of W-3186:

Kathy Lawrence (AL- root knot and reniform management on cotton)

Phil Roberts (CA - root-knot on multiple vegetable crops)

Brent Sipes (HI- reniform on tropical plants and pineapple)

Gary Lawrence (MS-Seed treatments available on all crops)

Haddish Melakeberhan (MI – Sugar beet cyst and tropic nematode groups)

Tom Powers (NE – ring nematodes across the country bar codes)

Steve Thomas (NM – root knot on chile and weeds)

Meeting was adjourned for the day at 5:30 p.m. and would resume on Friday.

Friday November 14, 2014 – The meeting resumed at 8:30 a.m.

State reports continued.
Bob Robbins (AR- species of root-knot nematode currently present in AR)

Business Meeting:

1) The meeting was called to order at 9:00 November 14, 2014 by chair Steve Thomas. The minutes from the 2013 meeting were accepted as written.

2) The officers of the members were reviewed and Steve Thomas is serving as Acting Chair for this meeting. Kathy Lawrence is filling is as secretary for Ed Caswell-Chen.

3) The 2015 W-3186 meeting will be in Alabama Nov. 5 and 6, 2015. Meeting locations were discussed and the group voted to meet on the Auburn University campus. The W-8136 groups will meet in conjunction with the S-1046 group. Kathy Lawrence will serve as Chair since she is hosting the meeting. Ed Caswell-Chen will serve as Vice Chair. Brent Sipes volunteered for Secretary for the next year. Officers and location were approved by the members attending.

4) Ed Caswell Chen from the University of California-Davis sent an invitation for the W-3186 to meet at Davis in 2016. Kathy Lawrence moved to accept his invitation and it was seconded by Phil Roberts and approved by the group.

5) Membership was discussed. Steve Thomas handed out a list of members and those attending. Phil Roberts suggested we put a letter together to the USDA to state the value of the scientist attending our meeting. Steve will draft a letter and Dave Thomas will send it though the Western region.

6) Haddish Melakeberhan asked if we wanted to do anything at the SON meeting in July. Phil said we could meet over an idea of a new funding opportunity if anyone knows of one. Tom is meeting at a soil biodiversity meeting next week and will check out any funding opportunities there.

7) Phil Roberts lead a discussion of depository of nematode collections. SON may have a collections committee and Steve Thomas will check with the regularity committee. $2000 of a widely prevalent nematode list is coming from APHIS and may give some to help with the nematode collection.

8) With no further business, the meeting was adjourned at noon.

Accomplishments

Objective 1: Characterize genetic and biological variation in nematodes relevant to crop production and trade. Alabama: Rotylenchulus reniformis resistant LONREN-1×FM966 breeding lines developed at Auburn University have demonstrated that the nematode resistance is accompanied by severe stunting, limited growth, and low yields. The objectives of this study were to evaluate the effects of applying nematicides to selected LONREN breeding lines on R. reniformis nematode populations, plant stunting, and yield. Four resistant breeding lines from the LONREN-1×FM966 cross, one susceptible line from the LONREN-1×FM966 cross, as well as LONREN-1, BARBREN-713, and the susceptible cultivar DP393 were evaluated with and without nematicides in the presence of R. reniformis. In the greenhouse, nematicides increased plant height across all genotypes compared to no nematicide. Rotylenchulus reniformis populations were 50% lower in the resistant lines compared to the susceptible lines at 45 days after planting (DAP). In microplot and field trials, the phenotypic stunting of all genotypes was reduced by aldicarb with increases in plant heights at 30 and 75 DAP. Increases in yields were evident across all genotypes treated with aldicarb. In all three trial environments, BARBREN-713 outperformed the LONREN-derived lines as well as ‘DP393’ in seed cotton yields, while having significantly lower R. reniformis egg densities than the susceptible genotypes. The results of this study indicate that the BARBREN-713 source of resistance will replace the LONREN source of resistant in future R. reniformis resistance research and breeding. Arkansas: I am working with soybean researchers in Georgia and Missouri to identify resistant markers to reniform nematode in RIL’s developed from crossing Magellan and PI 404198B. In an effort to identify root-knot nematodes in Arkansas using molecular methodology over 100 samples of root-knot were sequenced and identified. Six species (Meloidogyne arenaria, M. hapla, M. haplanaria, M. incognita, M. marylandi, and M. partityla were identified, with M. haplanaria, M. marylandi, and M. partityla new records from Arkansas. The Southern root-knot nematode Meloidogyne incognita was identified from 51 samples from 30 counties with 25 from soybean; M. haplanaria from 13 samples from 4 counties; M. marylandi from 5 samples from 4 counties; M. hapla from 5 samples from 2 counties; M. arenaria from 2 samples from 2 counties and M. partityla from 1 sample from pecan groves in 5 counties. An undescribed species of Punctodera was identified from the same pecan grove as M. partityla. All Meloidogyne species were reproduced using the single egg mass method, placed on appropriate hosts, re-sequenced and identified, and reproduced in greenhouse cultures for future study. California, Riverside (Hyman): Strelkovimermis spiculatus is an obligate parasite of mosquito larvae that breeds in environments of permanent flooding or in habitats subjected to periods of desiccation. Differences in epizootic levels within these habitats likely are due to variation at the genetic level. We evaluated whether nucleotide sequence variation levels might provide a basis for the development of molecular markers that correlate with infectivity phenotypes characteristic of different populations Argentine S. spiculatus populations. Partial gene sequences from the nuclear 18S gene and the mitochondrial nd4 gene were analyzed. Nucleotide sequences revealed a modest number of substitutions the 18S and nd4 genes over a short sequence expanse. Our results indicated that an expanded sampling of both nuclear and mitochondrial genes, with a special reference to nuclear genes encoding host range infectivity phenotypes, may be useful in the development of biomarkers for studying the population dynamics of S. spiculatus, and for correlating isolates with phenotypic traits useful for durable biological control practices. Mitochondrial DNA (mtDNA) encodes respiratory complex subunits essential to almost all eukaryotes; hence respiratory competence requires faithful duplication of this molecule. However, the mechanism(s) of its synthesis remain hotly debated. Here we have developed Caenorhabditis elegans as a convenient animal model for the study of metazoan mtDNA synthesis. We demonstrate that C. elegans mtDNA replicates exclusively by a phage-like mechanism, in which multimeric molecules are synthesized from a circular template. In contrast to previous mammalian studies, we found that mtDNA synthesis in the C. elegans gonad produces branched-circular lariat structures with multimeric DNA tails; we were able to detect multimers up to four mtDNA genome unit lengths. Further, we did not detect elongation from a displacement-loop or analogue of 7S DNA, suggesting a clear difference from human mtDNA in regard to the site(s) of replication initiation. We also identified cruciform mtDNA species that are sensitive to cleavage by the resolvase RusA; we suggest these four-way junctions may have a role in concatemer-to-monomer resolution. Overall these results indicate that mtDNA synthesis in C. elegans does not conform to any previously documented metazoan mtDNA replication mechanism, but instead are strongly suggestive of rolling circle replication, as employed by bacteriophages. As several components of the metazoan mitochondrial DNA replisome are likely phage-derived, these findings raise the possibility that the rolling circle mtDNA replication mechanism may be ancestral among metazoans. California, Riverside (Roberts): Genetic analysis, molecular mapping, and marker development were accomplished to determine the basis of resistance to the root-knot nematode M. incognita and the interacting fungal pathogen Fusarium wilt, races 1 and 4 in cotton. QTL regions for resistance to both nematode and wilt infection on homoeologous chromosomes 11 and 21 were fine mapped using the published Gossypium raimondii D5 whole genome sequence as a resource to design additional markers in the resistance regions. A similar approach was made for a region of chromosome 17 which harbors a major QTL for resistance to Fusarium wilt race 4. Phenotyping and marker analysis of a set of 34 chromosome substitution lines for reaction to M. incognita and Fusarium wilt races 1 and 4 was completed. A set of 43 isolates of Meloidogyne incognita (25), M. hapla (11), M. javanica (7), and M. arenaria (2) stored as second-stage juveniles were removed from cryopreservation storage and cultured on tomato plants to develop inoculum for screening a panel of resistant carrot germplasm lines. Some isolates had been stored in liquid nitrogen for 21 years, and all isolates showed good viability open thawing. On the carrot panel containing several diverse sources of resistance, only minor variation for ability to gall carrot roots was found among M. incognita isolates. Resistance was strongest and most broadly effective against M. javanica and M. arenaria isolates. In contrast, high levels of variation in root-galling were found among the M. hapla isolate x resistant carrot combinations. Analysis of multiple isolates of species in the plant-parasitic nematode genus Scutellonema was completed. Results of morphological and molecular comparisons clarified species relationships and provided a framework for resolving diagnostic issues for this genus. Hawaii: A survey was conducted to collect Heterorhabditis and Steinernema spp. in Hawaiian soils. Documenting natural populations strengthens the case for the introduction and use EPN for biological control. Collects for Heterorhabditis populations focused in coastal areas and for Steinernema at inland sites. Heterorhabditis was baited with Galleria mellonella and Steinernema with Tenebrio molitor. Nearly a quarter of sites contained some type of entomopathogenic nematode based on morphological observation. ITS rDNA sequences confirmed Heterorhabditis indica, Heterorhabditis sp. and Heterorhabditoides. Most Steinernema isolates are small and morphologically in the S. carpocaspi group. Mississippi: A developmental genomics analysis of candidate soybean genes involved in the resistant reaction occurring between Heterodera glycines (soybean cyst nematode [SCN]) and Glycine max (soybean), involving Jian Jiang, Gary W. Lawrence, Vincent P. Klink is underway. Worldwide, soybean cyst nematode (SCN) infection of soybean crops results in annual production losses ranging from 7 to 10%. The multinucleated structure nematode feeding structure (syncytium) that forms during infection affords the unique opportunity to isolate cells undergoing the reaction and understand its accompanying gene expression program. Cells undergoing the incompatible reaction have been isolated and analyzed for gene expression occurring exclusively in the incompatible reaction. This identified list of approximately 1,700 genes served as a pool of candidate resistance genes to study using molecular techniques. Highly induced expression of these candidate genes in the susceptible genotype (G. max[Williams 82/PI 518671), in several cases, resulted in identification of genes whose expression suppressed SCN infection. This result demonstrated the efficacy of the approach. Currently, we are testing dozens of candidate resistance genes. Candidate resistance gene analysis in relation to the defense response occurring between the soybean cyst nematode (SCN) and soybean is being conducted by Shankar R. Pant, Gary W. Lawrence, and Vincent P. Klink. Soybean cyst nematode (SCN) infection of soybean crops results in annual production losses ranging from 7 to 10%, worldwide, annually. In experiments that identified candidate resistance genes that are expressed specifically in the multinucleated syncytium undergoing the process of defense, supporting experiments resulted in the identification of the involvement of a Syntaxin 31 homolog (Gm-SYP38) functioning in defense. Furthermore, we identified ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1) and NONEXPRESSOR OF PR1 (NPR1) that function in salicylic acid (SA) signaling as playing a role in defense. Additional experiments revealed the involvement of BOTRYTIS INDUCED KINASE 1 homolog (Gm-BIK1-6) and the hemicellulose-modifying, xyloglucan endotransglycosylase/hydrolase (XTH) functioning in defense. Currently, we are employing overexpression and RNA interference to better understand the basis of resistance. Nebraska: We have continued to work in three areas of DNA barcoding for nematode identification. The first area has been in the development of primers and PCR amplification conditions that increase the taxonomic range of molecular diagnostics. Currently separate primer sets are used for cyst (Heterodera), root-knot (Meloidogyne), and ring (Criconematidae) nematodes. We have modified existing primer sets and conditions to include amplification of false root-knot nematode (Nacobbus) and lesion nematode (Pratylenchus). The new primer sets are still being tested. The second area of DNA barcoding development is the analysis of multiple isolates of species for determination of within and between species discriminations. This is an extremely important component of DNA identification based on barcodes and one that has been underdeveloped in most existing assays. Geographic range and sampling density are the two components of scale that we are trying to optimize. We are testing two groups with an expanded sampling design, Pratylenchus as a representative of an endoparasitic nematode that may be easily spread by movement of root-stock and Criconematidae, as an ectoparasitic nematode that may not move as readily as endoparasities. For Pratylenchus we currently have over 1,500 specimens examined microscopically representing 11 U.S. states and three Canadian provinces. For Criconematidae we have representatives from over 40 states and three continents. These isolates are being used to test the metrics of within and between species/group genetic distance, the degree of overlap between the distance values and the genetic distance to the nearest-neighbor specimen in another group. The final area of investigation also concerns barcode analysis. Numerous algorithms are currently used for assignment of specimens to species or OTUs (operational taxonomic units). Some of the algorithms are based on genetic distance, others incorporate a tree-building step, and several recently developed approaches apply likelihood and coalescent analyses. These are being tested using our plant-parasitic nematode datasets. New Mexico: The project to improve capability for using molecular tools to differentiate Ditylenchus species of regulatory concern from each other and from benign soil-inhabiting species that began in 2013 was completed. DNA was extracted from an additional 450 specimens from plant (alfalfa, garlic, onion, Phlox sp., and potato) and soil samples obtained from ID, MI, NE, NM, OR, SC and WA, Canada, and the Republic of Georgia. High-quality ~1kb 18S rDNA sequences were generated using modified primer sets, as were sequences for ITS1 and ITS2, and compared among the new specimens and those previously reported in GenBank. Ditylenchus spp. recovered from plant material were found to be largely clonal, particularly within a location, compared to those recovered from soil, which provided greater DNA sequence variation. The 18S sequence was reliable for separating D. dipsaci from D. destructior and both species from non-pathogenic soil-inhabiting species. However, inclusion of the ITS sequence with the 18S region was necessary to reliably separate D. gigas from D. dipsaci. Oregon: Biological characterization of Globodera ellingtonae: On April 28, 2008, a field at the Oregon State University Powell Butte Farm that was planted to potato in 2007 was sampled and found to contain cysts of Globodera which were morphologically and molecularly distinct from golden potato cyst (G. rostochiensis), pale potato cyst (G. pallida), and tobacco cyst (G. tobaccum) nematodes. Subsequently, in August and September of 2008 cysts matching the characteristics of those found at Powell Butte were recovered from two grower potato fields in Idaho. These nematodes were later (2012) described as a new species, G. ellingtonae. Very little is known about the biological properties of this species and its potential pathogenicity to potato or other crop plants. Lab, greenhouse, and field studies have begun to help characterize the biology of G. ellingtonae. In an effort to relate G. ellingtonae to pathotypes of G. rostochiensis and G. pallida, several potato varieties used as differential lines to define Globodera pathotypes in Europe were inoculated with 2,500 eggs of G. ellingtonae. Plants were grown for three months and cysts and eggs were counted to determine if each line was susceptible or resistant. ‘Cycloon’ which is resistant to G. rostochiensis Ro1 and G. pallida Pa2 was susceptible to G. ellingtonae. ‘Avondale’, ‘Banba’, ‘Galactica’, ‘Missaukee’ and ‘Slaney’ which are resistant to G. rostochiensis Ro1 but susceptible to G. pallida were resistant to G. ellingtonae. The differential line 65.346/129, resistant to all pathotypes of G. rostochiensis and susceptible to all pathotypes of G. pallida, was susceptible to G. ellingtonae. P55/7, resistant to G. pallida Pa1 was susceptible to G. ellingtonae, and V-15-71, resistant to G. rostochiensis Ro1 and Ro2 was susceptible to G. ellingtonae. Therefore, the reaction of several potato lines to G. ellingtonae often differed from that of pathotypes of G. rostochiensis or G. pallida suggesting that the pathotype is unique. This further supports the elevation of G. ellingtonae as a new species. During 2012, holes 6 inches deep and 6 inches in diameter were augured in field plots, filled with soil infested with 0, 5, 10, 20, or 40 eggs/g of G. ellingtonae, (n=7) and planted to ‘Russet Burbank’ potato on May 17. At harvest (September 13) average egg densities were 5, 43, 62, 92, and 114 eggs/g in the 0, 5, 10, 20, or 40 eggs/g inoculum levels, respectively, but there were no differences in tuber weight between the different inoculum levels. During 2013, holes 6 inches deep and 12 inches in diameter were augured in field plots, filled with soil infested with 0, 5, 10, 20, 40, or 80 eggs/g of G. ellingtonae, (n=5) and planted to potato ‘Desiree’ or ‘Russet Burbank’ on May 27. At harvest (September 23) average egg densities in the ‘Desiree’ plots were 1, 148, 222, 209, 317, and 267 eggs/g; and in the ‘Burbank’ plots were 2, 121, 151, 343, 261, and 127 eggs/g in the 0, 5, 10, 20, 40 or 80 eggs/g inoculum levels, respectively. There were no significant differences in ‘Desiree’ top growth or tuber weight between different egg densities. Top growth of ‘Russet Burbank’ appeared less in the 80 egg/g treatment but the difference was not significant. There were no differences of any of the individual tuber size classes or in total tuber weight between the different inoculum levels. Although total tuber weight in the 80 egg/g treatment was 51% that in the non-inoculated plots, this difference was not significant (P<0.05). Total yield in this trial may have been reduced from damage due to a hailstorm on August 16. Objective 2: Determine nematode adaptation processes to hosts, agro-ecosystems and environments. California, Davis: Dispersal is a key step for movement of plant pathogens and for the development of disease. Plant pathogens such as fungi and plant-parasitic nematodes disperse by water, wind, soil, contaminated field equipment, plant stock, humans, and insects. The brown garden snail, Helix aspersa, is a pest found in many agricultural settings. Snails feed by grazing on substrates they pass over, and in the process they consume an array of microbes including plant pathogens and may move them to new locations. To determine whether viable pathogen propagules can transit the snail digestive tract, we tested two fungal pathogens, Fusarium circinatum and Rhizoctonia solani and three plant-parasitic nematodes, Meloidoygne hapla, Ditylenchus dipsaci, and Aphelenchoides ritzemabosi. We fed snails fungal mycelium on filter paper. Ninety percent of tested snails defecated viable fungal propagules for up to 9 days. The plant-parasitic nematodes were fed to snails on an infested carrot disc. Active nematodes were recovered from feces starting at 24 hours and continuing up to 8 days. These experiments demonstrate for the first time that viable plant-parasitic nematodes can transit the digestive tract of brown garden snails. We also determined that second-stage juveniles (J2s) of the root-knot nematode species Meloidogyne hapla and M. incognita after consumption by H. aspersa can emerge from snail fecal pellets to successfully infect and reproduce on tomato (Lycopersicon esculentum) host plants. Individual carrot discs (1.75 g) were infested with an aqueous suspension of 1000 J2s of the two nematode species. The fecal pellets from snails fed a single infested carrot disc were collected on each of 5 days subsequent to snail feeding, and placed at the base of tomato seedlings held in growth chambers. After 2 months the tomato plants showed infection with galled roots, egg masses, and substantial reproduction with the ratio of final J2s from roots to initial J2s fed to snails (i.e., Pf/Pi) of 3.5 and 9.1 for M. hapla and M. incognita respectively. Tomato shoot weights were significantly reduced by infection with both M. hapla and M. incognita. Helix aspersa ingested root-knot nematode J2s and those J2s survived ingestion and passage over the snail radula, transit through the alimentary canal, deposition in fecal pellets, emergence from pellets, movement into the soil, and then successfully locating and infecting host roots. The control measures for root-knot nematodes may need to include a greater emphasis in controlling snails as possible vectors of disease. The passive, phoretic dispersal of plant-parasitic nematodes through endozoochory in H. aspersa may represent a significant, unrecognized means of nematode invasion and colonization within and among agricultural fields and other environments. Brown garden snails are capable of moving faster and further than plant-parasitic nematodes, which suggests that snails may be an important element in plant-parasitic nematode dispersal, dissemination, and disease transmission. California, Riverside (Hyman): Two improved bioassays were developed to establish infectivity baselines for selection experiments using mermithid nematode variants. Comparative infectivity of Romanomermis iyengari, Romanomermis culicivorax and Strelkovimermis spiculatus using larvae of three mosquito spp. Aedes sierrensis, Aedes aegypti and Culex pipiens were evaluated with “plate” and “tray” bioassays at selected intensity of infections. Using the “plate” bioassay, single mosquito larvae were immersed in 5 ml of water within individual depressions of 12-well, polystyrene tissue culture plates. One, three, or five preparasitic juveniles (J2) were added to each well. In the “tray” bioassay, polyethylene trays containing 500 ml water and 100 mosquito larvae were exposed to 500 (5:1, nematode:insect host) or 1,000 (10:1) J2s. Percentage infection (PINF, infectivity) and intensity of infection (IINF, # nematodes per infected larvae) number were determined only after emergence of post-parasitic J3 juveniles. Under the bioassay conditions, all three species of nematodes resulted in infections in all mosquito hosts, but R. iyengari exhibited better effectiveness in the parasitism of mosquito larvae. The three species of mosquitoes presented high levels of susceptibility to each of the three species of nematodes, but in general C. pipiens and A. sierrensis were slightly more susceptible than A. aegyti. The “plate” bioassay was more efficient in measurement of infectivity of the mermithid species and in establishing baseline characteristics for these mosquito-parasitic nematodes. The "tray" bioassay was an effective bioassay for large cohorts of both infective juveniles and host larvae and, potential for field interactions. Idaho: The interaction of Verticillium dahliae and lesion nematodes showed an additive effect on mint hay yield in the greenhouse experiment carried out in 2013. Verticillium dahliae alone caused 44 % damage in mint hay yield. Root lesion nematode Pratylenchus neglectus was also pathogenic to mint. A 23 and 46 % reduction on mint hay were caused by P. neglectus alone or in combination with V. dahliae, respectively. P. penetrans alone caused 44 % yield reduction of mint hay while combination of P. penetrans and V. dahliae killed almost all plants (98%). Population of P. penetrans is increased by 41 fold which indicates that mint is an excellent host for P. penetrans. The experiment was repeated this year to confirm the first years’ data. Mint are already cut for fourth time and harvested. The data from repeated experiment confirmed the first years’ result. The survey carried out in mint growing areas in Nampa, Wilder, Caldwell, Marsing, Fruitland, Nyssa, Emmett, and Ontario in 2011, 2012, 2013 and 2014 showed root lesion nematode in 155 samples, root-knot nematode in 48 samples, spiral nematode in 108 samples, and pin nematode in 142 samples, sheath nematode was found in 3 samples, dagger nematode in 5, ring nematode in 7, and stubby root nematode in 12 samples. County wise, 149 samples were surveyed in Canyon, 12 in Malheur, and two in Gem. In total, 163 samples have been analyzed until now. Nematode were recorded in the range of 10-2750 for root lesion nematode, 10-6900 for root knot nematode, 10-6550 for spiral nematode, and 30-67200 for pin nematode per 500 cc soil sample. Michigan: Developing management practices that reduce the impact of sugar beet cyst nematode (SBCN) and understanding soil biology and food web structure to improve soil health are two of the critical research priorities for the Michigan Sugar Beet Industry (MSBI). In order to develop integrated SBCN and soil health management, the relationships among the rotation crops, SBCN, other PPN, beneficial nematodes, soil health, and soil types need to be understood. Using sugar beet varieties (EL53, EL57, EL59, EL61 and EL64) from the USDA laboratory at MSU, we investigated how these varieties affect all nematodes in different soil types and soil health in 2012 and 2013. Soybean and corn are added as controls for production systems. Soil samples were collected every 4-6 weeks during the growing season and nematodes extracted and identified to herbivore (cyst and other PPN), bacteriovore, fungivore, predator and omnivore trophic groups. Trophic group data were processed to extract bio-ecological, nutrient cycling potential, and soil food web structure. Preliminary analyses of pre-plant and harvest data showed 24 and 8 cysts/100 cc of soil and 17 and 19 herbivore genera present in 2012 and 2013, respectively, suggesting potential problems than the target nematode, SBCN. While the levels of cysts were higher in 2012 than in 2013, statistically low numbers of cysts in 2013 were recovered in three sugar beet varieties (EL53, EL57 and EL59) and corn. Significant low population density of both cyst and root-lesion nematode were observed in the plots with EL59 variety. Soil food web structure, as described by nematode community analysis, varied within crops, suggesting different crops have different impact on soil health however high enrichment levels were observed in the plots grown with soybean and corn. A combination of cyst and other PPN population dynamics, and soil food web data support the hypothesis that there are distinct interactions among the crops, SBCN and soil conditions. New Mexico: Dr. Jonathan Eisenback is finalizing morphological description of the new species of Meloidogyne that was recovered from purple nutsedges in two field locations in Dona Ana County, NM in 2012. In collaboration with Dr. Stephen Hanson (EPPWS Department, NMSU), ribosomal DNA 18S, ITS1, and ITS2 and mitochondrial COII gene segments for this nematode have been sequenced. Studies conducted in 2013 were repeated in 2014 to determine the host suitability of major crops produced in southern NM to this nematode. Cotton, chile pepper, corn, tomato, and onion failed to host the new nematode in both studies. Low to moderate nematode reproduction occurred on one or more of the sorghum, winter rye, or alfalfa plants tested during the second study, whereas no reproduction was observed in the 2013 study. Wheat, bentgrass, and perennial ryegrass showed variability in response in both tests, with some plant within each species being non-host, while others ranged from poor hosts (0 < RF < 1) to hosts (1 < RF < 10). Yellow nutsedge (Cyperus esculentus) and purple nutsedge (C. rotundus) were the best hosts for this nematode, resulting in average population increases of over 26-fold on yellow nutsedge and over 5-fold on purple nutsedge after 45 days. A study established in late 2013 to determine the effect of previous crops on subsequent M. incognita reproduction on yellow and purple nutsedges was harvested and repetition of the study begun in 2014. These studies are necessary to accurately predict how different cropping scenarios will impact root-knot nematode carryover to future crops from perennial weeds. Both nutsedges were inoculated with eggs recovered from cotton, chile, or corn (the major summer annual crops in southern NM). Inoculum from tomato was also included to allow extrapolation to results from previous studies. The experiments are harvested upon accumulation of 750 heat units (DD24 = one life cycle for the nematode), and eggs extracted from roots. Data will be used to calculate the crop-specific M. incognita carryover potentials for both nutsedge species for use in developing IPM management recommendations for the nutsedge/nematode pest complex. Oregon: Globodera spp. eggs go through a diapause which remains dormant until favorable hatching conditions are reached. Because of the regulatory concerns with cyst nematodes, it is often only possible to rear eggs for research in the greenhouse. However, hatch is often lower for greenhouse-produced eggs than for eggs obtained from the field. The goal of this research was to determine storage conditions for G. ellingtonae eggs produced in the greenhouse that would increase percentage hatch. Over three years, G. ellingtonae greenhouse-produced eggs were stored in different environments (-20°C, 4°C, room temperature, and the field) in either dry or moist soil. Percentage hatch after exposure to the different environments was determined in potato root diffusate. Across two experiments, field-produced eggs had higher hatch rates (65.2%) than greenhouse-produced eggs (10.4%). Temperature did not have an appreciable influence on hatch of eggs stored dry in two experiments (2.8 to 8.4% and 3.8 to 8.6%), but hatch of eggs stored in moist soil was significantly higher than in dry soil at all temperatures except -20°C (26.8% and 28.7%). However, the ability of G. ellingtonae greenhouse-, microplot-, and field-produced eggs to reproduce on potato in field microplots was not different. While it may not be possible to produce G. ellingtonae eggs in the greenhouse that have the magnitude of hatch as those produced in the field, hatching can be greatly increased by storing eggs in moist soil at either 4°C or room temperature. Objective 3: Develop and assess nematode management strategies in agricultural production systems. Arkansas: Annually I test all new soybean entries submitted to the Arkansas Soybean Variety Testing Trials for reniform nematode reproduction. In 2014 this was 184 entries. A single plant of each variety was grown in each of 5 separate 4 inch diameter clay pots. As a germinated seedling was transplanted into each pot it was inoculated with 2,000 vermiform reniform nematodes. Three resistant varieties (Forrest, Hartwig and Anand) used as resistant checks while Braxton was used as a susceptible check and one pot in each rep was inoculated and left fallow as a check on reniform survival. The test was terminated after 12 weeks. Of the 184 entries there were 13 (Armor AX4520, Armor AX4450, Asgrow AG5535 GENRR2Y, Delta Grow DG4940RR, Delta Grow DG5230GENRR2Y, Dyna-Gro S52RY75, Eagle Seed ES5335RY, LG Seeds C5252R2, MPG 5214NRR, Mycogen X54522NR2, S11-20356, S11-20124, Willcross WX 2524N) that did not differ in reproduction than the resistant varieties Hartwig and Anand) and have probable rotation usefulness. Similar tests were also done for 179 varieties and breeding lines submitted by Southern Public Soybean Breeders from Arkansas, Illinois (Southern Illinois), Missouri, South Carolina (Clemson) and the USDA (Jackson, TN). Of the 179 entries, 31 were as resistant as the resistant varieties Anand and Hartwig. The specifics including statistical analysis will be reported at the Beltwide Cotton Conferences in San Antonio in January 2015. A rotation using two new varieties of resistant soybean (one moderately and the other highly resistant and a susceptible (9 treatments)) was initiated in a field with a high population of race 5 SCN in 2012. In 2012 the at plant egg count per 100 CC soil averaged 4022 overall and at harvest averaged 2480 in the highly resistant (HR) line, 6233 in the moderately resistant (MR) and 9793 (S) in the susceptible line. The yield was 35.83 BU/A for the HR, 32.90 for the MR, and 28.97 for the S. In 2013 the eggs counts were not different at plant or harvest, the treatment yields following the HR averaged 39.6, MR 36.4, and S 32.5 BU/A. In 2014 the eggs counts were not different at plant or harvest, the treatment yields following the HR averaged 36.8, MR 34.3, and S 33.7 BU/A. At $15 / BU using the moderately resistant would have gained $58.5 / acre while the highly resistant would have gained $102 in 2012. In 2013 the rotations yielded equal whereas the HR /HR yielded 39 B/A, the MR/MR = 39.6 B/A and the S/S = 32.3 B/A with the resistant increase over $100 or more. In 2014 the HR /HR yielded 39B/A, the MR/MR = 36 B/A and the S/S = 33.8 B/A with the resistant increase over $33 or more California, Riverside (Roberts): In cowpea (Vigna unguiculata), a high density map containing more than 1100 EST-derived SNP markers and a high-throughput SNP genotyping platform based on the KASP technology were used to refine the genomic locations of QTLs determining resistance to root-knot nematodes and Fusarium wilt in cowpea inbred populations. Multiple screens with M. incognita and M. javanica isolates were used to develop advanced blackeye cowpea breeding lines with dual resistance to both nematodes. Replicated field trials in Tustin, CA and Parlier, CA on infested field plots showed significantly higher grain yields of lines carrying multiple resistance genes, compared to lines with a single resistance gene or no resistance genes, confirming the protective value of the stacked resistance genes. Hawaii: Radopholus similis is an endoparasitic migratory nematode that causes anthurium decline. Our objective was to evaluate the efficacy of spinosad, spirotetramat, and thiophanate-methyl for the control of R. similis in anthurium. Plants were weighed, transplanted into 15-cm-d clay pots filled with cinders and inoculated with 3000 R. similis. Six months later, treatments of 4.8 mg spinosad, 4.8 mg spirotetramat, 0.01 g thiophanate-methyl, or nothing were applied to the leaves in 50 ml water. Two months later, leaf number and leaf area of the youngest mature leaf were recorded. The average number of leaves on uninoculated plants treated with spinosad, spirotetramat, thiophanate-methyl, or water was 9, 10, 9, and 10, respectively. The average number of leaves on inoculated plants treated with spinosad, spirotetramat, thiophanate-metyl, or water was 11, 9, 11, and 9, respectively. The average leaf area for uninoculated plants treated with spinosad, spirotetramat, thiophanate-methyl, or water was 90.6, 101.2, 96.9, and 77.5 cm2, respectively, On inoculated plants treated with spinosad, spirotetramat, thiophanate-methyl, or water leaf area was 91.7, 84.5, 76.2, and 92.5 cm2, respectively. Anthurium treated with spinosad, thiophanate-methyl, spirotetramat, or water increased weight 17, 16, 17, and 14 fold whereas those inoculated with nematodes increased 16, 14, 14, and 15 fold, respectively. Spinosad controls anthurium decline and maybe a treatment option for growers. Reniform nematode, Rotylenchulus reniformis is an economically important plant-parasitic nematode of pineapple. This pathogen can reduce pineapple marketable yield by 26.8-50%. Lack of host resistance in pineapple raises a need for nematode management. Spirotetramat is a group 23 insecticide, a lipid biosynthesis inhibitor with ambimobile translocation. Lipids play a significant physiological role in embryogenesis and molting of plant-parasitic nematodes therefore inhibition of lipid biosynthesis may provide a critical management tool. The objective of this study was to determine if spirotetramat is active against reniform nematode. Greenhouse bioassays were conducted where pineapple crowns were planted in steam-sterilized soil in 20-cm-d biodegradable pots. Approximately 3,000 R. reniformis eggs were inoculated onto 4-month-old plants. Four levels (0, 88, 100 and 175 g a.i/ha) of spirotetramat were applied 1 month post inoculation. Plants were harvested 6 months later for shoot and root weights, and a 250 cm3 soil sample collected. Data were normalized by log10 transformation and subjected to analysis of variance. The maximum proportion of nematode reduction was 64 % at 88 g a.i. spirotetramat/ha rate with a corresponding reduction in dry root weight of 14.4% and an increase in shoot weight of 1.4% compared to the water treatment control. The 88 g a.i. spirotetramant/ha rate gave promising reductions in nematode numbers while promoting plant growth. Idaho: Microplot study to evaluate of new nematicides (Movento and Velum) on pin nematode including few lesion and root-knot nematodes has been done. Mint were transplanted in the microplot buckets and chemical applied at planting and post plant. Each bucket was divided into two compartments, one compartment was harvested this year and another will be continued for next year. This year data showed significant decline on pin nematode population in all treatments as compared to untreated control. The effect of non-ionic wetting agents (soil surfactant) on movement of Mocap has been evaluated in the greenhouse. The experiment was repeated to confirm the first experiment’s results under greenhouse condition. Data showed no significant effect of the products on the Mocap movement. Michigan: Use of crop rotation, cover crops, reduced tillage and soil health soil health (organic matter, biological, physiochemical, nutritional and water holding properties) are cross-cutting priorities for many Michigan agricultural communities. While providing agronomic benefits, most cover and rotation crops are hosts to many plant-parasitic nematodes (PPN) that can cause economic loss. Moreover, all of the crops and tillage practices impact soil biology and soil health in many ways. Understanding how the agronomic practices impact soil biology and soil nutrient cycling is critical to soil health management across cropping systems. The long-term goal is to develop soil health management strategies that apply across cropping systems. We have initiated comparison of nematode community analysis and soil food web structures in different cropping systems. More specifically, how trophic group and colonizer-persister levels of beneficial nematodes relate to one another as well as with those of herbivores. The systems being studied include corn-soybean rotation under different till no-till to manage soybean cyst nematode, use of cover crops in sugar beet production system in different soil types, and carrot production. On-going are analyses to determine the relationship between soil food web function and structure in the different systems. Mississippi: Emergence of new nematicidal products. Several agricultural chemical companies are in the process of developing products designed for nematode control in row and vegetable crops (Table 1). Efficacy studies have been conducted with these products to determine their effect on nematode infestations of field crops. Table 1. Experimental and Existing Nematicidal Product by Company, Product and Application Method Company Product Application ADAMA MCW-2 – NIMITZ (fluensulfone) In-furrow spray AMVAC Counter 20G (Terbufos) In-furrow granular Thimet (Phorate) In-furrow granular Bayer Velum Total (Fluopyram + Imidacloprid) In-furrow spray Aeris seed applied system (Thiodicarb) Seed treatment Votivo (Bacillis firmis) Seed treatment DuPont Vydate L (Oxamyl) In-furrow spray Vydate C-LV (Oxamyl) Foliar spray Q8U80 In-furrow spray Monsanto Numbers (1-14) Seed treatment Marrone MBI- 38 In-furrow spray NuFarm Azadirachtin, Nematox, Senator Seed treatment Neem Oil, albendazole, Imidacloprid Syngenta Avicta Complete (abamectin) Seed treatment New Mexico: Studies were conducted on a golf course at the University of New Mexico to determine if severe damage to bentgrass greens resulting from high populations of Mesocriconema spp., Pratylenchus spp., and Longidorus breviannulatus could be successfully managed using current labeled rates of Avid® (2% abamectin). Maximum application of the product in 2013 reduced populations of Mesocrionema and L. breviannulatus below damage thresholds, but resurgence of Mesocriconema was observed in March 2014. Subsequent maximum application of Avid again reduced populations below the damage threshold by June, and populations remained below threshold in October. Pratylenchus populations were not managed well in these studies. However, damage symptoms on greens were no longer evident by June 2014, and usage was resumed.

