Brief Summary of Minutes of Annual Meeting

Minutes MultiState Cooperative Research Project S-1015 November 18 - 19, 2004 Madren Conference Center, Trustee Board Room Clemson, SC Present: Ernest Bernard, Tennessee Senyu Chen, Minnesota Richard Davis, USDA /ARS, Georgia Don Dickson, Florida Jonathan Eisenback, Virginia Bruce Fortnum, South Carolina Charles Johnson, Virginia Steve Koenning, North Carolina Kathy Lawrence, Alabama Gary Lawrence, Mississippi Stephen Lewis, South Carolina John Mueller, South Carolina Gregory Noel, USDA /ARS, Illinois Robert Robbins, Arkansas Guests: Paula Agudelo pagudel@clemson.edu Janete Brito britoj@doacs.fl.state.us Richard Hussey, Retired, Georgia Minutes: Dr. Steve Lewis of Clemson University called the meeting to order at approximately 9:00 a.m. and welcomed all attendees to Clemson University and the meeting. He then asked Dr. Susan Barefood, Chief Operating Officer, South Carolina Experiment Station and Associate Dean, Food Safety and Nutrition to speak. She also welcomed us to Clemson University and Clemson, South Carolina. Each representative then introduced himself or herself and to the respective university they represent. Dr. Ron Lacewell, our Administrative Advisor, made a few announcements. He mentioned that Dr. Mike Fitzner is assigned as our USDA CSREES advisor and would join our meeting on the second day. Dr Lacewell then inspired us with words of guidance to help increase our acceptance as a multistate research group. Our project like all others is continually being reviewed. A few words concerning the length of out last reports and we now have a new format that scales down the amount of paperwork required. Twenty - thirty minute oral reports were then presented by Chuck Johnson of Virginia Tech, Jon Eisenback of Virginia Tech, Ernie Bernard of the Univ. of Tennessee, Paula Agudelo of Clemson University, Steve Lewis of Clemson University, John Mueller of Clemson University, Bruce Fortnum of Clemson University, and Steve Koenning of North Carolina State Univ. After the lunch break we were treated to a tour of the Clemson University campus and visited the new state-of-the-art greenhouse facilities. At 2:00 p.m. state reports were presented by Senyu Chen of Univ. of Minnesota, Kathy Lawrence of Auburn University, Richard Hussey, retired Univ. of Georgia, (presented us with an update on the parasitism gene in the root-knot and soybean cyst nematode), Greg Noel USDA / ARS Illinois and Robert Robbins of Arkansas. David Howle, Head, Department of Plant Industries, currently on the Asian soybean rust subcommittee, joined our group and presented us with a report on the rust issue. He mentioned that the rust had been found in Florida on Kudzu, however the infection was light. All Section 18s for fungicidal materials that are for use on the rust have or are expected to be approved. The meeting then resumed at 8:30 on Friday morning. Mike Fitzner, our USDA, CSREES representative then presented us with an update from Washington. He also stressed the need to show results of our project to provide to the reviewers that the money has been put to good use. State report resumed with reports form Don Dickson of Univ. of Florida, Janete Brito of the Univ. of Florida, Richard Davis USDA / ARS Georgia, and Gary Lawrence Mississippi State University. Dr Steve Lewis then called to order a short business meeting at approximately 10:00a.m. Ron Lacewell emphasized the need to include in our accomplishments a few major what if statements. Ron suggested that when we send our reports to Steve Lewis that we include a so what statement. It was suggested that all reports be received by Nov. 29, 2004. Ron Lacewell will also send the necessary code to Steve in order to submit the report via e-mail. The minutes of the meeting will be attached to the annual report. North Carolina was identified as the 2005 meeting site and Steve Koenning was designated as the chair for this meeting. Steve then invited everyone to attend the 2005 meeting which will be held in Raleigh, NC in the SRIPM center. The meeting date will be similar to this meeting, around November 17 and 18, 2005. Ron Lacewell suggested that we hold a workshop and a discussion ensued regarding possible speakers. Dr. Lacewell suggested that we meet in Washington in 2006. At the mention of no further business, Gary Lawrence asked for everyone to join him in expressing thanks to Steve Lewis for his performance in hosting an excellent 2004 meeting. The meeting Adjourned at 11:35 a.m. Respectfully submitted, Gary Lawrence