Publications

Bailey, D. L., K. S. Lawrence, and D. W. Held. 2014. Soybean variety soil type and irrigation effects on reniform nematode populations. Proceedings of the 2014 Beltwide Cotton Conference Vol. 1: 270-275. National Cotton Council of America, Memphis, TN. http://www.cotton.org/beltwide/proceedings Bailey D. L., K.S. Lawrence, C. J. Land, R. B. Sikkens, C.H. Burmester and C. Norris. 2014. Cotton Variety and Fungicide Combinations for Seedling Disease Management in North Alabama, 2013. Report 8:ST018 DOI:11.1094/PDMR08. The American Phytopathological Society, St. Paul, MN. Bailey D. L., K.S. Lawrence, R. B. Sikkens, C. J. Land and C. Norris. 2014. Evaluations for Cotton Disease with the Use of Fungicide Management in North Alabama, 2013. Report 8:ST019 DOI:11.1094/PDMR08. The American Phytopathological Society, St. Paul, MN. Cabos, R.Y.M., B.S. Sipes, C. Nagai, M. Serracin, and D.P. Schmitt. 2012. Host plant resistance for nematode control in coffee. 51st Annual Meeting of the Society of Nematologists. Savannah, GA. Cabos, R.Y.M., K.H. Wang, B.S. Sipes, W.P. Heller, T.K. Matsumoto. 2013. Detection of plant-parasitic nematode DNA in the gut of predatory and omnivorous nematodes. Nematropica. 43:44-48. Chen, P., J.C. Rupe, D.G. Dombek, T. Kirkpatrick, R.T. Robbins, C. Wu, and P. Manjarrez. 2013. Registration of ‘UA 5213C’ Soybean. Journal of Plant Registrations. Cordero, Marco A. and Robert T. Robbins. 2013. Taxonomic identification of species of criconematidae from the permanent slide collection of R. T. Robbins. Society of Nematology Knoxville Meetings Program. Pg. 40. Donald, P., K. Lawrence, T. Kirkpatrick, B. Kemerait, J. Bond, D. Herschman, C. Overstreet, A. Wrather, G. Lawrence, S. Koenning, P. Agudelo and C. Canaday. 2014. Occurrence, distribution, and impact of nematodes in soybean fields in the southern United States. Journal of Nematology Vol. 46:154-155. Frazier, M.J., N. Olsen, and R.E. Ingham. 2013. The Feasibility of Irradiating Raw Potatoes for Sprout Control and Destruction of Columbia Root-knot Nematode. American Journal of Potato Research. 90:131. Habteweld, A., D. Brainard, M. Ngouajio, S. Kravchenko, and H. Melakeberhan. 2014. Potential use of compost for managing nematodes, soil health and carrot yield. 6th International Congress of Nematology, Cape Town, South Africa. Journal of Nematology 46: 171. Hafez, Saad L., and Mahesh P. Pudasaini (2014). Interaction of lesion nematodes and fungus (Verticillium dahliae) in mint. Paper presented at 6th International Congress of Nematology, 4 to 9 May, 2014, Cape Town, South Africa, (Abstract). Hafez, Saad L., and Mahesh P. Pudasaini, 2015. Efficacy of Movento alone or in combinations with other compounds in drip irrigation system for the management of onion nematodes, 2013. Plant Disease management report, Vol. 9 (Submitted) Hafez, Saad L., and Mahesh P. Pudasaini, 2015. Effect of Movento alone or in combinations with Vydate or Vapam for control of Columbia root-knot nematode in Potato, 2012. Plant Disease management report, Vol. 9 (Submitted) Hafez, Saad L., and Mahesh P. Pudasaini, 2015. Optimum timing of Movento application for control of Columbia root-knot nematode in Potato, 2010. Plant Disease management report, Vol. 9 (Submitted). Huynh BL, Ehlers, JD, Close TJ, Cissé N, Drabo I, Boukar O, Lucas MR, Wanamaker S, Pottorff M, Roberts PA. 2013. Enabling tools for modern breeding of cowpea for biotic stress resistance. Pp. 183-200 in Translational Genomics for Crop Breeding, Vol. I: Biotic Stress. Varshney R, Tuberosa R, eds. Wiley-Blackwell, USA. 368 pp. Ingham, R.E., P.B. Hamm and B.A. Charlton. 2013. Nematicide application strategies to control nematodes in potato. Journal of Nematology 45:267 Ingham, R.E.,. I.A. Zasada, D.A. Navarre, D.R. Kroese, A.B. Peetz, M. Ballato, and N.M. Wade. 2012. Hatching and reproduction of a new species of Globodera (G. ellingtonae) found near Powell Butte, Oregon. Journal of Nematology 44:469-470. Kandouh, B. and B. Sipes. 2014. Differences among red-skinned potato cultivars and their response to Meloidogyne species. Nematropica 44:47-50. Khanal, Churamani and R. T. Robbins. 2013. Expanded host range of Heterodera urticae from Arkansas. Society of Nematology Knoxville Meetings Program. Pg. 39-40. Khanal, Churamani and R. T. Robbins. 2014. Meloidogyne partityla, a new root-knot species to Arkansas, Phytopathology 104(Suppl. 2):S2.6 Dallas TX Feb 2-3, 2014. Khanal, Churamani and R. T. Robbins, 2014 Meloidogyne partityla, a new Root-Knot species to Arkansas. Southern American Phytopathological Society meeting, Dallas. Khanal, Churamani, Weimin Ye and R. T. Robbins 2014. A new record of Meloidogyne partityla and an unknown species of Punctodera from Arkansas. American Phytopathological Society annual meeting, Minneapolis. Land, Caroline, K. S. Lawrence. 2014. Greenhouse Evaluation of Inoculation Methods and Commercial Cotton Cultivars in the Presence of Verticillium Wilt. (In Press) The American Phytopathological Society, St. Paul, MN. Land, C.J., K. S. Lawrence, C. H. Burmester, and C. Norris. 2014. Evaluation of experimental nematicides for the management of the reniform nematode in north Alabama, 2013. Report 8:ST015 DOI:11.1094/PDMR08. The American Phytopathological Society, St. Paul, MN. Land, C.J., K. S. Lawrence, C. H. Burmester, and C. Norris. 2014. Experimental biological management of the reniform nematode in north Alabama, 2013. Report 8: ST016 DOI:11.1094/PDMR08. The American Phytopathological Society, St. Paul, MN. Land, C.J., K. S. Lawrence, S. Nightengale. 2014. Efficacy of experimental biological management of the root knot nematode in Alabama, 2013 Report 8: ST017 DOI:11.1094/PDMR08. The American Phytopathological Society, St. Paul, MN. Land, C.J., K. S. Lawrence, C. H. Burmester, and C. Norris. 2014. Experimental Nematicides for management of the reniform nematode in North Alabama, 2013. Report 8:ST014 DOI:11.1094/PDMR08. The American Phytopathological Society, St. Paul, MN. Land, C. J., K. S. Lawrence, B. Meyer, C. H. Burmester. Verticillium Wilt on-farm cotton cultivar variety evaluations. 2014. Proceedings of the Beltwide Cotton Conference, Vol. 1: 266-269. National Cotton Council of America, Memphis, TN. http://www.cotton.org/beltwide/proceedings/2005-2012/index.html Lawrence, K.S., C. Land and R. Sikkens. 2014. A new in-furrow nematicide for Rotylenchulus reniformis and Meloidogyne incognita nematode management in cotton. Journal of Nematology Vol. 46:191-192. Lawrence K. S., C. J. Land, R. B. Sikkens, C.H. Burmester and C. Norris. 2014. Cotton Variety and Nematicide Combinations for Reniform Management in North Alabama, 2014. Report 8:ST001 DOI:11.1094/PDMR08. The American Phytopathological Society, St. Paul, MN. Lawrence K. S., C. J. Land, R. B. Sikkens, C.H. Burmester and C. Norris. 2014. Cotton Variety and Nematicide Combinations for Reniform Management in North Alabama, 2014. Report 8:N001 DOI:11.1094/PDMR08. The American Phytopathological Society, St. Paul, MN. Lawrence, K., G. Lawrence, T. Faske, C. Overstreet, T. Wheeler, H. Young, S. Koenning, J. Muller, R. Kemerait, H. Mehl. 2014. Cotton variety and nematicide combinations for reniform and root-knot management across the cotton belt. Proceedings of the 2014 Beltwide Cotton ConferenceVol. 1: 295-301. National Cotton Council of America, Memphis, TN. http://www.cotton.org/beltwide/proceedings Lawrence, K. S., C. D. Monks, and D. Delaney. Eds. 2013 AU Crops: Cotton Research Report. March 2014. Alabama Agricultural Experiment Station Research Report Series No. 43. file:///F:/2011%20Passport/AU%20Crops%20report/AU%20Crops%20cotton%20%20report%202014/Cotton%20Bulletin%202014.pdf. Lawrence, K., M. Olsen, T. Faske, R. Hutmacher, J. Muller, J. Mario, R. Kemerait, C. Overstreet, G. Sciumbato, G. Lawrence, S. Atwell, S. Thomas, S. Koenning, R. Boman, H. Young, J. Woodward, and H. Mehl. 2014. Cotton disease loss estimate committee report, 2013. Proceedings of the 2014 Beltwide Cotton Conference Vol. 1: 247-248. National Cotton Council of America, Memphis, TN. http://www.cotton.org/beltwide/proceedings Lawrence K. S., R. B. Sikkens, C. J. Land and C. Norris. 2014. Fungicide Combination Evaluations for Cotton Seedling Disease Management in North Alabama, 2013. Report 8:ST0002 DOI:11.1094/PDMR08. The American Phytopathological Society, St. Paul, MN. Lee, H.K., G. W. Lawrence, J. L. DuBien and K. S. Lawrence. 2014. Seasonal variation and cotton-corn rotation in the spatial distribution of Rotylenchulus reniformis in Mississippi cotton soils. Nematropica 44:(In Press). Lewis, S.C., P. Joers, S. Wilcox, J. D. Griffith, H. T. Jacobs, and B. C. Hyman. 2015. A rolling circle replication mechanism produces multimeric lariats of mitochondrial DNA in Caernorhabditis elegans. PLoS Genetics, in press. Li, Ruijuan, Aaron M. Rashotte, Narendra K. Singh, David B. Weaver, Kathy S. Lawrence, Robert D. Locy. 2014. Integrated signaling networks in plant responses to sedentary endoparasitic nematodes – a perspective. Plant Cell Report (doi:10.1007/s00299-014-1676-6). Li, Y, Lawrence GW, Lu S, Balbalian C, Klink VP (2014) Quantitative Field Testing Heterodera glycines from Metagenomic DNA Samples Isolated Directly from Soil under Agronomic Production. PLoS ONE 9(2): e89887. doi:10.1371/journal.pone.0089887 Luangkhot, J., K.S. Lawrence, and J. Spiers. 2014. Actinidia sp. susceptibility to Phytophthora. 2014 APS-CPS Joint Meeting. (In Press) The American Phytopathological Society, St. Paul, MN. Melakeberhan, H. and Wang, W. (2013). Proof-of-concept for managing Meloidogyne hapla parasitic variability in carrot production soils. Nematology, 15: 339-346. Melakeberhan, H., Schmidt. T., Maung, Z.T.A. Teal, T., Yildiz, S., Kimenju, J.W., Kwoseh, C. and Saka, V. 2014. Quantifying biological basis of soil health degradation in selected sub-Saharan Africa soil groups. 6th International Congress of Nematology, May 9, Cape Town, South Africa. Journal of Nematology 46: 205. Pant, S.R., P.D. Matsye, B.T. McNeece, K. Sharma, A. Krishnavajhala, G.W. Lawrence, V.P. Klink. 2014. Syntaxin 31 function in Glycines max resistance to the plant-parasitic nematode Heterodera glycines. Journal of Nematology Vol. 46: 216. Pant, Shankar R., Prachi D, Matsye, Brant T. McNeece, Keshav Sharma, Aparna Krishnavajhala, Gary W. Lawrence and Vincent P. Klink. 2014. Syntaxin 31 function in Glycines max resistance to the plant-parasitic nematode Heterodera glycines. Plant Molecular Biology DOI 10.1007/s11103-014-0172-2 Pérez-Pacheco, R., Platzer, E.G., Woodward, D., Hyman, B.C. 2014. Bioassays for comparative infectivity of mermithid nematodes (Romanomermis iyengari, Romanomermis culicivorax, and Strelkovimermis spiculatus) for culicine mosquito larvae. Biological Control 80: 113-118. doi: 10.1016/j.biocontrol.2014.09.012. Pottorff M, Li G, Ehlers JD, Close TJ, Roberts PA. 2013. Genetic mapping, synteny, and physical location of two loci for Fusarium oxysporum f. sp. tracheiphilum race 4 resistance in cowpea [Vigna unguiculata (L.) Walp]. Molecular Breeding doi:10.1007/s11032-013-9991-0. Powers, T.O., E.C. Bernard, T. Harris, R. Higgins, M. Olson, M. Lodema, P. Mullin, L. Sutton, & K.S. Powers. 2014. COI haplotype groups in Mesocriconema (Nematoda: Criconematidae) and their morphospecies associations. Zootaxa 3827 (2): 101–146. Radovich,T., A. Pant, I. Gurr, N. Hue, J. Sugano, B. Sipes, N. Arancon, C. Tamaru, B. Fox, K. Kobayashi, and R. Paull. 2012. Innovative use of locally produced inputs to improve plant growth, crop quality, and grower profitability in Hawai'i. HortTechnology 22:738-742. Robbins, R. T., 2013. A History of the Reniform Nematode in the South. Southern Soybean Disease Workers, March 14, 2013. Robbins, R. T., E. Shipe, G. Shannon, P. Chen, S. K. Kantartzi, L. E. Jackson, E. E. Gbur, D. G. Dombek, and J. T. Velie. 2013. Reniform Nematode Reproduction on Soybean Cultivars and Breeding Lines in 2012. Proceeding of the 2013 Beltwide Cotton Conferences, San Antonio, Texas, January, 2013. Pgs. 129-137. Robbins, R. T., G. Shannon, P. Chen, S. K. Kantartzi, L. E. Jackson, E. E. Gbur, D. G. Dombek, J. T. Velie, and T. R. Faske. 2014. Reniform Nematode Reproduction on Soybean Cultivars and Breeding Lines in 2013. Proceeding of the2014 Beltwide Cotton Conferences, New Orleans Jan 6-8. Pgs. Robbins, R. T., G. Shannon, P. Chen, S. K. Kantartzi, L. E. Jackson, E. E. Gbur, D. G. Dombek, J. T. Velie, and T. R. Faske. 2014. Reniform Nematode Reproduction on Soybean Cultivars and Breeding Lines in 2013. Proceeding ofthe2014 Beltwide Cotton Conferences, New Orleans Jan 6-8. Pgs. Roberts PA, Ehlers JD, Huynh BL. 2013. Blackeye Varietal Improvement. p. 21-29. In University of California Dry Bean Research 2012 Progress Report, California Dry Bean Advisory Board, Dinuba, CA. Roberts PA, Huynh BL, Frate C. 2014. Blackeye Varietal Improvement. p. 41-49. In University of California Dry Bean Research 2013 Progress Report, California Dry Bean Advisory Board, Dinuba, CA. Rothrock C. S., S. A. Winters, J.D. Barham, A. B. Beach, M. B. Bayles, P. D. Colyer, T. Kelley, R. C. Kemerait, G.W. Lawrence, K. S. Lawrence, G.B. Padgett, P. M. Phipps, G. L. Sciumbato, R. Thacker, and J. E. Woodward. 2014. Report of the Cottonseed Treatment Committee for 2013. Proceedings of the Beltwide Cotton Conference, Vol. 1:249-255. National Cotton Council of America, Memphis, Tennessee. http://www.cotton.org/beltwide/proceedings/2005-2013/index.html Rudolph, R., Uchanski, M. E., Sams, C. E., Steiner, R. L., Thomas, S., Walker, S. Biofumigation performance of four Brassica crops in a green chile pepper (Capsicum annuum) rotation system in southern New Mexico. HortScience, (in press). Sanchez, K. R. 2014. The role of terrestrial mollusks in phoresis and vectoring of plant parasites. Ph.D. Dissertation, University of California, Davis, CA 95616 USA. Schrimsher, Drew W., Kathy S. Lawrence, Roelof B. Sikkens, and David B. Weaver. 2014. Nematicide enhancement of Rotylenchulus reniformis resistant cotton genotypes. Journal of Nematology 46:(In Press). Schroeder, J., Thomas, S., Beacham, J., Holland, L., Morris, E., Schmidt, N. E., Murray, L., Hanson, S. F. (2014). A presently-undetermined Meloidogyne species was found to parasitize yellow and purple nutsedge: should we be concerned? Weed Science Society of America Proceedings Vol. 54: 85. Sikkens, R.B., K.S. Lawrence, D.W. Schrimsher, S.R. Moore and D.B. Weaver. 2014. Upland cotton germplasm lines with introgressed resistance to the reniform nematode. Journal of Nematology Vol. 46:235-236. Smith, A. L., K. S. Lawrence, K. Glass, and J. Hu. 2014. Identification of Fusarium oxysporum f. sp. vasinfectum races present in Alabama cotton fields. (In Press) The American Phytopathological Society, St. Paul, MN. Smith, A. L., K. S. Lawrence, K. Glass, and E. van Santen. 2014. Cotton Cultivar Evaluations for Resistance to Fusarium Wilt and Root-knot Nematode Disease Complex in Alabama. Proceedings of the 2014 Beltwide Cotton Conference Vol. 1: 261-265. National Cotton Council of America, Memphis, TN. http://www.cotton.org/beltwide/proceedings Smith, A. L., K. S. Lawrence, and S. Nightengale. 2014. Cotton seed treatment combinations for Fusarium wilt and root-knot nematode management in Alabama, 2013. Report 8: ST003 DOI:11.1094/PDMR07. The American Phytopathological Society, St. Paul, MN. Stephens, J.Y., R. Myers, J. Lichty, K. Sewake, and B. Sipes. 2014. Control of Radopholus similis in anthurium with spinosad, spirotetramat, and thiophanate-methyl. Phytopathology (Supplement): 187-P. Thuo, A.K., Kimenju, J.W., Kariuki, G.M., Karuku, G.N., Wendot, P.K. and Melakeberhan, H. 2014. Seasonal variations of nematode assemblages and diversity in Virtisols, Cambisols and Arenosols soil groups in Kenya. 6th International Congress of Nematology, Cape Town, South Africa. Journal of Nematology 46: 247. Ulloa M, Hutmacher RB, Roberts PA, Wright SD, Nichols RL, Davis RM. 2013. Inheritance and QTL mapping of Fusarium wilt race 4 resistance in cotton. Theoretical and Applied Genetics 126:1405-1418. Van den Berg E, Tiedt LR, Coyne DL, Ploeg AT, Navas-Cortés JA, Roberts PA, Yeates GW, Subbotin SA. 2013. Morphological and molecular characterization and diagnostics of some species of Scutellonema Andrássy, 1958 (Tylenchida: Hoplolaimidae) with a molecular phylogeny of the genus. Nematology 15:719-745. Waisen, P. and B. Sipes. 2014. The effect of spirotetramat (Movento®) against reniform nematode, Rotylenchulus reniformis, on pineapple, Ananas comosus. Phytopathology (Supplement):53-O Xiang, N., K. S. Lawrence, J. W. Kloepper, and J. A. McInroy. 2014. Biological control and plant growth promotion of Bacillus spp. on Meloidogyne incognita in cotton. 2014. (In Press) The American Phytopathological Society, St. Paul, MN. Xiang, N., K. S. Lawrence, J. W. Kloepper, and J. A. McInroy. In vitro screening of biological control agents on Meloidogyne incognita. 2014. Proceedings of the 2014 Beltwide Cotton ConferenceVol. 1: 258-260. National Cotton Council of America, Memphis, TN. http://www.cotton.org/beltwide/proceedings Xiang, N., K.S. Lawrence, and C. Norris. 2014. Soybean nematicide combinations for reniform nematode management in north Alabama, 2013. Report 8: N009. DOI: 10.1094/PDMR08. The American Phytopathological Society, St. Paul, MN. Xiang, N., K.S. Lawrence, D. Schrimsher, and S. Nightengale. 2014. Evaluation of Poncho Votivo, Aeris, Temik, and UFS0 738 on cotton for root knot management in Alabama, 2013. Report 7:N005. DOI: 10.1094/PDMR07. The American Phytopathological Society, St. Paul, MN. Xiang, N., K.S. Lawrence, D. Schrimsher, and S. Nightengale. 2014. Evaluation of Temik, Aeris, and two experimental compounds on cotton for root knot management in Alabama, 2013. Report 7:N006. DOI: 10.1094/PDMR07. The American Phytopathological Society, St. Paul, MN. Yilma, S., R.E. Ingham, N. Wade, E. Karaagac, C.R. Brown, and M.I. Vales. 2013. Validation of Molecular Markers Associated with Resistance to the Colombia Root-Knot Nematode (Meloidogyne chitwoodi) and their Utilization in Potato Breeding. American Journal of Potato Research 90:156. Zasada, I.A., A. Peetz, N. Wade, R. A. Navarre, and R. E. Ingham. 2013. Host status of different potato (Solanum tuberosum) varieties and hatching in root diffusates of Globodera ellingtonae. Journal of Nematology 45:195-201. Zbylut, J., Murray, L., Thomas, S., Beacham, J., Schroeder, J., Fiore, C. Modeling ratios with potential zero-inflation to assess soil nematode community structure. Proceedings of the 25th Annual Kansas State University Conference on Applied Statistics in Agriculture, 25: (in press).

Impact Statements

The research reported here represents a novel report of the phoretic relationship between terrestrial mollusks and plant pathogens, particularly plant-parasitc nematodes. This novel report that snails may vector plant-parasitic nematodes has ramifications for integrated pest management, quarantine practices, and international trade. Results have been communicated to peer scientists professionals involved in agricultural production in various capacities through presentations at professional meetings and conferences.
A new species of cyst nematode, Globodera ellingtonae, has been found in potato fields in Oregon and Idaho. Very little is known about the biological properties of this species and its potential pathogenicity to potato or other crop plants. Research on this project will determine the level of concern that must be taken. Results reported here would indicate that G. ellingtonae may not be pathogenic to ?Desiree? but may be a weak pathogen to ?Russet Burbank? at high densities.
Reniform nematode when present in high numbers can reduce cotton yield in excess of 30%. There is no commercial cotton variety with resistance to this nematode. At present the only available reniform controls are crop rotation and with often ineffective chemical nematicides further limited by the EPA suspension of aldicarb. Rotation with a reniform nematode resistant soybean is a viable and economic option for those soybean and cotton producers with damaging numbers of reniform nematode.
Using highly resistant soybean in lieu of a susceptible soybean variety showed an increase of 6.8 Bushels per acre amounting to over $102 per acre increase in 2012 with the input costs the same.
We are developing both genetic and practical laboratory approaches that further the employment of entomopathogenic nematodes as practical, durable, and cost-effective biological control agents of mosquitoes.
Discovery of a unique DNA replication system within nematode mitochondria is an impacting finding; no longer can mtDNA be thought to replicate only by a D-loop mechanism. This finding indicates that fundamental molecular genetic processes differ across phyla and that it cannot simply be assumed that experimental approaches designed to impact nematode control can simply be adapted from our understanding similar processes in other pests. Proteins novel to this unique replication mechanism may be useful targets for pest management.
These studies provide an understanding of how agronomic practices change soil biology and nutrient cycling the biology and soil health management strategies: a) established basis for identifying the biotic and abiotic factors of nematode adaptation and parasitic variability, leading to understanding basic aspects of the biological interactions and developing location-specific and applied solutions; b) developing an integrated understanding of the relationships among cover and rotation crops, nematode community, and changes in soil conditions are critical to growers making accurate decisions; c) identifying the biotic and abiotic factors of nematode adaptation and parasitic variability, leading to understanding basic aspects of the biological interactions and developing location-specific and applied solutions.
An undergraduate student gained knowledge and skill in working with plant-parasitic and entomopathogenic nematodes.
Horticultural scientists were trained in one-on-one development of nematode collecting methods and nematode data analyzing.
Scientists and growers have information on nematode control alternatives in spinosad and imidocloprid.
Genetic variability in nematodes for ability to reproduce on resistant plants is being characterized to help guide decisions on use of resistant crop varieties and to give direction to plant breeding programs for grain legumes and cotton.
New combinations of resistance genes hold promise for developing crop varieties with stronger and broader nematode resistance. Nematode resistance traits in cowpea (blackeyes) are being introgressed through backcrossing via a combination of SNP marker genotyping in and field and greenhouse phenotyping screens. A set of advanced breeding lines has entered the field performance testing stage to determine which lines to release for commercial production in California and other dry grain production areas.
Enhanced resolution of resistance gene genetic map locations in cotton has important potential for improving nematode management in cotton. A suite of resistance loci for suppressing both root-knot nematodes and Fusarium wilt races 1 and 4 has been identified and closely linked markers have been used to select breeding lines carrying multiple resistance traits.
The molecular and morphological analysis of members of the genus Scutellonema will aid in diagnostics and potential import and export issues regarding this genus.
DNA-based identification of Ditylenchus species using the 18S ribosomal gene segment provides plant regulatory officials with definitive separation of the two quarantine-important species D. dipsaci from D.destructor and both from non-pathogenic soil-inhabiting Ditylenchus species. However, inclusion of ITS1and ITS2 sequences are necessary to differentiate the quarantine pest D. gigas from D. dipsaci.
A new Meloidogyne species found co-infesting agricultural land in southern NM should pose no economic threat to common summer annual crops such as cotton, chile, corn, and onion in the region. However, alfalfa, small grains, and certain turf grasses are hosts. Potential pathogenicity on this new species to these plants needs to be determined.
Use of the turf nematicide Avid® can manage severe bentgrass decline on golf greens associated with high populations of certain ectoparasitic nematodes.
Rotylenchulus reniformis resistance breeding in cotton will focus on BARBREN-713 source of resistance.
New nematicides being released are proving effective in crop production.
Rotylenchulus reniformis is reducing cotton yield by 60% in Alabama.
Molecular techniques are identifying genes used in parasitic reaction by the soybean cyst nematode. These will be useful in developing soybean varieties with resistance to this serious nematode pest.
Continued field experimentation with new and existing nematicides is a necessity to provide our agricultural producers with a short term management tools for nematode pests.
DNA barcoding will be the future of pest species identification. It is entirely dependent on the quality of the reference database and the analytic process. Optimizing these components will result in accurate identifications and scientifically well-informed regulatory decisions.

Date of Annual Report: 02/15/2016

Report Information

Annual Meeting Dates: 11/05/2015 - 11/06/2015
Period the Report Covers: 10/01/2014 - 09/30/2015

Participants

Hafez, Saad (shafez@uidaho.edu) – Univeristy of Idaho; Ingham, Russell (inghamr@science.oregonstate.edu) – Oregon State University; Lawrence, Gary (glawrence@entomology.msstate.edu) – Mississippi State University; Lawrence, Kathy (lawrekk@auburn.edu) – Auburn University; Melakeberhan, Haddish (melakebe@anr.msu.edu) – Michigan State University; Powers, Thomas (tpowers1@unl.edu) – University of Nebraska; Robbins, Robert (rrobbin@uark.edu) – University of Arkansas; Roberts, Philip (philip.roberts@ucr.edu) – University of California, Riverside; Sipes, Brent (sipes@hawaii.edu) – University of Hawaii; Klink, Vincent (vklink@biology.msstate.edu) – Mississippi State University; Zasada, Inga (Inga.Zasada@ars.usda.gov) - USDA-ARS Horticultural Crops Research Laboratory; Adams, Byron (byron_adams@byu.edu) - Brigham Young University

Brief Summary of Minutes

Minutes Attachment:

W3186-Minutes 12192015 final.pdf

Accomplishments

Objective 1:   Characterize genetic and biological variation in nematodes relevant to crop production and trade.  Alabama (Lawrence): Germplasm lines from the BARBREN and M713 groups derive this resistance to reniform nematode from a common source: wild accession GB-713 of G. barbadense. This commonality in background is reflected in the excellent results of all three parts of this study. All lines of these two groups yielded well under nematode free conditions, with BAR 41 matching those of conventional cultivar FM966. Yield reductions due to reniform nematode exposure were less than 10% for BAR 41 and all five M713 lines. The three MT2468 lines also reduced nematode reproduction, but suffered significant yield reductions of 50 to 70%, about equal to the yield losses sustained by the two susceptible controls. The high level of reniform susceptibility found in a limited number of LONREN individuals might indicate seed contamination due to outcrossing. The rapid assessment experiment on microplots yielded results which closely mimicked those obtained from the more elaborate field and greenhouse trials. Arkansas (Robbins): In a greenhouse test for hosts of an Arkansas population of Meloidogyne partityla I tested Pecan (Very good Host); Eastern Black Walnut (Juglans nigra) host, Shagbark Hickory (Host); Southern Red Oak (Host); Burr Oak (?) and Pin Oak (?). More host test are started for several other tree species.  Efforts to identify Meloidogyne species of Arkansas are ongoing. No new species since the 2014 report.  I worked with soybean researchers from Missouri and Georgia to identify 27 soybean Plant introductions reported to have Soybean Cyst Nematode resistance for reniform nematode reproduction (resistance). Of the 27 PI’s six were resistant to reniform.  I have been testing reniform resistant lines of cotton with a seed company with the goal of finding lines with both reniform and root-knot resistance present. California – Riverside (Roberts): Carrots are highly susceptible to several species of root-knot nematodes, which cause forking and galling distortion of the marketable taproot. A panel of eleven resistant carrot lines representing the known range of resistance sources to the common Melodiogyne spp. was screened in greenhouse pot tests with 45 Meloidogyne species isolates, including 29 of M. incognita, 11 of M. hapla, and others of M. javanica and M. arenaria. Overall resistance levels of some lines with known M. incognita resistance genes was effective against all isolates. The best sources of resistance were Brasilia (gene Mj-1 combined with additional M. incognita genes; and combinations of Brasilia and Homs resistance sources). The most virulent isolates causing slightly elevated root galling were still effectively controlled by the resistance. Some lines known to be virulent on the tomato resistance gene Mi-1.2 were not virulent on any of the resistant carrot lines in the panel. The most resistant taproots from these tests are being grown for selfing or crossing at the USDA, Madison WI carrot breeding program (P. Simon) to advance the development of RKN resistant carrot varieties for growers.  Hawaii (Sipes): Breadfruit (Artocarpus altilis) is rapidly becoming a popular landscaping and food crop in Hawaii. Plant-parastic nematodes associated with breadfruit include Pratylenchus, Helicotylenchus, and Meliodogyne. On the islands of Kauai and Maui in Hawaii, Helicotylenchus spp. was dominant in all of the samples collected. Rotylenchulus and Paratylenchus were found in low populatons but were present in all soil samples. Other plant-parasitic nematode genera in the breadfruit-associated soils in Hawaii included Scutellonema, Pratylenchus, Mesocriconema, and Meloidogyne. A heteroderid nematode was also found in samples from Kauai and Maui. The population density and genera of plant-parasitic nematodes found in Hawaiian breadfruit soils could indicate damage to the crop and aid in developing a specific management approach for local growers and farmers of breadfruit. In addition to expanding the locations, collection and extraction from breadfruit roots would help elucidate which nematodes infect and parasitize breadfruit in Hawaii. Michigan (Melakeberhan): Understanding nematode adaptation in mixed cropping systems and developing suitable nematode and crop yield management strategies is highly complex. In part, the difficulties arise from the agronomic practices (e.g. tillage, crop rotation, cover crop use and agricultural inputs) varying impacts on soil health, defined as the biological, physiochemical, nutritional, structural and water holding integrity of a given soil. While soil health directly or indirectly affects biological interactions, how agronomic practices exactly influence soil biology, which drives the soil food web and nutrient transformations, is less known. Comparative analyses of different cropping systems and land use practices suggest that critical factors that affect beneficial nematodes, indicator of soil health, and presence of harmful nematodes and their adaptation therein may be overlooked. First, on-going is a long-term study to determine how soybean cyst nematode (SCN, Heterodera glycines) adapts when introduced into a new location under till and no-till, and either corn (Zea mays, C), SCN race 3 resistant soybean (R, Glycine max), or susceptible soybean (S) monocrop, or RCRC and SCSC rotations. While SCN population density was lower in no-till than in tilled treatments, and highest in S and lowest in C or RC rotations, it was detected at less than one cyst per 100 cc of soil. This suggests a prolonged phase of decline from the introduced levels. Interaction effects of tillage, rotation and/or time on SCN suggest that outcomes vary by agronomic practice and time, providing agro-biologically based understanding of SCN establishment in a new location. Second, we examined how sugar beet varieties (EL53, EL57, EL59, EL61 and EL64 from the USDA laboratory at MSU) along with soybean and corn (standard rotation crops) affect sugar beet cyst nematode (SBCN) and other herbivore nematodes and soil health in different soil types in 2012 and 2013. Cyst and other herbivore nematode population dynamics, and soil food web data support the hypothesis that there are distinct interactions among the crops, nematodes and soil conditions. Third, how sugar beet (SBCN-tolerant, B-18RR4N and –susceptible, B-10RR34), cover and trap (oilseed radish: Defender and Tillage; mustard: Pacific Gold and Ida Gold)) crops, and soybean (SCN-resistant 92Y80 and SCN-susceptible 92M91) and corn (P9910R) affect soil health, nematode community and sugar beet production in sandy clay loam and loam soils was studied in 2013 and 2014. While the sandy clay loam soil was more stressed than the loam soil, principal component analysis showed distinct correlation patterns among nematode community indices and physiochemical properties in the soil types. Fourth, whether it was undisturbed (pristine forest or natural vegetation) or disturbed (agricultural or grazing) landscapes in Ferralsol, Lithosol and Nitosol soil groups, the herbivore nematodes Amplimerlinius, Heterodera and Trophurus in Ghana, Paratrophurus in Kenya, and Trichodorus and Longidorus in all three countries were present in Ferralsols only. Furthermore, multi-factor correlation analyses of nematode abundance and frequency, soil texture and physiochemical properties showed distinct separation of the soil groups and by country, and Ferralsols further from Lithosols and Nitosols. Although all biologically degraded, the results indicate that these soil groups have different biological properties and may not respond the same way to a given treatment. Collectively, the studies point to understanding the soil environment might be a key factor in determining nematode adaptation. Thus, providing basis for further investigations that might shed light on specificity of interactions at micro- and macro-environment levels. On-going are studies to characterize distribution and parasitic variability of the northern root-knot and cyst nematodes in the diverse Michigan cropping systems. Mississippi (Lawrence & Klink): Genes functioning in membrane fusion were originally identified genetically in the baker’s yeast, Saccharomyces cerevisiae, and are found in all eukaryotes. Components of the membrane fusion unit function in the plant genetic model Arabidopsis thaliana during its defense to shoot pathogens. Regarding defense, little is understood about a root function. Experiments in Glycine max (soybean) have provided an opportunity to perform such studies, revealing that syntaxin 31 and alpha soluble NSF attachment protein (-SNAP) are expressed under natural conditions in root cells undergoing defense to parasitism by the nematode Heterodera glycines. Other genes functioning in membrane dynamics are also expressed, but have no obvious role in root biology or resistance. Presented here, G. max homologs of membrane fusion genes are shown to function in the resistance of G. max to H. glycines. In contrast, other genes functioning in various aspects of vesicle transport do not appear to function in resistance. These experiments point to the specificity of the transgenic approach used in the analysis and the process of resistance itself. Experiments show that the membrane fusion apparatus functions with a number of other genes during the process of resistance. Nebraska (Powers) : We have continued to work on DNA barcoding for nematode identification and the construction of a reference database for DNA barcodes of plant parasitic nematodes. This past year we have focused on Pratylenchus species. We have been testing newly designed primer sets for COI which amplify 1000bp of the mitochondrial gene. Notable results include the observation that many agricultural fields in Great Plains and the Midwest contain a mixture of discrete haplotypes regardless of host. This means that many fields may have species mixtures that may favor different hosts in a crop rotation or may have specific weed hosts. We have recovered five primary haplotype groups in the region. One group appears to correspond to Pratylenchus penetrans and a second corresponds to P. thornei. A third group corresponds to what might be considered P. neglectus, P. scribneri, or P. hexincisus. The morphological characters that discriminate these there species do not appear to correspond to COI haplotype grouping. Specimens from each of the five haplotype groups have been associated with corn fields. We will continue to collect and analyze specimens from a wider geographic range. New Mexico (Thomas & Hanson): In collaboration with Dr. S.F. Hanson’s lab, we investigating the feasibility of using deep sequencing methodologies to detect and identify Ditylenchus and Meloidogyne species in a manner suitable for use in examining high numbers of soil samples in a cost-effectively.  A standardized protocol was developed which reproducibly recovers high quality DNA from bulk nematode populations isolated from soil samples.  The procedure is a hybrid that begins with the high efficiency lysis of bulk nematode samples using the lysis procedure we previously developed for single nematodes.  This is followed by an affinity column purification step adapted from a commercial soil DNA purification kit (Power soil, Mo Bio Inc) to remove PCR inhibitors like humic acid from organic debris that is present in DNA prepared from bulk nematode samples.  We are currently running this procedure in a microfuge tube format that can process 24 samples in parallel in about 2 hours.  A single trained technician could feasibly extract DNA from 48-72 samples per day using this procedure.  Multiple tests showed that this procedure reliably produces PCR quality DNA whereas the lysis procedure on its own failed ~1/3 of the time.   We also designed primer sets and PCR profiles that allow amplification of PCR products that span an 1,800 bp region bridging 18S, ITS-1, 5.8S, ITS-2, and a portion of the 28S rRNA genes.  This span enables species level identification for Ditylenchus and meiotically-parthenogenetic Meloidogyne species using a single contiguous amplicon in a mixed sample without having to assemble sequences from different amplicons in-silico after sequencing.  These primers enabled positive identification of Meloidogyne chitwoodi and D. dipsaci from multiple samples submitted to the NMSU Nematode Containment Facility by the NM Department of Agriculture. Oregon (Ingham): Biological characterization of Globodera ellingtonae.  On April 28, 2008, a field at the Oregon State University Powell Butte Farm that was planted to potato in 2007 was sampled and found to contain cysts of Globodera which were morphologically and molecularly distinct from golden potato cyst (G. rostochiensis), pale potato cyst (G. pallida), and tobacco cyst (G. tobaccum) nematodes.  Subsequently, in August and September of 2008 cysts matching the characteristics of those found at Powell Butte were recovered from two grower potato fields in Idaho.  These nematodes were later (2012) described as a new species, G. ellingtonae.  Very little is known about the biological properties of this species and its potential pathogenicity to potato or other crop plants.  Lab, greenhouse, and field studies have begun to help characterize the biology of G. ellingtonae. To evaluate the pathogenic effects of G. ellingtonae on potato, six field trials over a four-year period were conducted.  In three trials (2012, 2013, 2014), single hills of potato ‘Russet Burbank’ were planted into soil infested with different initial densities (Pi) of G. ellingtonae (0, 5, 10, 20, 40, or 80 eggs/g soil) at the Central Oregon Agriculture Research Center farm at Powell Butte, OR.  In 2013, the trial was repeated with the red potato variety, ‘Désireé’.  In another trial (2014), five additional potato varieties varying in maturity lengths were either inoculated (80 eggs/g soil) or not with G. ellingtonae.  All trials were planted in a randomized block design with 7 or 8 replications on a 76 cm in-row spacing between plants.  At harvest, tops were removed, dried and weighed (2013 and 2014), and tubers were dug by hand and weighed.  Soil samples were taken from beneath each plant; cysts were extracted and crushed to determine the eggs per g soil (Pf).  Pf densites for Pi densities of 5, 10, 20, 40, and 80 eggs/g soil averaged 104, 121, 177, 234, and 229 eggs/g soil, respectively, for the four trials with variable Pi.  This suggests that some limit in nematode reproduction may have been reached between 40 and 80 eggs/g soil.  Only one of the trials (2013) conducted with increasing levels of Pi, resulted in a significant negative correlation between Pi and yield of ‘Russet Burbank’.  Combining data from the three years of ‘Russet Burbank’ trials in a multiple linear regression model indicated a significant effect of Pi on tuber yield.  Based on the linear regression model of tuber yield on log(Pi) with a single slope for the three Russet Burbank trials, 11.3 to 17.0% yield loss is predicted at a Pi of 40 eggs/g soil and 13.5 to 20.2% yield loss is predicted at a Pi of 80 eggs/g soil when tuber yields at Pi of 0 eggs/g soil are 1,829 to 2,744 g/plant.  None of the potato varieties (‘Russet Norkotah’, ‘Yukon Gold’, ‘Ranger Russet’, ‘Alturas’, ‘Umatilla Russet’) inoculated with 80 G. ellingtonae eggs/g soil had significantly reduced top weights or tuber yields compared to non-inoculated plants.  In 2015, one of these varieties (‘Ranger Russet’) was planted into soil infested with a range of very high initial densities (Pi = 0, 40, 80, 160, and 320 eggs/g soil) to see if an impact on yield could be determined at these densities.  Only top and tuber weights from the 320 eggs/g soil infestation level were significantly less than for plants grown in uninfested soil.  Care should be taken in extrapolating the results from this single field site to probable effects of G. ellingtonae on potato in other environments.   Objective 2:  Determine nematode adaptation processes to hosts, agro-ecosystems and environments. Alabama (Lawrence) Fusarium oxysporum  f. sp. vasinfectum (W. C. Snyder & H. N. Hansen) causes economic losses of Upland cotton (Gossypium hirsutum) yields throughout the cotton belt of the United States. An association with the Southern root-knot nematode (Meloidogyne incognita) was recognized early on in the discovery of the disease, forming a disease complex. Trials to screen commercially available cultivars for resistance or tolerance to the Fusarium wilt disease complex have indicated that the root-knot nematode is the disease pathogen driving the disease complex as measured by yield reduction.  Ranking the cultivars by yield indicated the highest yielding cultivars were Stoneville 4747 GLB2 followed by Phytogen 427 WRF, Phytogen 499 WRF, and Stoneville 4946 GLB2.  Phytogen 427 WRF, Stoneville 4946 GLB2 and Phytogen 499 WRF supported lower root-knot populations and little FOV disease incidence.  Stoneville 4747 GLB2 supported very low wilt incidence, but root-knot egg reproduction factors were not significant.  Deltapine 1454NR B2RF supported lower numbers of root-knot nematode eggs per gram of root fresh weight than the susceptible check Rowden and other commercial cultivars tested in the trial.  This variety performed the best when limiting root-knot nematode reproduction, but could be considered moderately susceptible to Fusarium wilt.  Race 1 was the predominant race found in Alabama, with 70% of isolates identifying as this race. 14% of isolates were LA 108, 8% were race 8, 7% were LA 127/140, and 0.008% were identified as race LA 110. New Mexico (Thomas): The study established in late 2013 and repeated in 2014-2015 to determine if the previous crop species affects subsequent M. incognita reproduction on yellow and purple nutsedges was completed.  Analysis of data is in progress.  These studies are necessary to accurately predict how different cropping scenarios will impact root-knot nematode carryover to future crops from perennial weeds.  In both studies nutsedges were inoculated with eggs recovered from cotton, chile, or corn (the major summer annual crops in southern NM).  Inoculum from tomato was also included to allow extrapolation to results from previous studies.  The experiments are harvested upon accumulation of 750 heat units (DD24 = one life cycle for the nematode), and eggs extracted from roots.  Results will be used to calculate the crop-specific M. incognita carryover potentials for both nutsedge species for use to develop IPM management recommendations for the nutsedge/nematode pest complex. The percentage of yellow or purple nutsedge tubers that harbored M. incognita was not affected by crop, suggesting that tubers from both nutsedge species provide a consistent reservoir of nematodes to infect future crops.  In a separate series of experiments begun in Fall 2015, the Ditylenchus dipsaci population detected in a large-scale home garlic production system are being examined for potential to infect regional varieties of alfalfa and commercial bulb onions.  Utah (Adams): Parasitism is a major ecological niche for a variety of nematodes. Multiple nematode lineages have specialized as pathogens, including deadly parasites of insects that are used in biological control. We have sequenced and analyzed the draft genomes and transcriptomes of the entomopathogenic nematode Steinernema carpocapsae and four congeners (S. scapterisci, S. monticolum, S. feltiae, and S. glaseri).  We used these genomes to establish phylogenetic relationships, explore gene conservation across species, and identify genes uniquely expanded in insect parasites. Protein domain analysis in Steinernema revealed a striking expansion of numerous putative parasitism genes, including certain protease and protease inhibitor families, as well as fatty acid- and retinol-binding proteins. Stage-specific gene expression of some of these expanded families further supports the notion that they are involved in insect parasitism by Steinernema. We show that sets of novel conserved non-coding regulatory motifs are associated with orthologous genes in Steinernema and Caenorhabditis. To assess the impact of FTCs on cold-adapted soil biota, we evaluated freeze-thaw dynamics (i.e., 0°C crossings) and demographics of the dominant nematode, Scottnema lindsayae, (proportion of adults, population size) over 20 years in soils at two locations in Taylor Valley, Antarctica. Based on hourly soil temperature data, we demonstrate that FTCs are a frequent feature in Taylor Valley, but with high inter-annual and spatial variability. Valley topography and soil moisture were found to impact FTC frequency, suggesting that basins within Taylor Valley have different susceptibilities to environmental variability. Increased FTC frequency in 1999–2001 coincided with a shift in S. lindsayae populations, with fewer juveniles reaching maturity. In the years following decreased adult proportions, overall S. lindsayae numbers were reduced, implying a strong negative effect of FTCs on in situ recruitment. Our results suggest that increased FTC frequency in the Dry Valleys slows S. lindsayae development, reducing reproductive success and may take years to impact population size, which demonstrates the importance of long-term research to accurately predict the consequences of climate change on soil biota and biogeochemical cycling in the cold regions.   Objective 3:  Develop and assess nematode management strategies in agricultural production systems. Arkansas (Robbins) Annually I test all new soybean entries submitted to the Arkansas Soybean Variety Testing Trials for reniform nematode reproduction. In 2015 this was 116 entries. A single plant of each variety was grown in each of 5 separate 4 inch diameter clay pots. As a germinated seedling was transplanted into each pot it was inoculated with 2,000 vermiform reniform nematodes. Two resistant varieties (Hartwig and Anand) were used as resistant checks while Braxton and Ellis was used as the susceptible checks. One pot in each rep was inoculated and left fallow as a check on reniform survival. The test was terminated after 12 weeks. Of the 116 entries there were seven that did not differ in reproduction than the resistant varieties Hartwig and Anand) and have probable rotation usefulness. Similar tests were also done for 219 varieties and breeding lines submitted by Southern Public Soybean Breeders from Arkansas (Chen), Southern Illinois (Kantartzi), Missouri (Shannon), and Georgia (Li). Of the 219 entries, 19 were as resistant as the resistant varieties Anand and Hartwig.  The specifics including statistical analysis (RTR) will be reported at the Beltwide Cotton Conferences in New Orleans in January 2016. Hawaii (Sipes): Reniform nematode, Rotylenchulus reniformis, is a major pest of pineapple in Hawaii, reducing pineapple marketable yield by 26.8-50%. We determine if spirotetramat was active against reniform nematode in greenhouse and in vitro assays. Tomato plants were also treated 7-dpi and terminated at 14-dpt or 21-dpi to assess penetration. Reniform nematode eggs were also subjected to the spirotetramat in vitro to assess hatching. At 200 g a.i/ha, pineapple above ground biomass increased by 34.27% and root growth increased by 43.05% while reducing the root nematode population by 92.65% compared to untreated control. Nematode penetration at 50 or 100 g a.i/ha did not occur. Hatching was comparable in all treatments. Among all the treatment rates, 200 g a.i/ha significantly reduced the nematode population and enhanced the plant growth. No effect on hatch indicated that spirotetramat is only active through ingestion. In Odisha, India, as in many developing regions, the adoption rate of innovative farm technology is low as the farmers are generally risk averse. Traditional agricultural practices include multiple plowings for land preparation, mono-cropping, and fallowing the land after two cropping seasons. This traditional farming system is not sustainable, particularly on hilly slopes, where the current practices result in soil erosion and sub-optimal production. Conservation Agriculture Production Systems (CAPS) have been proven to work in other countries with similar environments. Finding early adopters to practice CAPS on their fields will help achieve higher adoption rates, as early adopters can influence other farmers. A survey for farmers in Rudhiapada and Badamahulidiha uncovered socio-economic determinants of early adopters. Forty six tribal farmers were surveyed to determine whether the farmers adopted a previously-introduced high yielding maize cultivar technology and to assess these farmers' profiles. Among these farmers, 50% had adopted the maize technology. By knowing the determinants of these early adopters, decision makers and extension can target farmers as leaders and early practitioners of desirable practices such as CAPS. Idaho (Hafez): 2015 three new products for the management of mint nematodes were field tested in two irrigation systems, drip-line and furrow. Products were applied by injection for drip-line or foliar application for furrow irrigation. A single application of each chemical under each irrigation system was made. The field was allowed to grow under standard practice for the duration of the season. In September 2015 a 65 square foot area was harvested from each plot and weighed. 21 pounds of the sample were dried for oil extraction at the end of the season. Oil was extracted using a small University distillery and measured in milliliters. Data was compiled and means were separated using Duncan’s new multiple range test. Differences were only considered significant if P≤0.05. Data indicates that applications made in furrow irrigation systems may result in a higher hay yield as compared to the untreated control, however no significant difference in oil yield were found. Further study on field efficacy under different irrigation systems is planned for the 2016 season. A continuous survey of mint fields throughout Idaho and Eastern Oregon has provided a list of common nematodes and their relative population densities. Yearly spreadsheets are constructed that indicate species, density, county and city of extraction. Thus far data has determined that lesion nematodes are the most common mint nematodes and pin nematodes have the highest density. This survey is projected to continue through 2017. Greenhouse and microplot trials have started to determine the pathogenicity of pin nematode in mint. Trials will include determination of pin nematode thresholds and interactions with Verticillium wilt infection. Trials are in currently in their preliminary stages and are projected to see results in the near future. Michigan (Melakeberhan): On-going are efforts to refine the fertilizer use efficiency (FUE) model, which separates nutrient deficiency and toxicity from nematode (pest) suppression and agro-ecological efficiency. These include integrating the FUE model with the soil food web model, which describes soil conditions and nutrient transformations in response to treatment. Mississippi (Lawrence): Agricultural chemical companies are in the process of developing products designed for nematode control in row and vegetable crops. Efficacy studies have been conducted in 2015 with the products listed in Table 1 to determine their effect on nematode infestations of field crops. Many are still in their early developmental stages therefore only numbers or codes are available for some of the listed products. <table style="height: 500px;" border="yes" width="800"> <tbody> <tr> <td colspan="3" width="543">  Table 1. Experimental and Existing Nematicide Products by Company, Product and Application Method </td> </tr> <tr> <td colspan="2" width="359"> </td> <td width="184"> </td> </tr> <tr> <td style="text-align: center;" width="116"> Company </td> <td style="text-align: center;" width="243"> Product </td> <td style="text-align: center;" width="184"> Application </td> </tr> <tr> <td width="116"> Albaugh </td> <td width="243"> ALB-EXP5-1, ALB-EXP5-3 </td> <td width="184"> Seed treatment </td> </tr> <tr> <td width="116"> AMVAC </td> <td width="243"> Counter 20G (Terbufos) </td> <td width="184"> In-furrow granular </td> </tr> <tr> <td rowspan="3" width="116"> Bayer  </td> <td width="243"> Velum Total (Fluopyram + Imidacloprid) </td> <td width="184"> In-furrow spray </td> </tr> <tr> <td width="243"> Aeris seed applied system (Thiodicarb) </td> <td width="184"> Seed treatment </td> </tr> <tr> <td width="243"> Votivo (Bacillis firmis) </td> <td width="184"> Seed treatment </td> </tr> <tr> <td rowspan="3" width="116"> DuPont </td> <td width="243"> Vydate L (Oxamyl) </td> <td width="184"> In-furrow spray </td> </tr> <tr> <td width="243"> Vydate C-LV (Oxamyl) </td> <td width="184"> Foliar spray </td> </tr> <tr> <td width="243"> Q8U80 </td> <td width="184"> In-furrow spray </td> </tr> <tr> <td width="116"> Monsanto </td> <td width="243"> Numbers only (1-14) </td> <td width="184"> Seed treatment </td> </tr> <tr> <td width="116"> Marrone </td> <td width="243"> M305BM1 M305BM3 </td> <td width="184"> In-furrow spray </td> </tr> <tr> <td rowspan="2" width="116"> NuFarm </td> <td width="243"> Azadirachtin, Nematox, Senator </td> <td width="184"> Seed treatment </td> </tr> <tr> <td width="243"> Neem Oil, albendazole, Imidacloprid </td> <td width="184"> </td> </tr> <tr> <td width="116"> Syngenta </td> <td width="243"> Avicta Complete (abamectin) </td> <td width="184"> Seed treatment </td> </tr> </tbody> </table> New Mexico (Thomas):  A study begun in late 2013 to evaluate the efficacy of Avid® (2% abamectin) for management of severe damage to bentgrass greens at the University of NM golf course resulting from high populations of Mesocriconema spp., Pratylenchus spp., and Longidorus breviannulatus was continued in 2015.  Annual application at maximum rates continues to provide effective suppression of     Mesocriconema spp and Longidorus breviannulatus, maintaining populations below the damage threshold and enabling a return to full use of the course.  Populations of Pratylenchus continue to increase and show little response to treatment.  However, damage symptoms on greens have not been apparent.  In another study management of M. incognita was attempted in chile pepper using the bionematicide Huma Gro® PromaxTM, due to the lack of availability of oxamyl (the preferred treatment).  The product failed to provide suppression of soil populations measured at thinning (mid-June) or harvest (mid-September).