Objective 1: Identification, characterization and introgression of genes for resistance and tolerance to nematodes into cotton, peanut, soybean and major fruit and vegetable crops. Cotton: AL - In Alabama, commercial cotton varieties were examined in the greenhouse and the field to determine possible resistance and/or tolerance to the reniform nematode, Rotylenchulus reniformis. The sixty cotton varieties tested in the greenhouse were susceptible to the reniform nematode. The reproductive indexes ranged from 13 to 70 on Sure Grow 747 and Deltapine 424 BGII/RR, respectively. In south Alabama, possible tolerance was indicated when seed cotton yields were not (P < 0.05) increased by the application of a nematicide for Stoneville 4793 RR, Fiber Max 991 RR and Fiber Max 991 BR. The yields for the remaining 29 varieties (P < 0.05) were increased by the application of 1,3-D as compared to the non treated controls. In north Alabama, all varieties treated with the nematicide out yielded (P < 0.05) varieties without the nematicide. The initial greenhouse evaluation of the entire TX USDA germplasm collection for resistance to the reniform nematode is complete. Preliminary analysis of the data indicates a consistent trend between the number of vermiforms and eggs recovered at 60 days after planting. We are currently selecting those genotypes with the lowest R. reniformis numbers and fewest eggs produced for a second screening. In 2005, we will reevaluate those genotypes with the lowest number of vermiforms and eggs from the initial screening. MS - Two studies were initiated in 2004: screening cotton germplasm and breeding lines for resistance to the reniform nematode, a cooperative project with the cotton breeder located at Mississippi State University to evaluate early crosses for possible nematode resistance, and establish a reniform nursery to screen advanced breeding lines across the southeast cotton belt. One preliminary study indicated that all entries were significantly less susceptible to the standard PM 1218 based on reproductive factors. NC - Work continued on identification and characterization of cotton tolerance to the Columbia lance (Hoplolaimus columbus) and sting (Belonolaimus longicaudatus) nematodes. Two experiments were conducted in 2004 with six transgenic cotton cultivars. Thus far, tolerance to H. columbus does not appear to be related to tolerance to B. longicaudatus (Koenning and Bowman). TX - In the efforts to introgress resistance to the reniform nematode from G. barbadense into G. hirsutum, eight F5 families were screened for resistance to R. reniformis. Resistance appeared to be a fixed trait in four families and still segregating in four families. Selected resistant plants had poor fertility, apparently due to low pollen viability, thus these plants have been backcrossed to the M. incognita resistant G. hirsutum line M315. USDA, GA - Dr. Davis is collaborating with Dr. O. Lloyd May (Univ. of Georgia, Tifton, GA) in developing cotton genotypes with a high-level of resistance to the southern root-knot nematode, M. incognita. This is being accomplished through a multiple backcross breeding program in a greenhouse. The highly-resistant but agronomically unacceptable germplasm M-120 and M-155 were crossed with the elite breeding line PD94042, the resulting hybrids were back-crossed to PD94042 three times, and then the plants were self-pollinated so that some plants would be homozygous for the nematode resistance genes. The most nematode-resistant plants were selected at each stage of the process for use in the next generation. They will verify that nematode resistance is not segregating (resistance genes are homozygous) and begin field selection for agronomic characteristics in 2005. Root galling in these plants is reduced by about 80-90%, though egg production has not been measured. This work should result in a cultivar release. Soybean: AR - 194 lines of soybean new to the Arkansas Soybean Variety Testing Program in 2004 were evaluated for reniform nematode reproduction. Also, reniform reproduction indices were calculated for 34 Clemson Breeding lines of E. R. Shipe and 8 breeding lines of the Arkansas Breeding Program of P. Chen. In the reniform test, 183 of 194 lines had significantly more reproduction than Forrest, a resistant check; whereas, 189 lines, including Forrest, had more reproduction than the resistant Hartwig. Of the 34 Clemson breeding lines 22 reproduced more than on Forrest, while 33 reproduced more than on Hartwig. All of the 8 Arkansas breeding lines reproduced more than both Forrest and Hartwig. A total of 285 new or recently released commercial soybean cultivars were screened for resistance to Meloidogyne incognita and for several races of Heterodera glycines in greenhouse tests. The soybean cultivars represented a range of maturity from early maturity group (MG) IV to late MG V. While there was a range in the susceptibility of the soybean cultivars to H. glycines, as indicated by their relative reproductive rates in relation to the susceptible standard, very few cultivars were resistant to any of the races tested. The results of this study are rather disappointing because it appears that while new soybean cultivars are forthcoming in abundance, very few of them hold promise for growers with severe soybean cyst nematode problems. Many of the cultivars were ranked as moderately resistant or moderately susceptible in this experiment, which may be an indication that some cultivars might perform slightly better under nematode pressure. However, greenhouse tests are probably not sufficient to be used to advise growers of possible utility of some of these cultivars under full season field conditions. Root-knot nematode resistant cultivars were also rather scarce among the cultivars tested. While a few of the early maturity group cultivars showed some promise, the majority of the cultivars with resistance to this nematode were in MG V. LA - Genomic differences in populations of the reniform nematode, Rotylenchulus reniformis, are being studied among seven populations collected from Alabama, Arkansas, Florida, Hawaii, Louisiana, Mississippi, and Texas. Analysis of genomic differences among populations is based on examination of the two intergenic spacer regions (ITS1 and ITS2) by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). Nematode genomic DNA is extracted from 10 swollen females dissected from tomato roots. A fragment with the size of approximately 1100 bp has been produced from every population. Digestion of the amplification product with a number of restriction enzymes will be followed to detect differences in RFLP banding patterns among populations. MN - A total of 59 soybean cultivars in southern Minnesota and 26 cultivars in central Minnesota were evaluated for their resistance to H. glycines in 2004. Most resistant cultivars reduced nematode egg density while susceptible cultivars increased egg density during the growing season. Several cultivars labeled as resistant supported a high population in the fields and were probably susceptible to most populations of H. glycines in Minnesota. MS - There is ongoing work screening soybean varieties for resistance to Mississippi populations of the soybean cyst nematode. NC - The identification and functional analyses of parasitism genes encoding products secreted from the esophageal gland cells of soybean cyst and root-knot nematodes has progressed. The first confirmation that the soybean cyst nematode could secrete a parasitism gene product that could mimic the function of a plant gene was obtained. The data suggested that the nematodes may augment plant cell developmental pathways for feeding and that these specific mechanisms may represent points to disrupt with parasitic interaction. It was confirmed that a nematode parasitism gene could be inhibited by a method called RNA-interference (RNAi), and that RNAi to target genes like nematode signal molecules may be expressed in plants to disrupt parasitism specifically (this could provide novel mechanisms for resistance) (E.L. Davis). Soybean populations derived from cv. Hartwig were screened for resistance to multiple races of SCN, Heterodera glycines. Three advanced lines with SCN resistance superior to cv. Fowler are currently being yield tested for potential use as cultivars. F2 populations with high levels of resistance to SCN and the herbicide Roundup are being advanced this year, and new crosses with Delsoy 5710 and herbicide resistant cultivars were made. Additionally, soybean lines derived from cvs. Anand, Fowler, and Cordell were screened for SCN resistance. The yield of 30 lines derived from Hartwig or Anand X Hartwig derived lines that have previously been selected for high levels of SCN and or reniform resistance are being yield tested this year. Anand and Fowler are resistant to race 1 of SCN (S.R. Koenning, A. Cardinal, J. W. Burton, and T. E. Carter). SC - Approximately 650 lines of soybean developed by Dr. Emerson Shipe, soybean breeder, were evaluated for resistance to races 3 and 14 of SCN. These genotypes are planted and rated as five replicates against two races and tests are sometimes repeated. SCN'resistant cultivars and breeding lines are sources of SCN resistance. Preliminary greenhouse screens are followed up by field evaluations. Initial screening begins with F2 progenies and continues with F4 progenies and experimental breeding lines. Five plants of each genotype are grown in conetainers and inoculated with 1,000 eggs of SCN. Hutcheson and Hartwig are the positive and negative controls, respectively, for race 3. Pickett and Hartwig, respectively, are the controls for race 14. Plants are grown in