Publications

Journal Articles: Chen, P.,  C. P. Gray, T.L. Hart, M. Orazaly, J.C. Rupe, D.G. Dombek, R.D. Bond, T. Kirkpatrick, R.T. Robbins, and L.O. Ashlock. 2014. Registration of ‘UA 5612’ soybean.  J. of Plant Reg. 8(2):145-149. Chen, P., M. Orazaly, J.C. Rupe, D.G. Dombek, T. Kirkpatrick, R.T. Robbins, C. Wu, and P. Manjarrez. 2014. Registration of ‘UA 5213C’ soybean. J. of Plant Reg. 8(2): 150-154. Dillman, A. R., M. Macchietto, C. F. Porter, A. Rogers, B. Williams, I. Antoshechkin, M.-M. Lee, Z. Goodwin, X. Lu, E. E. Lewis, H. Goodrich-Blair, S. P. Stock, B. J. Adams, P. W. Sternberg, and A. Mortazavi. 2015. Comparative genomics of Steinernema reveals deeply conserved gene regulatory networks. Genome Biology 16:1-21. Huynh B.-L., W.C. Matthews, J.D. Ehlers, M. Lucas, J.P. Santos, A. Ndeve, T.J. Close and P.A. Roberts. 2015. A major QTL corresponding to the Rk locus for resistance to root-knot nematodes in cowpea (Vigna unguiculata L. Walp.). Theoretical and Applied Genetics: 1-9. DOI 10.1007/s00122-015-2611-0 Knox, M. A., D. H. Wall, R. A. Virginia, M. L. Vandegehuchte, I. S. Gil, and B. J. Adams. 2015. Impact of diurnal freeze–thaw cycles on the soil nematode Scottnema lindsayae in Taylor Valley, Antarctica. Polar Biology:1–10. Ingham, R.E., D. Kroese, and I.A. Zasada. 2015. Effect of Storage Environment on Hatching of the Cyst Nematode Globodera ellingtonae. Journal of Nematology 47:45-51. Lee, H. K., G. W. Lawrence, J. L. DuBien, and K. S. Lawrence. 2015. Seasonal variation and cotton-corn rotation in the spatial distribution of Rotylenchulus reniformis in Mississippi cotton soils. Nematropica 45:72-81.  <a href="http://journals.fcla.edu/nematropica/article/view/85053/81982">http://journals.fcla.edu/nematropica/article/view/85053/81982</a> Li, Ruijuan, Aaron M. Rashotte, Narendra K. Singh, Kathy S. Lawrence, David B. Weaver, and Robert D. Locy. 2015. Transcriptome Analysis of Cotton (Gossypium hirsutum L.) Genotypes That Are Susceptible, Resistant, and Hypersensitive to Reniform Nematode (Rotylenchulus reniformis. PONE-D-15-10976R2 Melakeberhan, H., Wang, W., Kravchenko, A. and  Thelen, K. 2015. Effects of agronomic practices on the timeline of Heterodera glycines establishment in virgin land. Nematology 17:705-713. Nair, M.G., Seenivasan, N., Liu, Y., Feick, R.M., Maung, Z.T.A. and Melakeberhan, H. 2015. Leaf constituents of Curcuma spp. suppress Meloidogyne hapla and increase bacterial-feeding nematodes. Nematology 17:353-361. Pant SR, McNeece BT, Sharma K, Nirula PM, Jiang J, Harris JL, Lawrence GW, Klink V.P. 2015. A plant transformation system designed for high throughput genomics in Gossypium hirsutum to study root-organism interactions. Journal of Plant Interactions 10:11–20 Pant SR, Krishnavajhala A, Lawrence GW, Klink VP. 2015. A relationship exists between the cis-Golgi membrane fusion gene syntaxin 31, salicylic acid signal transduction and the GATA-like transcription factor, LESION SIMULATING DISEASE1 (LSD1) in plant defense. Plant Signaling & Behavior 10:1, e977737 Rudolph, R.E., C. Sams, R. Steiner, S.H. Thomas, S. Walker, and M.E. Uchanski. 2015.  Biofumigant performance of four Brassica crops in a green chile pepper (Capsicum annuum) rotation system in southern New Mexico.  HortScience 50:247-253. Yongqing Jiao, Tri D. Vuong, Yang Liu, Zenglu Li, Jim Noe, Robert T. Robbins, Trupti Joshi, Dong Xu, J. Grover Shannon, and Henry T. Nguyen. 2015. Identification of quantitative trait loci underlying resistance to southern root-knot and reniform nematodes in soybean accession PI 567516C. Molecular Breeding (2015) 35:131 Zasada, I.A., R.E. Ingham, and W.S. Phillips. 2015. Biological insights into Globodera ellingtonae. In: Back. M., V. Block, I. Grove, S. Hockland and J. Pickup (eds). 4th Symposium of Potato Cyst Nematode Management (including other nematode parasites of potatoes). Aspects of Applied Biology 130: 42-47. Zhao, C., Y. Feng, R. Mathew, K. Lawrence, and S. Fu. 2015. Soil microbial community structure and activity in a 100-year-old fertilization and crop rotation experiment. Journal of Plant Ecology doi:10.1093/jpe/rtv007 <a href="http://gce.henu.edu.cn/images/Papers/zhao3.pdf">http://gce.henu.edu.cn/images/Papers/zhao3.pdf</a>   Published Abstract: Beacham, J. S. Thomas, J. Schroeder,  L. Holland, E. Morris, N. Schmidt, L. Murray, F. Solano-Campos, S. Hanson, and J.D. Eisenback.  2015. Host status of a new Meloidogyne species found parasitizing yellow and purple nutsedges. Journal of Nematology 47: (in press) Habteweld, A., Brainard, D., Ngouajio, M., Kravchenko, A., Grewal, S. P. and Melakeberhan, H. 2015. Integrating the concepts of fertilizer use efficiency and nematode-based soil food web models for broader use in soils health management. 54th Annual Meeting of the Society of Nematologists Program Abstracts. 52. Khanal, Churamani, R. T. Robbins, E. C. McGawley, and C. Overstreet 2015. Meloidogyne spp. reported from Arkansas: past and present. Program and Abstracts, 54th Annual Meeting of the Society  of Nematologists. East Lansing, Michigan Lawrence, K. S. and G. W. Lawrence. 2015. The fungicide fluopyram exhibits nematicide activity toward Rotylenchulus reniformis. Proceeding of the XVIII International Plant Protection Congress Belin, Germany, August 24-27, 2015. Vol. 1:241. <a href="http://domains.conventus.de/fileadmin/media/2015/ippc/IPPC2015_Abstractbook.pdf">http://domains.conventus.de/fileadmin/media/2015/ippc/IPPC2015_Abstractbook.pdf</a> Luangkhot, J. A., K.S. Lawrence, A.L. Smith. 2015. Evaluation of plant hormones and starter fertilizers on plant development in the presence of M. incognita or R. reniformis. 2015 Phytopathology 105:(In Press) Maung, Z.T.A., Poindexter, S., Clark, G, Stewart, S, Hubbell, L. and Melakeberhan, H. 2015. Effects of rotation and cover crops on nematode communities and soil health in different sugar beet production soils. 54th Annual Meeting of the Society of Nematologists Program Abstracts. 64. Maung, Z.T.A., Yildiz, S, Kimenju, W. Kwoseh, C, Saka, V. and Melakeberhan, H. 2015. Soil health in three African soil groups revealed by nematode community analysis. 54th Annual Meeting of the Society of Nematologists Program Abstracts. 63. Sundararaj, P. P. and S.L. Hafez. 2014. Effect of chemical nematicides on the management of Columbian root knot nematode Meloidogyne chitwoodi on potato. Presented in the AZRA Silber Jubilee International Conference “Probing Biosciences for Food Security & Environmental Safety” on 16-18 February, 2014, held at CRRI, Cuttack, India. Robbins, R. T., Ben Fallen, G. Shannon, P. Chen, S. K. Kantartzi, Travis R Faske, L. E. Jackson, E. E. Gbur, D. G. Dombek and J. T. Velie. 2015. Reniform Nematode Reproduction on Soybean Cultivars and Breeding Lines in 2014. Proceedings Beltwide Conferences 2015, San Antonio. Saad L. Hafez and Christeena H. Sevy. Efficacy and optimum application timing of Movento for management of sugar beet cyst nematodes in sugar beet, 2014. 54th Annual Meeting of the Society of Nematologist, Lansing, Michigan, July 19-24, 2015.   Saad L. Hafez and P. Sandararaj. Effect of Movento alone or in combinations with Vydate and Vapam on Columbia root-knot nematode and potato yield, 2011. 54th Annual Meeting of the Society of Nematologist, Lansing, Michigan, July 19-24, 2015. Saad L. Hafez, C. Sevy and P. Sandararaj. Effect of Movento alone or in combinations with other nematicides on Meoidogyne chitwoodi and Heterodera schachtii on sugar beet. 54th Annual Meeting of the Society of Nematologist, Lansing, Michigan, July 19-24, 2015. Saad L. Hafez and C. Sevy. New chemistries and compounds for nematode management in potatoes. 54th Annual Meeting of the Society of Nematologist, Lansing, Michigan, July 19-24, 2015.  Xiang, N., and K.S. Lawrence. 2015. Biological potential of Bacillus spp. to reduce the populations of Heterodera glycines and promote plant growth in soybean. 2015 Southern Division - American Phytopathological Society. Phytopathology. 105(Suppl. 2):S2.12-13.<a href="http://apsjournals.apsnet.org/doi/pdf/10.1094/PHYTO-105-4-S2.1">http://apsjournals.apsnet.org/doi/pdf/10.1094/PHYTO-105-4-S2.1</a> Xiang, N., K.S. Lawrence, J.W. Kloepper, and J.A. McInroy. 2015. Plant growth promotion of PGPR on soybean and cotton with and without Heterodera glycines or Meloidogyne incognita. 2015. APS Annual Meeting. Phytopathology 105:(In press). Xiang, N., K.S. Lawrence, J. W. Kloepper, and J. A. McInroy. 2015. Biological control and plant growth promotion of Bacillus spp. on Heterodera glycines in Soybean. 2015 10th International PGPR Workshop. In press.    Proceedings: Land, C. J., K. S. Lawrence, B. Meyer, C. H. Burmester. 2015. Applied Management Strategies for Verticillium Wilt and On-Farm Cotton Cultivar Variety Evaluations. 2014. Proceedings of the Beltwide Cotton Conference, (In Press). National Cotton Council of America, Memphis, TN. http://www.cotton.org/beltwide/proceedings/2005-2012/index.html Land, C. J., K. S. Lawrence, P. Cobine, G. Lawrence. 2015. Tiger Striping Symptoms Caused by Rotylenchulus reniformis in Upland Cotton. 2014. Proceedings of the Beltwide Cotton Conference, (In Press). National Cotton Council of America, Memphis, TN. <a href="http://www.cotton.org/beltwide/proceedings/2005-2012/index.html">http://www.cotton.org/beltwide/proceedings/2005-2012/index.html</a> Land, Caroline, K. S. Lawrence, C. H. Burmester, and B. Meyer. 2015. Applied management options to enhance crop safety against Verticillium wilt. Proceedings of the 8th International IPM Symposium, Salt Lake City, UT, March 5-7, 2015: Vol. 1:74-75. <a href="http://ipmcenters.org/ipmsymposium15/Documents/IPM_2015_Proceedings-final.pdf">http://ipmcenters.org/ipmsymposium15/Documents/IPM_2015_Proceedings-final.pdf</a> Lawrence, K., M. Olsen, T. Faske, R. Hutmacher, J. Muller, J. Mario, R. Kemerait, C. Overstreet, P. Price, G. Sciumbato, G. Lawrence, S. Atwell, S. Thomas, S. Koenning, R. Boman, H. Young, J. Woodward, and H. Mehl. 2015. Cotton disease loss estimate committee report, 2014. Proceedings of the 2014 Beltwide Cotton Conference Vol. 1: 188-190. National Cotton Council of America, Memphis, TN. <a href="http://www.cotton.org/beltwide/proceedings">http://www.cotton.org/beltwide/proceedings</a> Lawrence, K., P. Huang, G. Lawrence,T. Faske, C. Overstreet, T. Wheeler, H. Young, R. Kemerait, and H. Mehl. 2015. Beltwide Nematode Research and Edication Committee 2014 Nematode Research Report. Cotton varietal and nematicide responses in nematode soils. Cotton disease loss estimate committee report, 2014. Proceedings of the 2014 Beltwide Cotton Conference Vol. 1: 739-742. National Cotton Council of America, Memphis, TN. <a href="http://www.cotton.org/beltwide/proceedings">http://www.cotton.org/beltwide/proceedings</a> Lawrence, K. S. and G. W. Lawrence. 2015. A new fungicide, insecticide, nematicide combination for nematode management in cotton. Proceedings of the 8th International IPM Symposium, Salt Lake City, UT, March 5-7, 2015: Vol. 1:72-73. <a href="http://ipmcenters.org/ipmsymposium15/Documents/IPM_2015_Proceedings-final.pdf">http://ipmcenters.org/ipmsymposium15/Documents/IPM_2015_Proceedings-final.pdf</a> Luangkhot, J. A., K.S. Lawrence, C. Land, K. Glass. 2015. Potential Nematicide Yield Benefit and Reniform Yield Reduction to Selected Cotton Cultivars. Proceedings of the 2015 Beltwide Cotton Conferences, San Antonio, TX, January 5-7, 2015: In Press. National Cotton Council of America, Memphis, TN. <a href="http://www.cotton.org/beltwide/proceedings">http://www.cotton.org/beltwide/proceedings</a> Robbins, R. T., B. Fallen, G. Shannon, P. Chen, S. K. Kantartza, T.R. Faske, L.E. Jackson, E.E. Gbur, D.G. Dombek, J.T. Velie, and P. Arelli. 2015. Reniform nematode reproduction on soybean cultivars and breeding lines in 2014.  Proceeding of the 2015 Beltwide Cotton Conferences, San Antonia, TX.  Jan 6-7. Pgs. 201-214. Shankar R. Pant, Brant T. McNeece, Keshav Sharma, Prakash M. Nirula, Jian Jiang, Gary W. Lawrence & Vincent P. Klink (2015) THa development of a plant transformation system for high throughput genomics in Gossypium hirsutum to study root–organism interactions.Proceedings of the Beltwide Cotton Conferences. January 5-7, 2015 San Antonio, Texas   Smith, A. L., K. S. Lawrence, K. Glass, and E. van Santen. 2015. Evaluation of Fusarium wilt resistance in cotton cultivars and identification of pathogenic races of Fusarium oxysporum f. sp. vasinfectum in Alabama. Proceedings of the 2015 Beltwide Cotton Conferences, San Antonio, TX, January 5-7, 2015: In Press. National Cotton Council of America, Memphis, TN. <a href="http://www.cotton.org/beltwide/proceedings">http://www.cotton.org/beltwide/proceedings</a>  Smith, Amber L., K. S. Lawrence, K. Glass, and D. Van Santen. 2015. Management of fusarium wilt in upland cotton of the southeastern United States. Proceedings of the 8th International IPM Symposium, Salt Lake City, UT, March 5-7, 2015: Vol. 1:75. <a href="http://ipmcenters.org/ipmsymposium15/Documents/IPM_2015_Proceedings-final.pdf">http://ipmcenters.org/ipmsymposium15/Documents/IPM_2015_Proceedings-final.pdf</a> Zbylut, J., L. Murray, S.H. Thomas, J. Beacham, J. Schroeder, C. Fiore. 2015.  Modeling ratios with potential zero-inflation to assess soil nematode community structure.  Proceeding of the 25th Annual Kansas State University Conference on Applied Statistics in Agriculture: 130-148.   Extension publications: Cassida, K., Melakeberhan, H., Robertson, P. and Snapp, S. 2015. No matter how you slice it, healthy soil is important. Michigan State University, AgBioResearch Features. <a href="http://agbioresearch.msu.edu/news/no_matter_how_you_slice_it_healthy_soil_is_important?utm_source=MSU+AgBioResearch+E-Newsletter&utm_campaign=d2b52059b8-Futures_Spring_Summer_2015&utm_medium=email&utm_term=0_766437723c-d2b52059b8-230134969">http://agbioresearch.msu.edu/news/no_matter_how_you_slice_it_healthy_soil_is_important?utm_source=MSU+AgBioResearch+E-Newsletter&utm_campaign=d2b52059b8-Futures_Spring_Summer_2015&utm_medium=email&utm_term=0_766437723c-d2b52059b8-230134969</a>. Posted on July 26, 2105. Lawrence, K. S., C. D. Monks, and D. Delaney. Eds. 2015 AU Crops: Cotton Research Report. March 2014. Alabama Agricultural Experiment Station Research Report Series No. 44. <a href="file:///F:/2011%20Passport/AU%20Crops%20report/AU%20Crops%20cotton%20%20report%202015/Cotton%20Bulletin%202015.pdf">file:///F:/2011%20Passport/AU%20Crops%20report/AU%20Crops%20cotton%20%20report%202015/Cotton%20Bulletin%202015.pdf</a> Land, C.J., K. S. Lawrence, C. H. Burmester, and C. Norris. 2015. Bayer CropScience experimental Nematicides for Management of the Reniform Nematode in North Alabama, 2014. Report9:N014 DOI:11.1094/PDMR09. The American Phytopathological Society, St. Paul, MN. Lawrence, K., C. Land, R. Sikkens, C. H. Burmester; C. Norris. Cotton nematicide combinations for reniform management in north Alabama, 2014. Report9:N002 DOI:11.1094/PDMR09. The American Phytopathological Society, St. Paul, MN. Lawrence, K., C. Land, R. Sikkens. Cotton variety and nematicide combinations for root knot management in central Alabama, 2014. Report9:N003 DOI:11.1094/PDMR09. The American Phytopathological Society, St. Paul, MN. Lawrence, K., C. Land, R. Sikkens, C. H. Burmester; C. Norris. Cotton variety and nematicide combinations for root-knot management in central Alabama, 2014. Report9:N004 DOI:11.1094/PDMR09. The American Phytopathological Society, St. Paul, MN. Land, C.J., K. S. Lawrence, B. Miller. 2015. Experimental ReSet for management of the Root-knot on Cucumber, 2014. Report9: N012 DOI:11.1094/PDMR09. The American Phytopathological Society, St. Paul, MN. Land, C.J., K. S. Lawrence, C. H. Burmester, and B. Meyer. 2015. Verticillium Wilt on-farm Cotton Cultivar Variety Evaluations, 2014. Report9: FC098 DOI:11.1094/PDMR09. The American Phytopathological Society, St. Paul, MN. Land, C.J., K. S. Lawrence, C. H. Burmester, and C. Norris. 2015. Experimental Propulse and its efficacy on the Reniform Nematode in North Alabama, 2014. Report9: N011 DOI:11.1094/PDMR09. The American Phytopathological Society, St. Paul, MN. Saad L. Hafez and Mahesh P. Pudasaini, 2015. Efficacy of Movento alone or in combinations with other compounds in drip irrigation system for the management of onion nematodes, 2013. Plant Disease management report, Vol. 9. Saad L. Hafez and Mahesh P. Pudasaini, 2015. Effect of Movento alone of in combinations with Vydate or Vapam for control of Columbia root-knot nematode in Potato, 2012. Plant Disease management report, Vol 9. Saad L. Hafez and Mahesh P. Pudasaini. 2015. Optimum timing of Movento application for control of Columbia root-knot nematode in Potato, 2012. Plant Disease management report, Vol 9. Saad L. Hafez and P. Sundararaj. 2015. Effect of Vapam alone or with Adsorb on Columbia root-knot nematode and potato yield, 2011. Plant Disease management report, Vol 9. Saad L. Hafez and P. Sundararaj. 2015. Efficacy of Telone II for the control of Columbia root-knot nematode on potato, 2010. Plant Disease management report, Vol 9. Saad L. Hafez and P. Sundararaj. 2015. Effect of Movento alone or in combinations with Vydate and Vapm on Columbia root-knot nematode and potato yield, 2011. Plant Disease management report, Vol 9. Saad L. Hafez and P. Sundararaj. 2015. Effect of different chemicals for the management of Columbia root-knot nematode on potato, 2011. Plant Disease management report, Vol 9. Saad L. Hafez and P. Sundararaj. 2015. Effect of MCW on Columbia root-knot nematode and potato yield, 2011. Plant Disease management report, Vol 9. Saad L. Hafez and P. Sundararaj. 2015. Effect of MCW-2 on Columbia root-knot nematode and potato yield, 2011. Plant Disease management report, Vol 9. Saad L. Hafez and P. Sundararaj. 2015. Effect of MCW-2 formulations at different rates on potato and root lesion nematode under greenhouse conditions, 2011. Plant Disease management report, Vol 9. Saad L. Hafez and P. Sundararaj. 2015.Effect of MCW-2 alone or in combination with Vydate on Tobacco rattle virus and potato yield, 2011. Plant Disease management report, Vol 9. Saad L. Hafez and P. Sundararaj. 2015. Evaluation of new chemicals for the management of Columbia root-knot nematode on potato, 2010. Plant Disease management report, Vol 9.

Impact Statements

Tubers from both yellow nutsedge and purple nutsedge provide a consistent reservoir of Meloidogyne incognita to infect subsequent crops irrespective of previous crop in New Mexico.

Date of Annual Report: 01/19/2017

Report Information

Annual Meeting Dates: 11/10/2016 - 11/11/2016
Period the Report Covers: 10/01/2015 - 09/30/2016

Participants

Caswell-Chen, Ed (epcaswell@ucdavis.edu) - University of California Davis;
Gleason, Cynthia (cynthia.gleason@wsu.edu) - Washington State University;
Hafez, Saad (shafez@uidaho.edu) – Univeristy of Idaho;
Ingham, Russell (inghamr@science.oregonstate.edu) – Oregon State University;
Lawrence, Gary (glawrence@entomology.msstate.edu) – Mississippi State University;
Lawrence, Kathy (lawrekk@auburn.edu) – Auburn University;
Melakeberhan, Haddish (melakebe@anr.msu.edu) – Michigan State University;
Powers, Thomas (tpowers1@unl.edu) – University of Nebraska;
Robbins, Robert (rrobbin@uark.edu) – University of Arkansas;
Roberts, Philip (philip.roberts@ucr.edu) – University of California,
Riverside; Sipes, Brent (sipes@hawaii.edu) – University of Hawaii;
Klink, Vincent (vklink@biology.msstate.edu) – Mississippi State University;
Thomas, Steve (stthomas@nmsu.edu) - New Mexico State University

Brief Summary of Minutes

Minutes Attachment:

W3186andS1066Minutes2016_Edited.docx.pdf

Accomplishments

Objective 1:   Characterize genetic and biological variation in nematodes relevant to crop production and trade.  Molecular identification of nematodes is very important. DNA barcoding has been applied to four major groups of plant-parasitic nematodes. A barcoding survey of Pratylenchus populations primarily associated with corn, wheat, and soybeans was conducted with soil samples from ten central and western U.S. states and Canada. Six clades or haplotype groups were recognized by mitochondrial markers. In greenhouse house tests, the haplotype groups displayed differential reproduction on a set of hosts that included corn, wheat, soybeans, and sorghum. DNA barcoding of nematodes extracted from forage seed and rice was examined for the presence of Aphelenchoides besseyi, the nematode species responsible for white tip of rice disease. Using genetic markers for mitochondrial DNA, it was determined that forage seed from South America was infected by Aphelenchoides fujianensis and not A. besseyi. However, one specimen from forage seed was grouped with a larger clade that included A. besseyi. Species boundaries of A. besseyi are currently compromised due to apparent misidentifications of specimens in GenBank. Corrections need to be made in GenBank in order to more accurately determine species boundaries in Aphelenchoides species. A new mitochondrial primer set has been applied to the major species groups in Meloidogyne. This primer set appears to separate M. javanica, M. incognita, and M. arenaria while recognizing subgroups within the species. Testing of a large panel of Meloidogyne isolates is ongoing. A large scale evaluation of genera and species in the suborder Criconematina has resolved a number of taxonomic issues affecting accurate identification and classification within the group. Relative taxonomic resolution of 18S, COI, and ITS markers has been analyzed using a set of over 1,300 specimens from North America. Ditylenchus dispsaci was encountered for the first time in NM in a small acreage of non-commercial garlic Exotic populations of Ditylenchus species, including D. dipsaci, D. africanus, D. weischeri, and D. angustus have been tested using a contiguous segment of the rRNA gene spanning the 18S, ITS1, 5.8S, ITS2, and a portion of the 28S regions. These results strengthen our understanding of intra-species genetic variation associated with this ribosomal region in an important, internationally-regulated genus.  Evaluation of deep sequencing methodologies as a platform for identification of nematodes of regulatory importance in agricultural samples employed the Single Molecule Real Time (SMRT) platform for sequencing of PCR amplicons amplified from populations of nematodes extracted from soil samples. The accuracy of the SMRT platform is reported to be proportional to the length of the amplicons sequenced, with shorter amplicons being sequenced with higher accuracy, and that accuracy can drop near or below 90% for longer amplicons (over 10 Kbp) while the reported accuracy is supposed to be greater than 98% for the length of amplicons that we are working with (1.5-4 Kbp).   We performed SMRT sequencing on nematode populations isolated from a golf course and a vineyard.  All samples produced a large amount of single pass sequence, ~100-150K or more reads per sample.  Quality scores on these raw reads were moderate with most reads having an average quality score of ~20 (over 30 is desirable).  After generating circular consensus sequences (error checking via generating a consensus for multiple reads on a single template) we were left with ~30K reads per sample that had an average quality score over 30 suggesting an overall accuracy of 98% or greater.   Each sample had ~10,000 nematodes, estimated by counting of a subsample prior to lysis and PCR, so we anticipate that each nematode was represented ~3 times.  Grouping redundant sequences in the SMRT sequence data suggested that there were ~5K groups present with some being rare (one to a few sequences present) and some being common (many redundant sequences present) which is consistent with the nematode population estimates of a diverse population with some species being common and others being rare.  A quick in silico screen suggests that 90% or more of the sequences are greater than 70% related to the 18S rRNA of M. arenaria.  Taken together, these preliminary results suggest that we were successful in capturing the diversity of the nematodes isolated from the soil samples in the sequence data. Based on results to date we anticipate that it will be relatively simple to convert SMRT sequences generated in this work into searchable databases which can be queried to determine if sequences from nematodes of regulatory concern are present- the next goal for the bioinformatics portion of this project.  Development of simple procedures for turning raw SMRT sequence data into databases of accurate error checked sequences that can be queried for sequences of interest will enable using this technology as a tool for detecting the presence of nematodes of regulatory concern.  Root-knot nematodes, or Meloidogyne spp., are one of the most significant plant-parasitic nematodes found in the United States.  Species identification of Meloidogyne based upon molecular techniques that are much quicker than current standards. Individual nematodes are “smashed” for DNA, PCR (Polymerase Chain Reaction) amplifies the DNA, and gel electrophoresis uses band sizes to identify specific species.  Only Meloidogyne incognita race 3 and M. arenaria race 1 have been identified thus far in Alabama peanut fields. In Michigan vegetable production Pratylenchus (detected in 71% of fields sampled), Meloidogyne (41% of fields), Paratylenchus (26% of fields), and Heterodera (18% of fields). Helicotylenchus, Paratrichodorus, Hoplolaimus, and Xiphinema were detected. Ten populations of M. hapla show differences in reproductive potential.  The nematode community in the vegetable fields was dominated by bacteria-feeding nematodes (67% mean relative abundance) while fungal-feeding (16% relative abundance) and plant-parasitic nematodes (14% relative abundance) constituted most of the rest of the community.  Omnivores and predators (3% relative abundance) represented a small proportion of the nematode community.  This nematode community structure suggests Michigan vegetable fields have resource-rich, but relatively basic soil food webs.  Entomopathogenic nematodes (EPNs) parasitize insects utilizing mutualistic bacteria to infect and kill the host, allowing the nematode to feed and reproduce within the insect cadaver. Consequently EPNs are highly sought after for their biological control potential. A survey for EPNs was conducted on O'ahu and Hawai'i Island using a modified baiting method. One hundred seven soil samples were collected and baited with five Tenebrio molitor (mealworm) larvae. Soil samples were observed daily for 5 days and morbid T. molitor larvae were placed on white traps. Forty-seven of the 107 locations contained at least one infected mealworm containing nematodes. Mealworm mortality was attributed to EPNs, fungi, parasitoids, or unknown factors in 16%, 10%, 1% and 73% of samples respectively. Eighty-two EPN isolates were passed through two subsequent inoculations in order to confirm their entomopathogenic nature. A total of 41 EPN isolates were recovered through three rounds of reinoculation and recovery. PCR analysis and sequencing was conducted on third generation nematodes, targeting the ITS region. Sequencing analysis suggested three groups of Oscheius. Oscheius was recovered from 96% of locations sampled on Hawai'i Island and O'ahu respectively. The Oscheius isolates and an unknown EPN isolate occurred in 76%, 12%, 8% and 4% of positive locations respectively.  This suggests that Oscheius is a common EPN in Hawai'i. Objective 2:  Determine nematode adaptation processes to hosts, agro-ecosystems and environments. Yield losses due to the soybean cyst nematode are increasing and evidence suggests races may have shifted, rendering current crop rotation schemes ineffective. Because the nematode virulence classification is transitioning between the traditional race system and the HG Type system, soybean cyst nematode populations are being evaluated using both systems. Producers unfamiliar with the nematode are being educated with a race distribution map. Turmeric (Curcuma longa), a spice crop native to Southeast Asia, has experienced a dramatic increase in demand due to its anti-inflammatory and other health-promoting properties. Turmeric is undergoing evaluation as a potential cash crop. Meloidogyne spp. negatively affects turmeric production systems, causing significant losses to production each year. Selection for tolerance or resistance to Meloidogyne spp. will be a key factor in establishing successful turmeric production. Mint (Mentha spp.) is a high value crop used worldwide for a variety of purposes. In Idaho and Eastern Oregon, Pratylenchus is common (89% of samples) at population densities ranging from 0-1,940/500 cm3 soil. Paratylenchus was found in 72% of the samples at population densities ranging from 0-195,200/500 cm3 soil.  Stunt and spiral nematodes occur in half of the samples at populations ranging from 0-890 and 0-3,400/500 cm3 soil, respectively.  We do not know if Paratylenchus is pathogenic to mint, interacts with Verticillium wilt, nor do we know appropriate management practices for the nematode in mint. Ditylenchus medicaginis was reported for the first time in the United States. Mint has potential for use as a living mulch in smallholder production systems. Meloidogyne incongnita, M. javanica and Rotylenchulus reniformis are common plant-parasitic nematodes found in tropical climates. Consequently, susceptibility of mint to these nematodes should be considered. A greenhouse test demonstrated that neither spearmint nor peppermint was a host to these nematodes. The nematode reproductive factor was less than 1 for each nematode on both plants. In a field miroplot test, eggplant was intercropped with spearmint as a living mulch. Eggplant yield with spearmint was higher than eggplant in bare ground plots (P <0.05). Eggplant intercropped with mint increased revenue for the farmer by more than 300%.  The selection of landscape plants can have profound impacts on the environment. The susceptibility of 21 perennial plant species recommended for use in xeriscape plantings to Meloidogyne incognita is being determined. Variation in RF values within a species will provide valuable information regarding the possible presence of resistance genes within the host population.  We can modify soil health with different agronomic practices. Cover crops showed soil type-specific soil health outcomes. In a Michigan carrot production soils, nematode community analysis showed few short-term impacts of cover cropping. At one site, enrichment and structure indices were affected by cover crop treatments at carrot harvest. Enrichment index was greater after oats-radish mixture or Dwarf Essex rape than oats alone or fallow control.  Structure index was greater after radish alone or Dwarf Essex rape than oats alone.  At a second site, bacterivore nematode densities were increased by oats or radish cover crops compared to control, but only during carrot production.  Overall, the variable effects of cover crops and other agronomic practices such as tillage and soil nutrient amendment use on soil health strongly point to location-specific application than a one-size-fits-all approach to get the best outcome. Objective 3:  Develop and assess nematode management strategies in agricultural production systems. The addition of inputs such as starter fertilizers, plant growth regulators, and nematicides can provide for a complete management system by improving plant health and suppressing nematode population densities. In a corn and Meloidogyne system, shoot and root fresh weights and biomass were greater in the untreated control (P ≤ 0.1) than with Terbufos and Clothianidin/Bacillus firmus + Fluopyram/Imidacloprid nematicides at 14 days after planting (DAP). However, at 45 DAP the untreated control’s growth parameters were all lower (P ≤ 0.1) than the nematicide treatments. Terbufos, Fluopyram/Imidacloprid, and Clothianidin/Bacillus firmus + Fluopyram/Imidacloprid all reduced root knot egg production (P ≤ 0.1), and Terbufos increased biomass (P ≤ 0.1) relative to the untreated control. In the plant growth regulator trial, Ascend (0.090% cytokinin: 0.030% gibberellic acid: 0.045% indolebutyric acid) was the product selected and the efficacy of single to multiple applications were evaluated. At 45 DAP, the in-furrow application (365 ml/ha rate) improved plant growth parameters (shoot/root fresh weight and biomass) (P ≤ 0.1) relative to the untreated control, and was similar to the untreated control in eggs per gram of root. The triple combination (in-furrow + foliar + seed treatment) supported increased numbers of root knot eggs per gram of root (P ≤ 0.1) relative to the untreated control. The starter fertilizer treatments all increased plant biomass (P ≤ 0.1) relative to the untreated control at 45 DAP with the exception of Micro-500 and Neptune’s Harvest. From the greenhouse tests, we selected nematicides Terbufos and Fluopyram, the plant growth regulator’s in-furrow application, and the combination of starter fertilizers (Pro-Germinator + Sure-K + Micro 500) to be further evaluated in field and microplot settings to determine yield effects. In a soybean and Meloidogyne system, resistant cultivars and nematicides are two proscribed methods of control and yield loss prevention for these plant parasitic nematodes. This study screened susceptible, moderate resistant and resistant varieties in the presence and absence of the nematicide Avicta (Abamectin) in order to determine the efficacy of the nematicide seed treatment to prevent biomass and yield reduction caused by this phytopathogenic nematode. Ten soybean varieties were evaluated: one root-knot (RKN) susceptible, four moderate resistant, and five resistant varieties. The experiment used three factor tests, each having replicates of all varieties. The test groups were: Control (no RKN, no nematicide treatment), Variety (RKN inoculated, no nematicide treatment), and Nematicide (RKN inoculated, nematicide treated seed). Nematicide treated seeds received 0.15 mg Abamectin per seed. Greenhouse trials were conducted in 150cc cone-tainers in a RCBD with 5 replicates per treatment. Treatments to include RKN were inoculated with 2,000 Meloidogyne incognita eggs at planting. Plant height, fresh shoot and root weights were recorded at 45 days after planting. Greenhouse trials were repeated and data analyzed in SAS 9.4 by Tukey’s (P ≤ 0.05), comparing means across varieties and tests. The nematicide seed treatment Abamectin increased plant biomass by 5% on average (P ≤ 0.05) in the presence of M. incognita. Root fresh weight was also increased 17 % with the nematicide application Abamectin decreased M. incognita eggs per gram of root by 77%; the nematicide treatment significantly reduced nematode egg densities across all varieties. Additionally, Abamectin increased biomass in resistant, moderately resistant and susceptible varieties similarly. Abamectin decreased eggs per gram in the susceptible variety by 84%, 75% on moderate varieties on average, and by 77% in resistant varieties on average. Additionally, Abamectin increased plant biomass by 10%, 1%, and 5% on average in susceptible, moderately resistant, and resistant varieties respectively. This test will be conducted in field trials in the 2016 season to determine if the increase in plant biomass translates into increased yield in varieties treated with a nematicide. Breeding variates of soybean have been evaluated for resistance to reniform nematode, and several lines have been identified that have resistance. Work is underway to identify these resistant genes. Rotylenchulus reniformis was previously controlled using at-planting treatments of Temik 15G or soil fumigants. With Temik 15G being removed from the market and fumigant expenses rising, Nematicide Seed Treatment (NST) with and without foliar applications of Vydate-CLV® has become an alternative.     All NSTs improved root and shoot biomass of cotton.  Aeris® + Votivo® produced greater biomass in inoculated populations (Pi) up to 5,000 reniform nematodes/500 cc of soil comparable to Temik 15G.  Temik 15 G did continue providing growth at higher R. reniformis populations. Aeris was reduced in bimoss earlier than other treatments at 2,500 reniform nematodes/500 cc.   In-field plant mapping indicated node of first fruiting branch (NFFB) reduced with all nematicides while plant height and height to node ratios (HNR) were greater with Vydate-CLV®. At the final mapping evaluation, Vydate-CLV® improved retention at position two and greater.  In a cotton and reniform nematode system, nematicides were used to demonstrate yield reduction. R. reniformis reduced yield by an average of 39% across 10 different cultivars ranging from 26-45% reduction. Velum Total increased yield by an average of 5%, and reduced egg production per gram of root by an average of 67% across 10 cultivars.  In mint, lesion and pin nematode can occur with Verticillium wilt fungus. No current or new treatment was effective in reducing pin nematode populations or slowing or stopping Verticillium wilt infections. Mint plants were heavily damaged by Verticillium wilt in the greenhouse trials. Lesion nematode + Verticillium wilt had more extreme damage than pin nematode alone and pin nematode + Verticillium wilt. On-going are efforts to integrated soil food web functions to the fertilizer use efficiency (FUE) model, which separates nutrient deficiency and toxicity from nematode (pest) suppression and agro-ecological efficiency. Ongoing studies of management of injury to bentgrass greens at NM golf courses resulting from high populations of Mesocriconema spp., Pratylenchus spp., and Longidorus breviannulatus showed continued efficacy Avid® (2% abamectin) when applied at maximum recommended rates for suppression of Mesocriconema spp and Longidorus breviannulatus. However, populations of continue to increase and show little response to treatment.  Subsequent applications of Nimitz® Pro G (fluensulfone 1.5%) suppressed Pratylenchus populations by 50%, with Pratylenchus numbers still exceeding the damage threshold in 60% of greens, while producing mild discoloration of turf.  Preplant soil samples preceding pinto bean revealed 78% of the 64 fields surveyed contained Pratylenchus populations that exceeded the damage threshold of 50 nematodes per 100 cm3 soil – some by as much as 12-fold.  A microplot study was initiated to determine the response of pinto bean and associated plant-parasitic nematode populations to different rates of Nimitz® but the study was lost due to rodent predation, and will be repeated in 2017. Columbia Root-knot Nematodes (CRKN, Meloidogyne chitwoodi) infect potato tubers and cause quality defects consisting of galling of the tuber surface and small brown spots that surround the female and egg mass inside the tuber. There is little tolerance for infection in tubers in domestic markets for fresh or processed potatoes and crops which exceed these tolerances may be devalued or rejected. Furthermore, there is no tolerance for infection in tubers intended for export to countries where CRKN is considered a quarantined pest and even one infested tuber can prevent a shipment from being exported. The primary method used for control of CRKN is with soil fumigant (Telone II, metam sodium) and nonfumigant (Mocap, Vydate) nematicides. However, an inadequate supply of the ingredients used to manufacture Telone II and increased global demand as resulted in an insufficient supply to meet the needs of potato growers. In addition, there was an accident at the facility the produced Vydate and it is not currently available. This has increased the demand for Telone which is already in short supply. Health and environmental concerns have led to the formation of buffer zones that often restrict the area of a field that can be treated with metam sodium. In addition, growers are becoming increasingly interested in biological approaches to nematode management. We are investigating different strategies that may reduce reproduction by CRKN that could either result in sufficient control alone or reduce population densities to a level that could then be controlled by reduced rates of products that are in short supply. Biological strategies that we have hypothesized may be promising include: Grow poor or non-host crops as 1) Cash crops, 2) Cover crops, 3) Incorporate green manure crops (biofumigation), 4) Apply biocontrol products early in season, and 5) Combine these strategies. Winter wheat cv Stephens, barley (cv C-69) and Sudangrass (cv Sordan 79) had Rf of 21.62, 11.54 and 0.02, respectively. While population densities of CRKN increased substantially on wheat and barley, the declined to very low levels in pots planted to ‘Sordan 79’ sudangrass. Amendment with wheat cv Stephens or sudan cv Sordan 79 fresh resulted in Rfs of 9.84, 6.20, 6.43, 5.06 and 0.85 for unamended pots and pots amended with wheat at 15 Tons/acre, wheat at 39 Tons/acre, sudangrass at 15, and sudangrass at 39 Tons/acre, respectively. Addition of shoot biomass appeared to have a greater effect on J2 in the soil than eggs on the roots. Amending soil with wheat or sudangrass shoot biomass markedly suppressed J2 densities. However, only the high rate of wheat amendment was significant whereas both rates of sudangrass had significantly fewer J2 than in unamended pots. Neither rate of wheat biomass reduced numbers of eggs or Rf. Both rates of sudangrass amendment reduced reproduction (Rf) compared to unamended soil, but only the high rate suppressed egg production to below the number added at the beginning. Effectors, phytohormones, nematode secretions, and jasmonic acid are being investigate as potential avenues for control as well. Mc RMc1(blb) gene to be used to study virulence and avirulence in M. chitwoodi. One strategy for nematode management is the application of biological control products. Several biological products are being applied to growers’ fields that may have an effect on nematodes although they may not be marketed as nematicides. Very few have been tested. The following products were tested and were applied as recommended by the product representatives. Bio Blend is distributed by Soil Guys (San Luis Valley, CO) and contains Agrothrive fermented fish product, Soil Medic, Sobec, and Soyaplex in a proprietary blend. Hyper Galaxy is sold by Holmes Enviro, LLC (Philomath, OR) as a consortia of plant growth-promoting rhizobacteria (PGPR) for early crop growth. Specific bacteria include: Azospirillum brazilense, Azotobacter chroococcum, Bacillus azotofixans, Pseudomonas fluorescens, and Pseudomonas putida. MeloCon consists of Paecilomyces lilacinus strain 251, a fungal parasite of nematode eggs that is marketed by Certis as a biological nematicide. Reproduction on wheat cv Stephens was 4.71, 1.71, 1.49 and 0.40 for untreated pots, and pots treated with Bio Blend, Hyper Galaxy, and MeloCon, respectively. All treatments except Hyper Galaxy had significantly fewer CRKN J2 in the soil than in the nontreated control. There were no differences between products. All treatments had fewer eggs than on nontreated plants. MeloCon had fewer eggs than Bio Blend. All treatments suppressed reproduction compared to that in nontreated plants. MeloCon suppressed reproduction more than Bio Blend or Hyper Galaxy. At the end of the study there were fewer CRKN in the MeloCon treatment than at the beginning. To manage Rotylenchulus reniformis on cotton and soybean, seeds treated with the Abamectin, ILeVo, and a non-treated control have been evaluated. On cotton, seeds treated with Abamectin and ALB-G304+ALB-M305-1 (7+ 3 fl. oz/cwt) significantly reduced the numbers of R. reniformis eggs recovered from the cotton roots. Seeds treated with Abamectin and ALB-M305-3 (10 fl. oz/cwt) had fewer juveniles vermiform adults recovered from the soil compared with the non-treated seeds. On soybean, seeds treated with Abmectin and ALB-BE3 + ALB-SAR 2 (7+ 0.25 fl. oz/cwt) significantly reduced the number of eggs recovered compared with the non-treated control. Abamectin, ALB SAR (0.01 fl.oz/cwt), ALB-BE3 + ALB-SAR 2(7+ 0.25 fl.oz/cwt) and ALB-M305-1(7 fl.oz/cwt) significantly reduced the number of vermiform life stages that were found in the soil compared with the non-treatment. No negative effects were recorded on plant growth.