the greenhouse for approximately 35 days and the cysts on the roots rated according to number: 0=0, 1=1-5, 2=6-10, 3=11-20, 4=21-40, and 5=>40 (Lewis and Shipe). Field screening of elite experimental lines is done at Edisto Research & Education Center in cooperation with Dr. John Mueller. Experimental lines advanced to the USDA Regional Tests are also screened by Dr. Pat Donald (USDA-ARS). Dr. Paula Agudelo was hired on a grant written by Dr. Bruce Fortnum entitled, "Increasing effectiveness of soybean host resistance using an improved nematode identification system." She joined Dr. Lewis's lab in July 2004 as a postdoctoral researcher and is working on the feasibility of using real-time PCR to identify two of the major root-knot nematode species. Progress is being made, but it is clear that there are some fundamental problems associated with this technique when applied to Meloidogyne diagnostics. Dr. Agudelo will discuss this matter in light of her work and current review of the literature. In 2003, Dr. Emerson Shipe, soybean breeder, evaluated approximately 92 S.C. breeding lines and eight check (6 resistant, 2 susceptible) cultivars in field tests for resistance to M. arenaria, Hoplolaimus columbus, and Heterodera glycines, race 14. Plots consisted of two rows, twenty feet in length, with two replications. Fields were sampled to monitor nematode population levels. Plant vigor ratings are made sometime between R1 and R4 growth stages. Root systems are evaluated and rated for galling severity in the RKN fields. At maturity, plots are harvested and seed weights recorded. Plant response parameters from the nematode nurseries are evaluated along with seed yield from noninfested nurseries to determine which breeding lines will be advanced for further evaluation or released as cultivars. Twenty-six advanced SC breeding lines are in the 2004 USDA Southern Regional Tests. In 2003 and 2004, Dr. John Mueller conducted field nematode screening tests at Edisto REC. Popular commercially available RR® cultivars and elite SC RR® experimental lines (maturity groups VI - VIII) were planted in fields infested with SCN (race 14), M. incognita, M. arenaria (evaluated at Pee Dee REC), and Columbia lance nematode. Root gall and plant vigor ratings were taken in the root-knot fields. Plots are harvested and seed yield comparisons made. USDA, TN - Characterization of responses to resistance: Greenhouse testing of soybean varieties was done in conjunction with University of Tennessee Extension Soybean Specialist, Melvin Newman, who conducted field disease evaluations for the lines. Race 3 testing was done on 220 soybean varieties submitted by private companies and public breeders. The soybean varieties were in MG III to V. Three plants per line were inoculated with soybean cyst nematode eggs and there were three replications in time. The inoculum levels were 4,113, 3,870, and 4,331 eggs per pot for the replications in time. The Female Index was calculated for each test and averaged over the replications. Screening of germplasm in Jackson has been conducted with seven replications at one point in time. Our estimate of the standard deviation is 43.2. Variability is seen among pot replications as well as in cultures over time. This study was designed to determine the variability in SCN-plant response over time using the female index as the measured variable. Female Indices ranged from less than 1 to 136. The standard deviation of the egg population density was a linear relation between cyst count and standard deviation. Peanut: FL - Thirty-six peanut genotypes evaluated for their susceptibility to the peanut root-knot nematode showed no resistance as compared to the susceptible "Georgia Green", whereas the standard resistant variety "NemaTAM" was negative for galling. GA - Dr. Timper is collaborating with Dr. Corley Holbrook (USDA-ARS, Tifton, GA) to develop a peanut cultivar with a high level of resistance to the peanut root-knot nematode (Meloidogyne arenaria) and the Tomato Spotted Wilt Virus (TSWV). By crossing the TSWV-resistant peanut C99R with the nematode-resistant COAN, they have created a high-yielding peanut with a high level of resistance to both the nematode and the virus. This family of genotypes has been designated C724. Agronomic testing of C724 will be continued in 2005 and should result in a cultivar release. Selected crops: FL - Two root-knot nematode resistant tomato cultivars developed for Florida production had few galls as compared to the susceptible control when evaluated in autumn season. Meloidogyne mayaguensis, a new root-knot nematode species in the continental USA, was found in 11 of 26 counties sampled in Florida. The nematode has been found in agricultural fields as nurseries. OBJECTIVE 2: Development of marker-assisted selection systems for more efficient introgression of multiple resistance genes into agronomically superior crop genotypes. Cotton: TX - Efforts are under way to identify SSR markers linked to resistance to "M. incognita in the progeny of G. hirsutum m315" x G. barbadense "Tx110" . USDA, GA - Dr. Davis is collaborating with Dr. Peng Chee (Univ. of Georgia, Tifton, GA) in developing molecular markers for the genes that impart resistance to the southern root-knot nematode, M. incognita. An interspecific mapping population was created by crossing the highly-resistant Gossypium hirsutum M-120 with the susceptible G. barbedense Pima S-6. DNA was collected from 225 plants in the F2 generation on the day that the plants were evaluated for nematode resistance based on galling and egg production. The 16 most susceptible and the 16 most resistant plants were used for bulk segregation analysis. The genome was scanned with 160 RFLP markers spaced approximately 20 centimorgans apart, and 8 markers with possible links to resistance genes were identified. Further analysis utilizing DNA from the 225 individual F2 plants identified 2 markers with strong correlation to nematode resistance. Work is currently underway with more closely-spaced RFLP markers in the two regions with linkage to nematode resistance to more precisely identify the location of the resistance genes. This work is a critical step in developing molecular markers that can be used in cotton breeding. OBJECTIVE 3: Deployment of resistance and tolerance to nematodes in sustainable cropping systems. Cotton: AL - Thirty-two winter cover crops have been evaluated as potential hosts of the reniform nematode. All winter cover crops tested supported lower (P < 0.05) populations of R. reniformis compared to the cotton. Populations of R. reniformis / 500 cm3 soil on "AU Robin" crimson clover were 54% less than those on cotton, however, populations were 48% and 68% higher (P < 0.05) when compared to "Hairy" vetch and "Mt. Barker" Subterranean clover, respectively. The number of eggs produced on "AU Robin" crimson clover and "Hairy" vetch were 45% and 60% less than that of cotton but an average of 98 % higher (P < 0.05) when compared to the other cover crop treatments. Paymaster 1218, "AU Robin" crimson clover, "Hairy" vetch, and "Mt. Barker" Subterranean clover had Rf values of 15.8, 7.2, 3.7, and 2.2, respectively. The Rf values for all other cover crops averaged 0.15 compared to 0.07 for the fallow treatment. These cover crops were placed in microplots and in the field over the winter months for two years. In microplots at cover crop termination, the reniform populations were reduced an average of 68% over all cover crops and fallow treatments. In the producer's field, R. reniformis population densities were reduced 67% over all cover crop treatments. At winter cover crop termination, Rf values for each of the winter cover crop were less than 1 indicating no increase in R. reniformis over two consecutive cover cropping seasons under field conditions. The populations of R. reniformis increased through out the summer months on cotton with or without the application of aldicarb. Aldicarb reduced R. reniformis numbers and increased seed cotton yields more efficiently than any of the cover crop treatments. The highest seed cotton yields were observed in treated and untreated plots in which a leguminous cover crop had previously been grown. LA - In field trials, at the same rate and method of application of Agri-Terra, a colloidal suspension containing 1% monobasic potassium phosphate as the active ingredient, significant yield responses were observed in four consecutive years with cotton and in two of three years with soybean. In a multi-year field trial with sugarcane, the pounds of sugar per ton of cane harvested from the plant crop were numerically, but not significantly, greater than that of the non-treated control. At harvest of the first ratoon crop, however, there was a significant increase in the sugar content per ton of sugarcane. Microplot studies were conducted to determine the effects of cotton (LA 887), soybean (Pioneer 96B21), and three endemic weed species, [morning glory-MG (Ipomoea purpurea), hemp sesbania-HS (Sesbania exaltata) and Johnson grass-LG (Sorghum halepense)], on reproduction of the reniform nematode, Rotylenchulus reniformis. Treatments were arranged as a RCB design with seven replications of seven treatments: 1) cotton or soybean alone; 2) MG alone; 3) JG alone; 4) HS alone; 5) cotton or soybean co-cultured with MG; 6) cotton or soybean co-cultured with JG; and 7) cotton or soybean co-cultured with HS. Over three trials/years, the co-culture of cotton with any of the three weed