Publications

Book Chapter Nyaku, S.T., Tilahun, Y., Lawrence, K., Sripathi, V.R., Williams, A.J., and Sharma, G.C. 2016. Genetic resistance to the reniform nematode in cotton. In: Cotton Research. ed by I.Y. Abdurakhmonov. DOI: 10.5772/64389 Journal Articles French, J.M.,Beacham, J., Garcia, A., Goldberg, N.P., Thomas, S.H., and Hanson, S.F. 2016.  First report of stem and bulb nematode Ditylenchus dipsaci on garlic in New Mexico.  Plant Health Progress (submitted). Grabau, Z.J., B.P. Werling, R. Goldy, B. Phillips, and H. Melakeberhan. 2016. Plant parasitic nematode distribution in Michigan vegetable soils. <a href="http://msue.anr.msu.edu/news/plant_parasitic_and_beneficial%20_nematode_distribution.">http://msue.anr.msu.edu/news/plant_parasitic_and_beneficial _nematode_distribution.</a> Klink, V.P. 2016. Plastic embedding tissue for laser microdissection-assisted developmental genomics analyses at single cell resolution. Medical Research Archives 4:1-12. Land, C.J., Lawrence, K.S., and Newman, M. 2016. First report of Verticillium dahliae on cotton in Alabama. Plant Dis. 100:1, 2016; published online as <a href="http://dx.doi.org/10.1094/PDIS-10-15-1143-PDN">http://dx.doi.org/10.1094/PDIS-10-15-1143-PDN</a>. Meyers, R.Y., Sipes, B.S., Matsumoto, T.K., Mello, C.L., and Mello, J.S. 2015. Distribution of Heterorhabditid populations in Hawaii. Nematropica 45:198-207. Pant, S.R., McNeece, B.T., Sharma, K., Nirula, P.M., Burson, H.E., Lawrence, G.W., and Klink, V.P. 2016. The heterologous expression of a Glycine max homolog of NONEXPRESSOR OF PR1 (NPR1) and a-hydroxynitrile glucosidase suppresses parasitism by the root pathogen Meloidogyne incognita in Gossypium hirsutum. Journal of Plant Interactions 11:41-52. Powers, T.O., Bernard, E.C., Harris, T., Higgins, R., Olson, M., Olson, S., Lodema, M., Matczyszyn, J., Mullin, P., Sutton, L., and Powers. K.S. 2016. Species discovery and diversity in Lobocriconema (Criconematidae: Nematoda) and related plant-parasitic nematodes from North American ecoregions. Zootaxa 4085 (3): 301–344. <a href="http://doi.org/10.11646/zootaxa.4085.3.1">http://doi.org/10.11646/zootaxa.4085.3.1</a> Powers, T.O., Mullin, P., Higgins, R., Harris, T., and Powers, K.S. 2016. Description of Mesocriconema ericaceum n. sp. (Nematoda: Criconematidae) and notes on other nematode species discovered in an ericaceous heath bald community in Great Smoky Mountains National Park, USA. Nematology (Available online: 14 June 2016) <a href="http://dx.doi.org/10.1163/15685411-00003001">http://dx.doi.org/10.1163/15685411-00003001</a> Pradhan, A., Chan, C., Roul, P.K., Halbrendt, J., and Sipes, B. 2016. Potential of conservation agriculture (CA) as climate smart technology for food security under rainfed uplands of India: A transdisciplinary approach. Agricultural Systems 149: in press. Sharma, K., Pant, S.R., McNeece, B.T., Nirula, P.M., Burson, H.E., Lawrence, G.W., and Klink, V.P. 2016. Co-regulation of the Glycine max soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor (SNARE)-containing regulon occurs during defense to a root pathogen. Journal of Plant Interactions 11:74-93. Yu, Q., Ye, W. & Powers, T. 2016. Morphological and molecular characterization of Gracilacus wuae n. sp. (Nematoda: Criconematoidea) associated with cow parsnip (Heracleum maximum) in Ontario, Canada. Journal of Nematology (Accepted for Publication 3 August 2016 ) Xiang, N. and Lawrence, K.S. 2016. Optimization of in vitro techniques for distinguishing between live and dead second stage juveniles of Heterodera glycines and Meloidogyne incognita. PLOS ONE: http://dx.doi.org/10.1371/journal.pone.0154818 Published Abstracts Bisel, J., Myers, R., and Sipes, B. 2016. Endemic Oscheius nematodes of Hawaii. Journal of Nematology 47: in press. Chan, K.D., Sipes, B., Wang, K.H., and Leung, P.S. 2016. Mentha spicata: A potential living mulch for conservation agricultural practices in tropical climates. Journal of Nematology 47: in press. Dodge, D., and K. Lawrence. 2016. Combination effect of commercial starter fertilizers, plant hormones and nematicides on soybean growth and pest management of Meloidogyne incognita. Proceedings of the 2016 Beltwide Conference Vol. 1: 577-580. National Cotton Council of America, Memphis, TN. <a href="http://www.cotton.org/beltwide/proceedings/2005-2016/index.htm">http://www.cotton.org/beltwide/proceedings/2005-2016/index.htm</a> Dodge, D., and K. S. Lawrence. 2016. Soybean variety yield comparison with and without Velum Total for management of root-knot nematode Alabama, 2015. Report No. 10:N007. DOI: 11.1094/PDMR10. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/n007.asp">http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/n007.asp</a> Dodge, D., and K. S. Lawrence. 2016. Nematicide and fungicide efficacy and yield comparison for management of root-knot nematode on soybean Alabama, 2015. Report No. 10:N008. DOI: 11.1094/PDMR10. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/n008.asp">http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/n008.asp</a> Grabau, Z.J., Z.T.Z. Maung, C. Noyes, D. Baas, B.P. Werling, D.C. Brainard, and H. Melakeberhan. 2016. Short-term effects of cover cropping on root-lesion nematode, stunt nematode and soil ecology in Michigan carrot production. Joint Meeting of the Society of Nematologists and Organization of Tropical America Nematologists Program Abstracts. 94. Grabau, Z.J., Z.T.Z. Maung, C. Noyes, D. Baas, B.P. Werling, D.C. Brainard, and H. Melakeberhan. 2016. Cover cropping affects plant-parasitic and free-living nematodes in Michigan carrot production. American Phytopathological Society Annual Meeting Program Abstracts. 0000. Grabau, Z.J., B.P. Werling, and H. Melakeberhan. 2016. Plant-parasitic nematodes and nematode community composition in selected Michigan vegetable fields. Joint Meeting of the Society of Nematologists and Organization of Tropical America Nematologists Program Abstracts. 95. Groover, W., and K. Lawrence. 2016. Diagnostic identification of Meloidogyne species to expedite pathogen detection in row crops. Proceedings of the 2016 Beltwide Conference Vol. 1: 574-576. National Cotton Council of America, Memphis, TN. <a href="http://www.cotton.org/beltwide/proceedings/2005-2016/index.htm">http://www.cotton.org/beltwide/proceedings/2005-2016/index.htm</a> Hafez, S.L. 2016. New compounds and chemistries for controlling nematodes, 2015-2016. 48th Annual Meeting of the Organization of Nematologoists of Tropical America and 55th Annual meeting of the Society of Nematologists, Montreal, Canada. Hafez, S.L. and Sundararaj, P. 2016. Chemical management practices for the management of Meloidogyne chitwoodii on potato in Idaho, USA. 48th Annual Meeting of the Organization of Nematologoists of Tropical America and 55th Annual meeting of the Society of Nematologists, Montreal, Canada. Hafez, S.L. and Sevy, C. 2016. Lesion nematode and Verticillium wilt interactions in greenhouse mint. 48th Annual Meeting of the Organization of Nematologoists of Tropical America and 55th Annual meeting of the Society of Nematologists, Montreal, Canada. Ingham, R.E., W.S. Phillips, A. Peetz, N.M. Wade, and I.A. Zasada. 2015. Effects of the cyst nematode Globodera ellingtonae on potato.  Journal of Nematology 47:247. Kalaiselvi, D., Rajanandhini, M., Sundararaj, P., Hafez, S., and Sundararaj, N. 2016. Promising approach for improving the effect of silver nanoparticle applications in soil for Meloidogyne incognita management: synthesis and application. 48th Annual Meeting of the Organization of Nematologoists of Tropical America and 55th Annual meeting of the Society of Nematologists, Montreal, Canada. Lawrence, K., A. Hagan, M. Olsen, T. Faske, R. Hutmacher, J. Mueller, D. Wright, R. Kemerait, C. Overstreet, P. Price, G. Lawrence, T. Allen, S. Atwell, S. Thomas, N. Goldberg, K. Edmisten, R. Bowman, H. Young, J. Woodward,and H. Mehl. 2016. Cotton disease loss estimate committee report, 2015. Proceedings of the 2016 Beltwide Cotton Conference Vol. 1: 113-115. National Cotton Council of America, Memphis, TN. <a href="http://www.cotton.org/beltwide/proceedings/2005-2016/index.htm">http://www.cotton.org/beltwide/proceedings/2005-2016/index.htm</a> Lawrence, K. S., C. J. Land, N. Xiang, J. Luangkhot, and C. Norris. 2016. Fungicide combination evaluations for cotton seedling disease management in north Alabama, 2015. Report No. 10:FC012. DOI: 11.1094/PDMR10. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/fc012.asp">http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/fc012.asp</a> Lawrence, K. S., C. J. Land, N. Xiang, and J. Luangkhot. 2016. Cotton variety and nematicide combinations for root-knot nematode management in Alabama, 2015. Report No. 10:FC133. DOI: 11.1094/PDMR10. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/fc133.asp">http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/fc133.asp</a> Lawrence, K. S., C. J. Land, N. Xiang, J. Luangkhot, and C. Norris. 2016. Cotton variety and nematicide combinations for reniform management in north Alabama, 2015. Report No. 10:N010. DOI: 11.1094/PDMR10. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/n010.asp">http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/n010.asp</a> Lawrence, K. S., C. J. Land, N. Xiang, J. Luangkhot, and C. Norris. 2016. Velum Total in-furrow spray applications for reniform management in north Alabama, 2015. Report No. 10:N011. DOI: 11.1094/PDMR10. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/n011.asp">http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/n011.asp</a> Lawrence, K. S., C. J. Land, N. Xiang, J. Luangkhot, and C. Norris. 2016. Vydate CLV in-furrow spray applications for reniform management in north Alabama, 2015. Report No. 10:N012. DOI: 11.1094/PDMR10. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/n012.asp">http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/n012.asp</a> Lawrence, K., G. Lawrence, T. Faske, R. Kemerait, C. Overstreet, T. Wheeler, H. Young, and H. Mehl. 2016. Beltwide nematode research and education committee 2015 nematode research report cotton varietal and nematicide responses in nematode soils. Proceedings of the 2016 Beltwide Conference Vol 1: 737-740. National Cotton Council of America, Memphis, TN. <a href="http://www.cotton.org/beltwide/proceedings/2005-2016/index.htm">http://www.cotton.org/beltwide/proceedings/2005-2016/index.htm</a> Luangkhot, J, and K. Lawrence. 2016. Growth hormone and starter fertilizer effects on root-knot population suppression and cotton yield enhancement when combined with Velum total or Vydate CLV. Proceedings of the 2016 Beltwide Conference Vol 1: 719-727. National Cotton Council of America, Memphis, TN. <a href="http://www.cotton.org/beltwide/proceedings/2005-2016/index.htm">http://www.cotton.org/beltwide/proceedings/2005-2016/index.htm</a> Luangkhot, J., and K. S. Lawrence. 2016. Reniform nematode management utilizing variety selection with and without seed treatments in Alabama, 2015. Report No. 10:N001. DOI: 11.1094/PDMR10. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/n001.asp">http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/n001.asp</a> Luangkhot, J., and K. S. Lawrence. 2016. In-furrow sprays on cotton to manage Southern root-knot nematode in Alabama, 2015. Report No. 10:N002. DOI: 11.1094/PDMR10. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/n002.asp">http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/n002.asp</a> Mohankumar, A., Shanmugam, G., Sundararaj, P., Hafez, S., and Sundararaj, N. 2016. Phloroglucinol (1,3,5-trihydrocybenzene) enhanced the ameliorates stress resistance and reduced β-amyloid toxicity in Caenorhabditis elegans. 48th Annual Meeting of the Organization of Nematologoists of Tropical America and 55th Annual meeting of the Society of Nematologists, Montreal, Canada. Pradhan, A., Chan, C., Roul, P.K., Halbrendt, J., and Sipes, B. 2016. Potential of conservation agriculture production systems (CAPS) as climate smart technology for food security under rainfed uplands of India: A transdisciplinary approach. International Food and Agribusiness Management Association World Conference, Aarhus, Denmark. Rothrock, C., T. Allen, H. Kelly, R. Kemerait, G. Lawrence, K. Lawrence, H. Mehl, R. Norton, P. Price, and J. Woodward. 2016. Impact of seedling diseases and Pre-emergence herbicides on cotton stand establishment and plant development. Proceedings of the 2016 Beltwide Conference Vol 1: 741-742. National Cotton Council of America, Memphis, TN. <a href="http://www.cotton.org/beltwide/proceedings/2005-2016/index.htm">http://www.cotton.org/beltwide/proceedings/2005-2016/index.htm</a> Rothrock, C., S. Winters, T. W. Allen, J. D. Barham, A. B. Beach, M. B. Bayles, P. D. Colyer, H. M. Kelly, R. C. Kemerait, G. W. Lawrence, K. Lawrence, H. L. Mehl, P. Price, and J. Woodward. 2016. Report of the cottonseed treatment committee for 2015. Proceedings of the 2016 Beltwide Cotton Conference Vol. 1: 117-122. National Cotton Council of America, Memphis, TN. <a href="http://www.cotton.org/beltwide/proceedings/2005-2016/index.htm">http://www.cotton.org/beltwide/proceedings/2005-2016/index.htm</a> Smith, H. R., G. W. Lawrence, R. L. Harkess, K. S. Lawrence, D. J. Lang, J. M. Phillips, and P. R. Knight. 2016. Performance of commercial G. hirsutum varieties grown in R. reniformis infested soils with and without nematicides. Proceedings of the 2016 Beltwide Conference Vol 1: 743-761. National Cotton Council of America, Memphis, TN. <a href="http://www.cotton.org/beltwide/proceedings/2005-2016/index.htm">http://www.cotton.org/beltwide/proceedings/2005-2016/index.htm</a> Smith, H. R., G. W. Lawrence, R. L. Harkess, K. S. Lawrence, D. J. Lang, J. M. Phillips, and P. R. Knight. 2016. Effects of nematicide seed treatments with and without foliar applications of Vydate-CLV on the growth and development of G. hirsutum grown in R. reniformis infested soils. Proceedings of the 2016 Beltwide Conference Vol 1: 781-797. National Cotton Council of America, Memphis, TN. <a href="http://www.cotton.org/beltwide/proceedings/2005-2016/index.htm">http://www.cotton.org/beltwide/proceedings/2005-2016/index.htm</a> Subramani, S., Govindan, S., Sundararaj, P., Hafez, S., Nagamony, P., and Sundararaj, N. 2016. Evaluation of shielding efficacy of bovine serum albumin and poly ethylene amine on graphene oxide by using the nematode model Caenorhabiditis elagans. 48th Annual Meeting of the Organization of Nematologoists of Tropical America and 55th Annual meeting of the Society of Nematologists, Montreal, Canada. Till, S. R., and K. S. Lawrence. 2016. Fungicide seed treatments for control of Rhizoctonia solani in upland cotton in Alabama, 2015. Report No. 10:FC013. DOI: 11.1094/PDMR10. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/fc013.asp">http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/fc013.asp</a> Till, S., K. Lawrence, K. Glass, and D. Schrimsher. 2016. Evaluation of cotton cultivars in the presence and absence of reniform nematode and the efficacy of Velum total. Proceedings of the 2016 Beltwide Conference Vol 1: 590-592. National Cotton Council of America, Memphis, TN. <a href="http://www.cotton.org/beltwide/proceedings/2005-2016/index.htm">http://www.cotton.org/beltwide/proceedings/2005-2016/index.htm</a> Xiang, N., and K.S. Lawrence. 2016. Evaluation of the experimental compounds for soybean seedling disease management in North Alabama, 2015. Report No. 10:FC103. DOI: 11.1094/PDMR10. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/pdmr/reports/2016/FC103.pdf">http://www.plantmanagementnetwork.org/pub/trial/pdmr/reports/2016/FC103.pdf</a> Xiang, N., and K.S. Lawrence. 2016. Evaluation of the experimental compounds for the control of soybean SDS in North Alabama, 2015. Report No. 10:FC104. DOI: 11.1094/PDMR10. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/fc104.asp">http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/fc104.asp</a> Xiang, N., and K.S. Lawrence. 2016. Evaluation of the experimental compounds for the control of soybean SDS in central Alabama, 2015. Report No. 10:FC105. DOI: 11.1094/PDMR10. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/fc105.asp">http://www.plantmanagementnetwork.org/pub/trial/pdmr/volume10/abstracts/fc105.asp</a> Xiang, N., K. Lawrence, J. Kloepper, and J. McInroy. 2016. 2015 studies of plant growth promoting rhizobacteria for biological control of Meloidogyne incognita on cotton. Proceedings of the 2016 Beltwide Conference Vol 1: 586-589. National Cotton Council of America, Memphis, TN. <a href="http://www.cotton.org/beltwide/proceedings/2005-2016/index.htm">http://www.cotton.org/beltwide/proceedings/2005-2016/index.htm</a> Proceedings Saad L. Hafez and Mahesh P. Pudasaini, 2015. Efficacy of Movento alone or in combinations with other compounds in drip irrigation system for the management of onion nematodes, 2013. Plant Disease management report, Vol. 9. Saad L. Hafez and Mahesh P. Pudasaini, 2015. Effect of Movento alone of in combinations with Vydate or Vapam for control of Columbia root-knot nematode in Potato, 2012. Plant Disease management report, Vol 9. Saad L. Hafez and Mahesh P. Pudasaini. 2015. Optimum timing of Movento application for control of Columbia root-knot nematode in Potato, 2012. Plant Disease management report, Vol 9. Saad L. Hafez and P. Sundararaj. 2015. Effect of Vapam alone or with Adsorb on Columbia root-knot nematode and potato yield, 2011. Plant Disease management report, Vol 9. Saad L. Hafez and P. Sundararaj. 2015. Efficacy of Telone II for the control of Columbia root-knot nematode on potato, 2010. Plant Disease management report, Vol 9. Saad L. Hafez and P. Sundararaj. 2015. Effect of Movento alone or in combinations with Vydate and Vapm on Columbia root-knot nematode and potato yield, 2011. Plant Disease management report, Vol 9. Saad L. Hafez and P. Sundararaj. 2015. Effect of different chemicals for the management of Columbia root-knot nematode on potato, 2011. Plant Disease management report, Vol 9. Saad L. Hafez and P. Sundararaj. 2015. Effect of MCW on Columbia root-knot nematode and potato yield, 2011. Plant Disease management report, Vol 9. Saad L. Hafez and P. Sundararaj. 2015. Effect of MCW-2 on Columbia root-knot nematode and potato yield, 2011. Plant Disease management report, Vol 9. Saad L. Hafez and P. Sundararaj. 2015. Effect of MCW-2 formulations at different rates on potato and root lesion nematode under greenhouse conditions, 2011. Plant Disease management report, Vol 9. Saad L. Hafez and P. Sundararaj. 2015.Effect of MCW-2 alone or in combination with Vydate on Tobacco rattle virus and potato yield, 2011. Plant Disease management report, Vol 9. Saad L. Hafez and P. Sundararaj. 2015. Evaluation of new chemicals for the management of Columbia root-knot nematode on potato, 2010. Plant Disease management report, Vol 9. Sundararaj, P. and S.L. Hafez. 2014. Effect of chemical nematicides on the management of Columbian root knot nematode Meloidogyne chitwoodi on potato. Presented in the AZRA Silber Jubilee International Conference “Probing Biosciences for Food Security & Environmental Safety” on 16-18 February, 2014, held at CRRI, Cuttack, India. Sundararaj, P. and Saad L. Hafez. Efficacy of chemical nematicides for the management of lesion nematodes Pratylenchus neglectus and Pratylenchus thornei on potato in Idaho, USA. Saad L. Hafez and P. Sundararaj. Efficacy of fumigant and non fumigant nematicides for the management of Meloidogyne chitwoodi in potato. Indian Nematology Conference, India, 2014. Saad L. Hafez, Mahesh P. Pudasaini and Ransey Portenier. New chemistries, new mode of action, different formulatin including seed treatment and multi-target for potato, sugar beet and onion nematode management in Idaho. 6th International Congress of Nematology, Cape Town, South Africa. May 4-9, 2014.