species suppressed reproduction of reniform nematode significantly. Reniform reproduction data for soybean over 2 years followed a trend similar to that observed for cotton. Suppression of reniform nematode populations could have resulted either from crowding due to the increased amount of biomass present in microplots containing two plant species or from the secretion of allelopathic compounds by weed roots. Greenhouse studies were conducted to test the allelopathy hypothesis. Fifty seedlings of MG, JG or HS were transplanted into coco-fiber baskets containing 1 kg of an inert planting medium. The bottom of each basket was fitted with a 20 cm diameter plastic funnel. A piece of neoprene tubing connected the funnel bottom with a sterile, 0.5 L capacity, light-tight flask. Once each day, water was added to the baskets until the growing medium was flooded and leachate flowed into the funnels and accumulated in the flasks. These three weed leachates, control solutions (leachates from baskets containing cotton seedlings, or planting medium only) or tap water were added daily to cotton seedlings inoculated with R. reniformis and growing in 20-cm-d clay pots containing 2 Kg of steamed soil. These pots of cotton seedlings, 60 in all, represented 5 replications of 12 treatments. The first five treatments involved addition of the individual weed or control leachates to pots and the last seven treatments involved addition of tap water daily to pots containing cotton, each of the weeds separately, or each weed co-cultivated with cotton. At the conclusion of the experiment, 56 days after initiation, the numbers of reniform nematodes per pot in soil averaged 4756 for cotton; 4537, 3025 and 3207 for MG, JG and HS, respectively and 1421, 1276 and 1731 for cotton co-cultivated with MG, JG and HS. Numbers of reniform recovered from pots of cotton to which leachate from MG, JG, and HS was added averaged 109, 619 and 638 individuals, respectively. Numbers of nematodes recovered from controls were not different from those recovered from the "cotton alone" treatment. Overall, results of this experiment were almost identical with those described for the microplot environment trials with cotton and add support for the allelopathy hypothesis. This experiment is being repeated and a similar series will be established using soybean as the host plant species. Populations of R. reniformis from Louisiana, Mississippi, Arkansas, Texas and Hawaii have been used in these studies to evaluate the relative influence of egg production and viability on the rate of population growth. Over the course of two preliminary trials, hatch of eggs of reniform nematode isolates from 10 major cotton-producing parishes of LA were determined in soil and in water. In the first trial, the percent egg hatch in water and soil, respectively, averaged 90% and 93% for the Catahoula parish isolate and 58% and 45% for the Avoyelles isolate. In trial two, the Opelousas isolate had the highest percent egg hatch, which was 91% in water and 94% in soil. The Evangeline isolate had the lowest percent egg hatch in water, which averaged 58% . In subsequent trials, hatch of eggs of R. reniformis was evaluated using incubators maintained at temperatures of 23, 28 and 32C. One hundred freshly harvested eggs that were past the 8-cell but not yet at the juvenile stage of development were hand-picked using a micropipette and placed in sterile soil. Averaged over 3 trials, each with 10 replications for each population, the percent hatch at 23C ranged from 44% for the TX population to 93% for the HI population. At 28C, egg hatch ranged from 51% for the AR population to 90% for the HI population. Hatch at 32C was greatest, 91 and 93% respectively, for the LA and HI populations and least, 61%, for the AR population and 62% for the TX population. NC - An experiment concerning cotton rotation with corn, root-knot resistant soybean, and susceptible soybean was established in Lenoir Co. in 2002 and continued in 2004. The field is infested with the southern root-knot nematode Meloidogyne incognita. This experiment is designed to have root-knot resistant and susceptible cultivars and run through 2009. Cotton grown in rotation with soybean yielded more than continuous cotton in both 2003 and 2004. Cotton cultivar ST 5599BR yielded 20% more than FM989BR in when cotton was grown continuously in this rotation, but final root-knot population densities on the two cultivars did not differ suggesting that ST5599BR may have some tolerance (Koenning, and Edmisten). USDA, GA - The cumulative, multi-year effect of growing a cotton cultivar with a moderate level of resistance to M. incognita is being determined in an ongoing field experiment. Moderate resistance reduced