Impact Statements

Cover crops and biological can be used to control Meloidogyne chitwoodi

Date of Annual Report: 01/11/2018

Report Information

Annual Meeting Dates: 11/01/2017 - 11/02/2017
Period the Report Covers: 10/01/2016 - 09/30/2017

Participants

Caswell-Chen, Ed (epcaswell@ucdavis.edu) - University of California Davis;
Gleason, Cynthia (cynthia.gleason@wsu.edu) - Washington State University;
Hafez, Saad (shafez@uidaho.edu) – University of Idaho;
Ingham, Russell (inghamr@science.oregonstate.edu) – Oregon State University;
Lawrence, Gary (glawrence@entomology.msstate.edu) – Mississippi State University;
Lawrence, Kathy (lawrekk@auburn.edu) – Auburn University;
Melakeberhan, Haddish (melakebe@anr.msu.edu) – Michigan State University;
Powers, Thomas (tpowers1@unl.edu) – University of Nebraska;
Robbins, Robert (rrobbin@uark.edu) – University of Arkansas;
Roberts, Philip (philip.roberts@ucr.edu) – University of California, Riverside;
Sipes, Brent (sipes@hawaii.edu) – University of Hawaii;
Klink, Vincent (vklink@biology.msstate.edu) – Mississippi State University;
Thomas, Steve (stthomas@nmsu.edu) - New Mexico State University

Brief Summary of Minutes

OSU administrators provided an interesting update on their school and programs. Each state proceeded to report on project objectives. During the business meeting Cindy Gleason was elected Vice Chair and Inga Zasada was elected Secretary. The 2018 meeting will be held in Hawaii in early November.

Minutes Attachment:

W3186 Minutes 2017.docx

Accomplishments

Objective 1:   Characterize genetic and biological variation in nematodes relevant to crop production and trade. Ditylenchus dipsaci was initially confirmed in New Mexico in 2015. The confirmation triggered a systematic survey of commercial onion fields to detect additional infested sites. Putative Ditylenchus spp. were recovered at low numbers (< 60/100 cm3 soil) from 21 fields. Multiple single-nematode specimens were collected from each infested field and identified using direct sequencing of 18S and ITS regions of the rRNA genes. When identified using only 18S sequence data, 60% of individuals were identified as D. dipsaci (99% similarity), 27% as D. destructor (98% similarity), with the remainder somewhat resembling D. destructor (92-94% similarity) – both of which are species of international regulatory concern that would prevent export to Canada (primary foreign market for NM onions).  When direct sequencing data was expanded to include the ITS-1 region, none of the individuals were identified as D. dipsaci or D. destructor.  Species with the greatest similarity to those recovered included D. arachis (92% similarity) and D. persicus (90% similarity), which are not currently species of regulatory concern.  These result show the importance of using combined 18S and ITS1 rRNA sequences to identify Ditylenchus species for regulatory purposes.    Species identification of Meloidogyne spp. (root-knot nematode, RKN) is an important tool to offer growers because it is beneficial for planning and implementing a crop rotation to reduce the impact of these yield-limiting nematodes. Morphological measurements, differential-host test, and molecular analysis were evaluated for their ability to quickly and accurately identify RKN species. Seventy five samples from 14 counties in Alabama were collected from cotton, soybean, corn, peanut, sweet potato, squash, pepper, kiwi, turmeric, and turf. Primers used for PCR include those that identify commonly found RKN species: M. incognita, M. arenaria, M. javanica, M. hapla, M. fallax, M. chitwoodi, and M. enterolobii. Of these samples, 73 were identified as M. incognita (97%), and two were identified as M. arenaria (3%). These species were identified through the differential-host test and PCR using primer sets IncK-14F/IncK-14R (M. incognita) and Far/Rar (M. arenaria). Overall, M. incognita is the most prevalent species of root-knot nematode that has been found on cropping systems in Alabama during this project. Cytochrome Oxidase C Subunit 1 (COI) barcoding datasets of major groups of plant- and insect-parasitic nematodes have been added. Recent additions include: Heterodera specimens reproducing on alfalfa  from two states; Meloidogyne hapla on alfalfa in Nebraska; Aphelenchoides besseyi from Louisiana; Heterorhabditis/Steinernema: addition of native isolates from central Nebraska. Criconematoidea: two new species have been described and new host reproduction information is available for Mesocriconema nebraskense; Pratylenchus: isolates from across the Great Plains region are being added with 6 major haplotype groups primarily found in corn and wheat. There is still uncertainty about Brazilian A.besseyi reproducing on forage grasses. There are 5 described species on the Aphelenchoides tree and multiple groups of unknown species. The origin of the reniform nematode, Rotylenchulus reniformis, on Oahu and its spread across the state is unknown. Microsatellite markers (SSR) and pedigree analysis provided an understanding of the dispersal of this nemaotde. The SSR markers RR 2-5, RR2-6, RR3-3, RR3-8, RR4-1, RR4-4, RR4-5, RR 1-5 and RR2, RR5 displayed variation within loci. The RR2-5 marker produced 8% double bands and 72% single bands. Similar double bands were observed in RR2-6 (8% double bands, 56% single band, and 36% no band). RR3-3 produced 100% single bands whereas RR3-8 and RR4-1 had 40% single bands and 60% no bands.  RR4-4 gave 54% single bands and 46% no bands. RR1-5, RR2, RR 4-5 and RR5 did not amplify any DNA in the Oahu population. Theses SSR markers have detected differences within the Oahu population and differences among the Oahu population and other populations. The variation detected may indicate that the Oahu population is distinct compared to isolates tested by Leach et al. Twelve oak species were evaluated as hosts of the pecan root-knot nematode (Meloidogyne partityla). Cork and Pin oak allowed the production of galls and egg masses, while Holly, Tabor, and burr Oaks produced galls only. English Walnut (Juglans regia) also allowed production of galls and egg masses. Over 200 soybean Plant Introductions reported to have a high level of Soybean Cyst Nematode (SCN) resistance and 204 with moderate SCN for resistance were evaluated with the reniform nematode (Rotylenchulus reniformis). Of those with a high level of resistance 44 PIs have resistance to reniform nematodes. For those with moderate resistance, 5 PIs showed reniform reproduction not different than than the resistant standard “Hartwig.” Correlation of reproduction and phenotypes could be useful in identifying soybean PIs with resistance to both SCN and reniform nematodes. Over 400 samples have been identified to species with M. incognita the most common root-knot nematode in Arkansas. Understanding parasitic variability in the northern root-knot nematode (NRKN, Meloidogyne hapla) and soybean cyst nematode (Heterodera glycines, SCN) and their adaptation in a given soil biophysical environment are among the long term studies in our program. NRKN is among the most problematic plant-parasitic nematodes in vegetable production in the northern hemisphere where there are no commercially available resistant cultivars and its parasitic variability is a major challenge. Establishing NRKN’s distribution and adaptation in Michigan vegetable production systems relative to soil types, other plant-parasitic and beneficial nematodes, and the environment they inhabit is one of the least known areas. Testing the fitness of different populations of NRKN against Midwest adapted potato, celery, and carrot cultivars, and the effect of soil biophysiochemical conditions on NRKN populations provided a proof-of-concept for location-specific approaches to managing parasitic variability in production systems. These studies led to on-going studies to demonstrate the interaction of NRKN population in different soil types and ecoregions in Michigan and emerging fresh market carrot cultivars with resistance to NRKN. We are rebuilding our cultures of both nematodes collected from different locations within Michigan soils. The NRKN cultures are being re-tested against emerging NRKN-resistant fresh market carrot cultivars. Another important line of investigation is understanding how, if any, NRKN populations’ parasitic behavior may be directly or indirectly influenced by biophysiochemical changes in their environment. We will be using a combination of the soil food web (SFWM) and fertilizer use efficiency (FUE) models to characterize the outcomes that lead to location-specific conditions in the specific soil/farm environments in which NRKN populations exist. The SFWM identifies the agronomic practices driven biophysiochemical outcomes from worst to best case scenarios for soil nutrient cycling, agroecosystem suitability and overall soil health.  The FUE model separates nutrient deficiency and toxicity and measures integrated efficiency of the agronomic practices on suppressing harmful organisms while improving beneficial organisms, nutrient cycling and overall soil health. Objective 2:  Determine nematode adaptation processes to hosts, agro-ecosystems and environments. Mesocriconema nebraskense, an endemic species, is causing economic damage to introduced bent grass (Agrostis stolonifera) in golfcourse greens in New Mexico. Population densities ranged from 670-14,964/100 cm3 soil.  Suppression of nematodes to < 400/100 cm3 soil resulted in bent grass recovery. The nematode species was confirmed by two W3186 project members. The species is broadly distributed throughout native grasslands in central North America that contain gramineaceous plants also common to the ‘southern desert basin, plains, and mountains grasslands’ plant community present in several study sites in  NM. Knowledge of the susceptibility of perennial xeriscape plants to Meloidogyne incognita will provide valuable information regarding the possible presence of resistance genes within the host population.  The reproductive capacity, expressed as  a reproductive factor (RF), for each species will be used to rate the perennials as “good”, “poor”, or “non-hosts” and results shared with nurseries, landscape professionals, and home owners for consideration when selecting plants for use in root-knot nematode infested soil. Common turmeric (Curcuma longa L.), a spice crop native to India, is a niche crop for Alabama. Plants exhibit chlorosis, stunting, and marginal leaf necrosis. Symptomatic plants were collected and root systems exhibited numerous galls, typical of Meloidogyne infection. Nematode eggs were extracted and identified as M. incognita. Meloidogyne incognita-inoculated turmeric selections CL2 and CL7 exhibited significantly reduced average plant height, shoot fresh weight, and root fresh weight with the measurements being 31%, 50%, and 26% of those of the control, respectively. Inoculated selection CL3 did not present significant differences with the control in terms of plant development. Final nematode population densities on CL2, CL3, and CL7 ranged from 19-319 eggs per gram of root, 1-2527, and 41-4703 eggs per gram of root, respectively. Reproductive factor (RF), defined as the final nematode population density divided by the initial inoculum density, was calculated to be 0.6, 4.1, and 2.1 for CL2, CL3, and CL7, respectively. Consequently, turmeric selections CL3 and CL7 were susceptible to the nematode, as their RF values were greater than 1. Turmeric selection CL2, on the other hand, was somewhat resistant to the nematode as its RF value was less than 1. To our knowledge, this is the first report of Meloidogyne incognita infecting Curcuma longa in the United States. Because M. incognita has been recorded in 46 out of Alabama’s 67 counties, potential growers of turmeric should consider nematode management when developing a holistic integrated pest management plan. As shown in greenhouse testing, turmeric selections differ in host suitability to M. incognita race 3. Variety selection will prove an important step to successful turmeric production in the state of Alabama. A harpin elicitor induces the expression of a coiled-coil nucleotide binding leucine rich repeat (CC-NB-LRR) defense signaling gene and other genes functioning during defense to parasitic nematodes. The bacterial effector harpin induces the transcription of the Arabidopsis thaliana (thale cress) NON-RACE SPECIFIC DISEASE RESISTANCE 1/HARPIN INDUCED1 (NDR1/HIN1) coiled-coil nucleotide binding leucine rich repeat (CC-NB-LRR) defense signaling gene. In Glycine max (soybean), Gm-NDR1-1 transcripts have been detected within root cells undergoing a natural resistance reaction to parasitism by the syncytium-forming nematode Heterodera glycines (soybean cyst nematode [SCN]), suggesting that Gm-NDR1-1 functions in the defense response. Expressing Gm-NDR1-1 in Gossypium hirsutum (cotton) leads to resistance to Meloidogyne incognita (root knot nematode [RKN]) parasitism. In experiments presented here, the heterologous expression of Gm-NDR1-1 in G. hirsutum impairs Rotylenchulus reniformis (reniform nematode) parasitism. These results are consistent with the hypothesis that Gm-NDR1-1 expression functions broadly in generating a defense response. To examine a possible relationship with harpin, we evaluated G. max plants topically treated with harpin for induction of the transcription of Gm-NDR1-1. The result indicates the topical treatment of plants with harpin, itself, may lead to impaired nematode parasitism. Topical harpin treatments are shown to impair G. max parasitism by H. glycines, M. incognita and R. reniformis and G. hirsutum parasitism by M. incognita and R. reniformis. How harpin could function in defense has been examined in experiments showing it also induces transcription of G. max homologs of the proven defense genes ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1), TGA2, galactinol synthase, reticuline oxidase, xyloglucan endotransglycosylase/hydrolase, alpha soluble N-ethylmaleimide-sensitive fusion protein (-SNAP) and serine hydroxymethyltransferase (SHMT). In contrast, other defense genes are not directly transcriptionally activated by harpin. The results indicate harpin induces pathogen associated molecular pattern (PAMP) triggered immunity (PTI) and effector-triggered immunity (ETI) defense processes in the root, activating defense to parasitic nematodes. RNA has been isolated from Glycine max (soybean) root cells undergoing the process of defense to Heterodera glycines (soybean cyst nematode). The RNA has been used in gene expression analyses. The procedure has led to the identification of candidate resistance genes. A gene testing platform has been developed to functionally test these genes. The procedure has examined hundreds of genes with some functioning effectively in defense. The analysis has demonstrated the importance of various cellular processes to defense and has identified genes that previously had no known role in defense. RNA has been isolated from Glycine max (soybean) root cells undergoing the process of defense to a root pathogen. The RNA has been used in gene expression analyses, leading to the identification of candidate resistance genes. A gene testing platform has been developed to functionally test these genes with the aim of determining if the genes function during the process of defense. The procedure has examined hundreds of genes with some functioning effectively in defense. The analysis has demonstrated the importance of various cellular processes to defense and has identified genes that previously had no known role in defense. Objective 3:  Develop and assess nematode management strategies in agricultural production systems. The project team members are evaluating multiple tactics to manage population densities of nematodes in crops and the landscape. Approaches include the evaluation of chemicals and biological agents. The potential of 662 plant growth-promoting rhizobacteria (PGPR) strains to kill Meloidogyne incognita J2 in vitro and to manage M. incognita in greenhouse, microplot, and field trials was tested. Mortality of M. incognita by the PGPR strains ranged from 0 to 100% with an average of 39%. Among the PGPR strains examined, 212 of 662 strains (or 33%) caused significantly greater mortality percent of M. incognita J2 than the untreated control. Bacillus spp. caused  greater mortality percentage when compared with the other genera of PGPR. In subsequent trials, B. velezensis strain Bve2 reduced M. incognita eggs per gram of cotton root in the greenhouse trials at 45 days after planting (DAP) similarly to the commercial standards Abamectin and Clothianidin plus B. firmus I-1582. Bacillus mojavensis strain Bmo3, B. velezensis strain Bve2, B. subtilis subsp. subtilis strain Bsssu3, and the Mixture 2 (Abamectin + Bve2 + B. altitudinis strain Bal13) suppressed M. incognita eggs per gram of root in the microplot at 45 DAP. Bacillus velezensis strains Bve2 and Bve12 also increased seed-cotton yield in the microplot and field trials. Overall, results indicate that B. velezensis strains Bve2 and Bve12, B. mojavensis strain Bmo3, and Mixture 2 have potential to reduce M. incognita population density and to enhance growth of cotton when applied as in-furrow sprays at planting.     Biological control is also being evaluated for management of H. glycines. The efficacy of the biological products ALB EXP Bacteria 1, 2, and 3, Burkholderia sp. alone and in combination with bacterial metabolites Saponin, and Harpin, a standard Abamectin and an untreated control were evaluated. All seeds were treated by Albaugh, LLC. Treated seeds were planted and inoculated with H. glycines (2500 eggs). At harvest, no negative effects were recorded from any treatment on soybean growth.  Seed treatments significantly reduced eggs and cysts of H. glycines compared with the untreated control. Seed treatments were similar in efficacy to the standard, Abamectin. H. glycines J2 populations were significantly lower in the seed treatments compared with the control except in treatments ALB EXP Bacteria 1 and 2.  When two systemic acquired resistance products were added to Burkholderia sp., both cyst and egg numbers were lower compared to Burkholderia alone. Agricultural chemical companies are developing products for nematode control in row and vegetable crops. Efficacy studies have been conducted to determine their effect on nematode infestations of field crops. Many are still in their early developmental stages therefore only numbers or codes are available for some of the listed products. In microplot studies, on pinto bean receiving 5.0 and 7.0 pt/acre fluensulfone M. incognita populations were 39% and 20% lower respectively compared to untreated control plots or those treated with 3.5 pt/acre fluensulfone.  Management of M. incognita in direct-seeded chile pepper (Capsicum annuum cv Sandia) to fluensulfone broadcast, banded, and to 1,3-dichloropropene under furrow irrigation is being evaluated.  Management of M. incognita in grape (Pinot Grigio scion on ‘Freedom’ rootstock) with two rates of fluensulfone and spirotetramat shows numbers of second-stage juveniles (J2) were 84%, 74%, and 53% less than untreated plots in response to treatment with 8 oz/acre spirotetramat, 3.5 pt/ acre and 5.0 pt/acre fluensulfone, respectively.  Average berry yields were 30% greater in all treated plots compared to the untreated controls. Little to no tolerance for infection of potato tubers by Columbia root-knot nematodes (CRKN, Meloidogyne chitwoodi) exists. Strategies that reduce reproduction by CRKN that could either result in sufficient control alone or reduce population densities are being investigated including MeloCon, Purpureocillium lilacinus strain 251; Bio Blend containing Agrothrive fermented fish product; Soil Medic; Sobec; and Soyaplex; Hyper Galaxy, a consortia of plant growth-promoting rhizobacteria (PGPR) including Azospirillum brazilense, Azotobacter chroococcum, Bacillus azotofixans, Pseudomonas fluorescens, and Pseudomonas putida; and BioFit N, containing Azotobacter chroccocum, Bacillus subtillis, Bacillus megaterium, Bacillus mycoides, and Trichoderma harzianum. CRKN host (Barley ‘C-69’) and nonhost (radish ‘Terra Nova’) were treated with MeloCon (2 lb/acre) or BioFit N (1 lb/acre). Total eggs and J2/pot in barley were 42,287, 39,181, and 28,850 and in radish were 35, 0 and 0 for pots that were untreated or treated with MeloCon or BioFit N, respectively. After harvest, a ‘Stevens’ wheat (excellent host) seedling was transplanted into the remaining soil from each pot to assess for any residual suppression of CRKN from the different treatments. Eggs and J2/pot reached high levels in all pots that had been planted to barley (63,679, 29,287, and 46,165) whereas the numbers of CRKN recovered from pots that had been initially planted to radish were extremely low (134, 106, and 5/pot) from pots that were untreated or treated with MeloCon or BioFit N, respectively. Fresh shoot biomass of ‘Stevens’ wheat, ‘C-69’ barley or ‘Sordan 79’ sudangrass at a rate of 15 tons/acre was mixed into soil containing 5,000 CRKN eggs and then either untreated or treated with MeloCon (4 lb/acres). CRKN reproduction factors were calculated. None of the biomass amendments had any effect on CRKN reproduction compared to that in the unamended pots. MeloCon significantly reduced reproduction in the unamended pots but had no effect on pots that had been amended with plant biomass. Soil infested with CRKN was treated with MeloCon at simulated in-furrow rates of 2, 4, or 6 lb/acre and received no further treatment for the rest of the trial. Another group of pots was treated with Bio Blend at 10 gal/acre, Hyper Galaxy at 4 oz/acre, or BioFit N at 1 lb/acre applied as a simulated in-furrow at planting and as chemigation applications in ½ in. water at 30 and 60 days. An additional group of pots received MeloCon at 2 lb/acre plus BioBlend, Hyper Galaxy or BioFit N at 30 and 60 days. The 2 lb rate of MeloCon had a significantly lower RF than in the untreated pots and the 4 lb rate had a significantly lower RF than in the untreated pots or the pots that received the 2 lb/acre rate. The 6 lb rate had a significantly lower RF than the untreated control but was not different than either the 2 or 4 lb rates. Pots treated with Bio Blend, Hyper Galaxy and BioFit N alone all had significantly lower RF values than the untreated control. Hyper Galaxy had the lowest RF value which was significantly less than that for BioFit N. None of the combination treatments of 2 lb MeloCon at planting  plus Bio Blend, Hyper Galaxy, or BioFit N at 30 and 60 days had an RF value that was different from that of the 2 lb/acre MeloCon treatment alone. Furthermore, the combination treatments of MeloCon plus Bio Blend and MeloCon plus Hyper Galaxy had higher RF values than the corresponding treatment without MeloCon. Sixty six soybean breeder lines were tested for reniform resistance. The lines represent breeders from Arkansas, Clemson, Georgia, and Missouri. Of these 66 lines, two each from Clemson and Georgia, ten of Missouri, and none from Arkansas showed reniform nematode resistance: reproduction of the nematode on these lines did not exceed its reproduction on the resistant check “Hartwig.” These 14 lines may be useful in breeding for reniform resistance in commercial lines.

Publications

Journal Articles: <ol> <li>Aljaafri, W.A.R., McNeece, B.T., Lawaju, B.R., Sharma, K., Niruala, P.M., Pant, S.R., Long, D.H., Lawrence, K.S., Lawrence, G.W., Klink, V.P. 2017. A harpin elicitor induces the expression of a coiled-coil nucleotide binding leucine rich repeat (CC-NB-LRR) defense signaling gene and others functioning during defense to parasitic nematodes. Plant Physiology and Biochemistry 121:161-175.</li> <li>Asiedu, O., C. K. Kwoseh, H. Melakeberhan, and T. Adjeigyapong.2017. Nematode distribution in cultivated and undisturbed soils of Guinea Savannah and Semi-deciduous Forest zones of Ghana. Geoscience Frontiers. <a href="https://urldefense.proofpoint.com/v2/url?u=https-3A__doi.org_10.1016_j.gsf.2017.07.010&d=DwMF-g&c=nE__W8dFE-shTxStwXtp0A&r=F87v_WD2MTUolqz9ZmgwMg&m=G-WaWb_wTkKT8rbMscth5Q1UgoEjepe1sX6OC4Uudc8&s=5cfP0JvjcQFCUAJP1JAngWrhsDS8evwmmO34adfrM4k&e=">https://doi.org/10.1016/j.gsf.2017.07.010</a>.</li> <li>Crutcher, F. K., L. S. Puckhaber, R. K. Stipanovic, A. A. Bell, R. L. Nichols, K. S. Lawrence, J. Liu. 2017 Microbial resistance mechanisms to the antibiotic and phytotoxin Fusaric acid. Journal of Chemical Ecology October 6, 2017. DOI 10.1007/s10886-017-0889-x</li> <li>Dodge, D., K. S. Lawrence, W. Groover, S. Till, D. Dyer, and M. Hall. 2017. Soybean variety yield comparison with and without Abamectin for management of Rotylenchulus reniformis in Belle Mina Alabama, 2016. Report No. 11:N017. DOI: 10.1094/PDMR11. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N017.pdf">http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N017.pdf</a></li> <li>Dodge, D., K. S. Lawrence, W. Groover, S. Till, D. Dyer, and M. Hall. 2017. Soybean variety yield comparison with and without Abamectin for management of root-knot nematode in Fairhope Alabama, 2016. Report No. 11:N018. DOI: 10.1094/PDMR11. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N018.pdf">http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N018.pdf</a></li> <li>Dodge, D., K. S. Lawrence, W. Groover, S. Till, D. Dyer, and M. Hall. 2017. Soybean variety yield comparison with and without Abamectin for management of root-knot nematode in Brewton Alabama, 2016. Report No. 11:N019. DOI: 10.1094/PDMR11. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N019.pdf">http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N019.pdf</a></li> <li>Dodge, D., K. S. Lawrence, W. Groover, S. Till, D. Dyer, and M. Hall. 2017. Soybean variety yield comparison with and without Abamectin for management of root-knot nematode in Tallassee Alabama, 2016. Report No. 11:N020. DOI: 10.1094/PDMR11.The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N020.pdf">http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N020.pdf</a></li> <li>Dodge, D., K. S. Lawrence, E. Sikora and D. P. Delaney. 2017. Evaluation of Soybean Varieties with Avicta for Control of Rotylenchulus Reniformis. Proceedings of the 2017 Beltwide Cotton Conference Vol. 1: 198-200. National Cotton Council of America, Memphis, TN. <a href="http://cotton.org/beltwide/proceedings/2010-2017/index.htm">http://cotton.org/beltwide/proceedings/2010-2017/index.htm</a></li> <li>Dyer, D., K. S. Lawrence, S. Till, D. Dodge, W. Groover, N. Xiang, and M. Hall. 2017. A potential new biological nematicide for reniform management in north Alabama, 2016. Report No. 11:N012. DOI: 10.1094/PDMR11. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N012.pdf">http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N012.pdf</a></li> <li>Dyer, D., K. S. Lawrence, S. Till, D. Dodge, W. Groover, N. Xiang, and M. Hall. 2017. A potential new biological nematicide for root-knot management in Alabama, 2016. Report No. 11:N013. DOI: 10.1094/PDMR11. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N013.pdf">http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N013.pdf</a></li> <li>Dyer, D., N. Xiang, and K. S. Lawrence. 2017. First report of Catenaria anguillulae infecting Rotylenchulus reniformis and Heterodera glycines in Alabama. Plant Disease. 101(8):1547. https://doi.org/10.1094/PDIS-03-17-0366-PDN.</li> <li>Dyer, D., K. S. Lawrence and D. Long. 2017. A Potential New Biological Nematicide for Meloidogyne Incognita and Rotylenchulus Reniformis Management on Cotton in Alabama. Proceedings of the 2017 Beltwide Cotton Conference Vol. 1: 208-210. National Cotton Council of America, Memphis, TN. <a href="http://cotton.org/beltwide/proceedings/2010-2017/index.htm">http://cotton.org/beltwide/proceedings/2010-2017/index.htm</a></li> <li>A. Ahmed, B.S. Sipes, and A.M. Alvarez. 2017. Postharvest diseases of tomato and natural products for disease management. African Journal of Agricultural Research: 12:684-691. DOI: 10.5897/AJAR2017.12139 </li> <li>A. Ahmed, B.S. Sipes, and A.M. Alvarez. 2016. Natural products to control postharvest gray mold of tomato fruit - possible mechanisms. Journal of Plant Pathology and Microbiology 7:1-7. DOI: 10.4172/2157-7471.1000367.</li> <li>French, J.M., J. Beacham, A. Garcia, N.P. Goldberg, S.H. Thomas, and S.F. Hanson.   First Report of Stem and Bulb Nematode Ditylenchus dipsaci on Garlic in New Mexico.  Plant Health Progress http://dx.doi.org/10.1094/PHP-12-16-0069BR.</li> <li>Gosse, H. N., K. S. Lawrence, and Sang-Wook Park. 2017. Underground mystery: the role of chemotactic attractants in plant root and phytonematode interactins. Scientia Ricerca 1(2): 83-87.</li> <li>Grabau, Z.J., Z.T.Z. Maung, C. Noyes, D. Baas, B.P. Werling, D.C. Brainard, and H. Melakeberhan. Effects of cover crops on Pratylenchus penetrans and the nematode community in carrot production. Journal of Nematology. Journal of Nematology 49, 114-123.</li> <li>Groover, W., K.S. Lawrence, N. Xiang, S. Till, D. Dodge, D. Dyer, and M. Hall. 2017. Cotton variety selection with and without Velum Total for root-knot nematode management in central Alabama, 2016. Report No. 11:N014. DOI: 10.1094/PDMR11. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N014.pdf">http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N014.pdf</a></li> <li>Groover, W., K. S. Lawrence, N. Xiang, S. Till, D. Dodge, D. Dyer, and M. Hall. 2017. Cotton variety selection with and without Velum Total for reniform management in north Alabama, 2016. Report No. 11:N015. DOI: 10.1094/PDMR11. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N015.pdf">http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N015.pdf</a></li> <li>Groover, W., K. S. Lawrence, N. Xiang, S. Till, D. Dodge, D. Dyer, and M. Hall. 2017.Cotton seed treatment combinations for Rotylenchulus reniformis control and maximization of yield in north Alabama, 2016. Report No. 11:N016. DOI: 10.1094/PDMR11. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N016.pdf">http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N016.pdf</a></li> <li>Groover, W. K. S. Lawrence, N. Xiang, S. Till, D. Dodge, D. Dyer, and M. Hall. 2017. Nematicide combinations for Rotylenchulus reniformis management in north Alabama, 2016. Report No. 11:N009. DOI: 10.1094/PDMR11. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N009.pdf">http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N009.pdf</a></li> <li>Hall, M., K. Lawrence, W. Groover, D. Shannon, and T. Gonzalez. 2017. First Report of the Root-Knot Nematode (Meloidogyne incognita) on Curcuma longa in the United States. Plant Disease 101 (10):1826. https://doi.org/10.1094/PDIS-03-17-0409-PDN.</li> <li>Hall, M., K. S. Lawrence, D. Dodge, D. Dyer, W. Groover, S. Till, and N. Xiang. 2017. Varietal and nematicidal application responses in central Alabama soils, 2016. Report No. 11:N024. DOI: 10.1094/PDMR11. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N024.pdf">http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N024.pdf</a></li> <li>Hall, M., K. S. Lawrence, D. Dodge, D. Dyer, W. Groover, S. Till, and N. Xiang. 2017. Varietal and nematicidal application responses in north Alabama soils, 2016. Report No. 11:N2025. DOI: 10.1094/PDMR11. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N025.pdf">http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N025.pdf</a></li> <li>Hall, M., K. S. Lawrence, D. Dodge, D. Dyer, W. Groover, S. Till, and N. Xiang. 2017. Velum Total and Vydate-L drip irrigation applications for southern root-knot nematode management in south Alabama, 2016. Report No. 11:N007. DOI:10.1094/PDMR11. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N007.pdf">http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N007.pdf</a></li> <li>Hall, M., K. S. Lawrence, D. Dodge, D. Dyer, W. Groover, S. Till, and N. Xiang. 2017. Velum Total and Vydate-L drip irrigation applications for southern root-knot nematode management in south Alabama, 2016. Report No. 11:N008. DOI: 10.1094/PDMR11. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N008.pdf">http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N008.pdf</a></li> <li>Ingham, R.E. 2017. Nematode management in the face of short supply of Telone and Vydate. Potato Progress. 17(7):1-5.</li> <li>Kim, Ki-Seung, Dan Qiu, Tri D. Vuong, Robert T. Robbins, J. Grover Shannon, Zenglu Li, and Henry T. Nguyen. 2016. Advancements in breeding, genetics, and genomics for resistance to three nematode species in soybean. Theoretical and Applied Genetics 2295-2311.</li> <li>Khanal, C., R.T. Robbins, Faske, A.L. Szalanski, E.C. McGawley, and C. Oversteet. 2016. Identification and haplotype designation of Melogogyne spp. of Arkansas using molecular diagnostics. 2016. Nematropica 46:261-270.</li> <li>Klink VP, McNeece BT, Pant SR, Sharma K, Nirula PM, Lawrence GW. 2017. Components of the SNARE-containing regulon are co-regulated in root cells undergoing defense. Plant Signalling and Behavior Feb; 12(2):e1274481.</li> <li>Land, C. J., K. S. Lawrence, C. H. Burmester, B. Meyer. 2017. Cultivar, irrigation, and soil contribution to the enhancement of Verticillium wilt disease in cotton. Drop Protection 96:1-6.</li> <li>Lawrence, K. S., N. Xiang, W. Groover, S. Till, D. Dodge, D. Dyer, and M. Hall. 2017. Evaluation of commercial cotton cultivars for resistance to Fusarium wilt and Root-knot nematode, 2016. Report No. 11:N006. DOI: 10.1094/PDMR11. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N006.pdf">http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N006.pdf</a></li> <li>Lee, M.W., A. Huffaker, D. Crippen, R.T. Robbins, and F. Goggin. 2017. Plant Elicitor Peptides Promote Plant Defenses against Nematodes in Soybean. Molecular Plant Pathology. Date: 27-June-2017, pp. 1 – 12, DOI : 10.1111/mpp.12570.</li> <li>McNeece BT, Pant SR, Sharma K, Nirula PM, Lawrence GW, Klink 2017. A Glycine max homolog of NON-RACE SPECIFIC DISEASE RESISTANCE 1 (NDR1) alters defense gene expression while functioning during a resistance response to different root pathogens in different genetic backgrounds. Plant Physiology and Biochemistry 114:60-71.</li> <li>Moye, Hugh. H. Jr., N. Xiang, K. Lawrence, and E. van Santen. 2017. First Report of Macrophomina phaseolina on Birdsfoot Trefoil (Lotus corniculatus) in Alabama. Plant Disease 101 (5): 842. https://doi.org/10.1094/PDIS-12-16-1750-PDN.</li> <li>Olson, M., Harris, T., Higgins, R., Mullin, P., Powers, K., Olson, S. and Powers, T.O., 2017. Species Delimitation and Description of Mesocriconema nebraskense sp. (Nematoda: Criconematidae), a morphologically cryptic, parthenogenetic species from North American grasslands. Journal of Nematology, 49(1) 42-68.</li> <li>Powers, T. O., Harris, T., Higgins, R., Mullin, P., and Powers, K. 2017. An 18S rDNA perspective on the classification of Criconematoidea. Journal of Nematology 49(3):236–244. 2017.</li> <li>Till, S. R., K.S. Lawrence, N. Z. Xiang, W. L. Groover, D. J. Dodge, D. R. Dyer, and M. R. Hall. 2017. Yield loss of five corn hybrids due to the root-knot nematode and nematicide evaluation in Alabama, 2016. Report No. 11:N021. DOI: 10.1094/PDMR11. The American Phytopathological Society, St. Paul, MN. <a href="https://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N021.pdf">https://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N021.pdf</a></li> <li>Till, S. R., K. S. Lawrence, N. Z. Xiang, W. L. Groover, D. J. Dodge, D. R. Dyer, and M. R. Hall. 2017. Corn hybrid and nematicide evaluation in root-knot nematode infested soil in Alabama, 2016. Report No. 11:NO23. DOI: 10.1094/PDMR11. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N023.pdf">http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N023.pdf</a></li> <li>Till, S. R., K. S. Lawrence, N.Z. Xiang, W.L. Groover, D.J. Dodge, D.R. Dyer, and M.R. Hall. 2017. Cotton variety evaluation with and without Velum Total for root knot management in south Alabama, 2016. Report No. 11:N022. DOI: 10.1094/PDMR11. The American Phytopathological Society, St. Paul, MN.  <a href="http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N022.pdf">http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N022.pdf</a></li> <li>Xiang, Ni, K.S. Lawrence, J.W. Kloepper, P.A. Donald, and J.A. McInroy. 2017. Biological control of Heterodera glycines by spore-forming plant growth-promoting rhizobacteria (PGPR) on soybean. PLOS ONE 12(7): e0181201. https://doi.org/10.1371/journal.pone.0181201.</li> <li>Xiang, Ni, K.S. Lawrence, J.W. Kloepper, P.A. Donald, J.A. McInroy, and G.W. Lawrence. 2017. Biological control of Meloidogyne incognita by spore-forming plant growth-promoting rhizobacteria on cotton. Plant Disease 101(5): 774-784. <a href="http://apsjournals.apsnet.org/doi/pdf/10.1094/PDIS-09-16-1369-RE">http://apsjournals.apsnet.org/doi/pdf/10.1094/PDIS-09-16-1369-RE</a></li> <li>Xiang, N., K. S. Lawrence, W. Groover, D. Dodge, D. Dyer, and S. Till. 2017. Evaluation of Velum Total on cotton for reniform nematode management in North Alabama, 2016. Report No. 11:N010. DOI: 10.1094/PDMR11. The American Phytopathological Society, St. Paul, MN. <a href="http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N010.pdf">http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N010.pdf</a></li> <li>Xiang, N., K.S. Lawrence, W. Groover, D. Dodge, D. Dyer, and S. Till. 2017.Evaluation of Velum Total on cotton for root-knot management in central Alabama, 2016. Report No. 11:N011. DOI: 10.1094/PDMR11. The American Phytopathological Society, St. Paul, MN.<a href="http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N011.pdf">http://www.plantmanagementnetwork.org/pub/trial/PDMR/reports/2017/N011.pdf</a></li> </ol> Published Abstract: <ol> <li>Aljaafri, W.A.R., G.W. Lawrence, S. Lu, V.P. Klink, D.H. Long and K.S. Lawrence 2017. Ability of SAR-Saponin and A bacterial metabolite to reduce the soybean cyst nematode (Heterodera glycines) and the incidence of sudden death syndrome (Fusarium virguliforme). Phytopathology (in press).</li> <li>Aljaafri, W.A.R., G.W. Lawrence, V.P. Klink, S. Lu, D.H. Long and K.S. Lawrence 2017. Biological seed treatments for Soybean Cyst Nematode (Heterodera glycines) management. Journal of Nematology (in press).</li> <li>Bisho R.L., B. T. McNeece, S. R. Pant, K. Sharma, P. Niraula, K.S. Lawrence, G. W. Lawrence, V.P. Klink. 2017. The identification of genes having defense roles to nematodes through a functional development genomic screen. Journal of Nematology (in press).</li> <li>Bisho R.L., B. T. McNeece, S. R. Pant, K. Sharma, P. Niraula, K.S. Lawrence, G. W. Lawrence, V.P. Klink. 2017. A functional developmental genomics screen is identifying genes functioning within cells that function in plant to a root pathogen. Phytopathology (in press).</li> <li>Fatdal, L., B. Sipes, and M. Melzer. 2017. Bioforensic studies in Rotylenchulus reniformis – Sources and origin. Journal of Nematology 48: in press.</li> <li>LaPorte, Patricia, B. Sipes, H. Melakeberhan, C. Chan, A. Sanchez-Perez, and A. Sacbaja 2017. An interdisciplinary assessment of integrated nematode-soil health management for smallholder potato farming systems in western highlands of Guatemala. Journal of Nematology 48: in press.</li> <li>Marquez, J., K.-H.Wang, B.S. Sipes, and Z. Cheng. 2017. Improving soil conditions for entomopathogenic nematodes with no-till cover cropping. Journal of Nematology 48: in press.</li> <li>Noyes, D.C., Z. Hayden, D. Baas, H. Melakeberhan, B. Werling and D.C. Brainard.  2017.  Cover crop effects on nitrogen and weeds in MI processing carrots.  38th International Carrot Conference, CP-102, Bakersfield, CA, March (Oral). <a href="http://ucanr.edu/sites/test02082001/view_oral_presentation_abstracts/production/">http://ucanr.edu/sites/test02082001/view_oral_presentation_abstracts/production/</a></li> <li>Thomas, S.H., J. Beacham, and T.O. Powers. 2017. Suppression of Criconematid-induced injury to golf course greens in New Mexico.  Journal of Nematology 49: (in press).</li> </ol>   Proceedings: <ol> <li>Faske, T., Lonoke, T. W. Allen, Mississippi State University, G. W. Lawrence, Kathy S. Lawrence, H. L. Mehl, R. Norton, Charles Overstreet, and T. Wheeler. 2017. Beltwide Nematode Research and Education Committee Report on Cotton Cultivars and Nematicides Responses in Nematode Soils, 2016. Proceedings of the 2017 Beltwide Cotton Conference Vol. 1: 270-273.  National Cotton Council of America, Memphis, TN. <a href="http://cotton.org/beltwide/proceedings/2010-2017/index.htm">http://cotton.org/beltwide/proceedings/2010-2017/index.htm</a></li> <li>Groover, W., Lawrence, N. Xiang, S. R. Till, D. Dodge, D. R. Dyer and M. Hall. 2017. Yield Loss of Cotton Cultivars Due to the Reniform Nematode and the Added Benefit of Velum Total. Proceedings of the 2017 Beltwide Cotton Conference Vol. 1: 216-219. National Cotton Council of America, Memphis, TN. <a href="http://cotton.org/beltwide/proceedings/2010-2017/index.htm">http://cotton.org/beltwide/proceedings/2010-2017/index.htm</a></li> <li>Hall, M., K. S. Lawrence, D. Dodge, D. R. Dyer, W. Groover, S. R. Till and N. Xiang. 2017. Varietal and Nematicidal Responses of Cotton in Nematode-Infested Soils. Proceedings of the 2017 Beltwide Cotton Conference Vol. 1: 211-215. National Cotton Council of America, Memphis, TN. <a href="http://cotton.org/beltwide/proceedings/2010-2017/index.htm">http://cotton.org/beltwide/proceedings/2010-2017/index.htm</a></li> <li>Ingham, R.E. 2017. Nematode management in the face of short supply of Telone and Vydate. 2017 Proceedings of the Washington - Oregon Potato Conference. Pp. 33-38.</li> <li>Lawrence, K., A. Hagan, R. Norton, T. R. Faske, R. Hutmacker, J. Muller, D. L. Wright, I. Small, R. C. Kemerait, C. Overstreet, P. Price, G. Lawrence, T. Allen, S. Atwell, A. Jones, S. Thomas, N. Goldberg, R. Boman, J. Goodson, H. Kelly, J. Woodward and H. Mehl. 2017. Cotton Disease Loss Estimate Committee Reort, 2016. Proceedings of the 2017 Beltwide Cotton Conference Vol. 1: 150-151. National Cotton Council of America, Memphis, TN. <a href="http://cotton.org/beltwide/proceedings/2010-2017/index.htm">http://cotton.org/beltwide/proceedings/2010-2017/index.htm</a></li> <li>Robbins, R. T., P. Arelli, P. Chen, G. Shannon, S. Kantartzi, Z. Li, T. Faske, J. Vellie, E. Gbur, D. Dombek, and D. Crippe 2017. <a href="http://www.cotton.org/beltwide/proceedings/2005-2017/data/conferences/2017/papers/17360.pdf#page=1">Reniform Nematode Reproduction on Soybean Cultivars and Breeding Lines in 2016</a>. Proceedings Beltwide Cotton Conferences, Dallas, TX, January 4-6, 2017, pp 184-197.</li> <li>Rothrock, C., S. Winters, T. W. Allen, J. D. Barham, W. Barnett, M. B. Bayles, P. D. Colyer, H. M. Kelly, R. Kemerait, G. W. Lawrence, K. Lawrence, H. L. Mehl, P. Price and J. Woodward. 2017. Report of the Cottonseed Treatment Committee for 2016. Proceedings of the 2017 Beltwide Cotton Conference Vol. 1: 153-160. National Cotton Council of America, Memphis, TN. <a href="http://cotton.org/beltwide/proceedings/2010-2017/index.htm">http://cotton.org/beltwide/proceedings/2010-2017/index.htm</a></li> <li>Till, S., K. S. Lawrence, D. Schrimsher and J. R. Jones. 2017. Yield Loss of Ten Cotton Cultivars Due to the Root-Knot Nematode and the Added Benefit of Velum Total. Proceedings of the 2017 Beltwide Cotton Conference Vol. 1: 205-207. National Cotton Council of America, Memphis, TN. <a href="http://cotton.org/beltwide/proceedings/2010-2017/index.htm">http://cotton.org/beltwide/proceedings/2010-2017/index.htm</a></li> <li>Xiang, N., M. S. Foshee, K. Lawrence, J. W. Kloepper and J. A. McInroy. 2017. Field Studies of Plant Growth-Promoting Rhizobacteria for Biological Control of Rotylenchulus Reniformis on Soybean. Proceedings of the 2017 Beltwide Cotton Conference Vol. 1: 201-204. National Cotton Council of America, Memphis, TN. <a href="http://cotton.org/beltwide/proceedings/2010-2017/index.htm">http://cotton.org/beltwide/proceedings/2010-2017/index.htm</a></li> </ol>   Book chapters: <ul> <li>Thomas, S.H. and C. Nischwitz. Chapter 19:  Plant-parasitic nematodes in New Mexico and Arizona.  In Subbotin and J. Chitambar eds. Plant parasitic nematodes in sustainable agriculture of North America. Springer. (in review)</li> </ul>

Impact Statements

Integrated understanding of the relationships among cover crops and rotation crops, the nematode community, and soil health allow growers to make accurate management decisions