nematode levels by about 50% after one year, but levels were still above the action threshold. Growing cotton with moderate resistance for two years resulted in root galling that was significantly lower than on susceptible cotton and nematode levels that were below the action threshold and approximately 25% of the level following susceptible cotton. There is a cumulative effect from growing moderately-resistant cotton that may provide a small benefit after one year but a much larger benefit after two or more years. Plants with nematode resistance reduce the amount of nematode reproduction that occurs, and plants with tolerance suffer less damage when parasitized by nematodes. Nematode resistance and tolerance in plants are not always linked and can occur independently of each other. Our objective was to determine if there is a relationship between resistance and tolerance in cotton. Reproduction of M. incognita was evaluated on 17 breeding lines in two greenhouse trials; a susceptible variety and a highly resistant germplasm were included for comparison. Yield was determined in 2001 and 2002 in fumigated and non-fumigated plots in a field infested with M. incognita. The amount of yield suppression caused by nematode infection differed among genotypes. Regression analysis showed that yield suppression decreased as nematode resistance increased, which indicates that tolerance in these breeding lines was largely a result of resistance, and that even moderate levels of resistance can reduce the damage caused by the nematode. Currently-available cotton cultivars support significant reproduction of the southern root-knot nematode (M. incognita), but they have not been evaluated for differing levels of yield suppression (tolerance). The objective of this study was to evaluate a collection of cotton cultivars that are susceptible to M. incognita to determine if some cultivars are more tolerant than others of parasitism by this nematode. The percentage yield suppression caused by M. incognita differed among cotton genotypes and yield suppression ranged from 18.0% to 47.3% in 2002 and from 8.5% to 35.7% in 2003. Though significant levels of tolerance were measured in our study, two years of data on percentage yield suppression document that tolerance is not consistently related to specific cultivars in the absence of nematode resistance. Regression analysis based on the two years of field data revealed a relationship in which percentage yield suppression increased linearly as yield potential increased. It appears unlikely that cotton cultivar selection for tolerance to M. incognita can be utilized to minimize yield suppression. Unfortunately, increasing yield potential increases the percentage yield suppression in cotton caused by M. incognita. Therefore, because the absolute and percentage losses to nematodes increase as yield potential increases, nematode management becomes increasingly important and beneficial. MS - New Technique. Ongoing projects include estimation of population numbers of plant-parasitic nematodes on cotton using hyperspectral imagery and reniform nematode management with VRT equipment and site-specific applications. Soybean: MN - Four-year experiments were initiated in 2002 at three field sites in Minnesota to evaluate the cover crops alfalfa, red clover, and perennial ryegrass inter-seeded with soybean for their effects on the soybean cyst nematode Heterodera glycines and soybean and corn yields in the soybean/corn annual rotation production system. Data obtained in 2002-2003 demonstrated that red clover and alfalfa reduced the nematode population density as compared with no-cover-crop control. Hirsutella rhossiliensis and Hirsutella minnesotensis are two fungal parasites of second-stage juveniles of H. glycines. The potential of liquid cultures of the two fungi in control of H. glycines was evaluated in two greenhouse experiments. Both fungi at 0.2, 0.4 and 0.8 g of fresh mycelium/300 cm3 soil were effective in control of the nematode. Soils collected from two fields that have been in long-term soybean monoculture and one field that has been in corn/soybean annual rotation were evaluated for their degree of suppressiveness to H. glycines. The soils from the monoculture fields were more suppressive than the soil from the corn/soybean rotation. Hirsutella rhossiliensis was observed in all three soils, and it parasitized a high percentage of second-stage juveniles of H. glycines in the monoculture soils. The fungus may be a major factor for the suppression of the nematode population, but other biological factors cannot be ruled out in the study. NC - Experiments with treated municipal sewer sludge for management of root-knot and soybean cyst nematode were established in 2002 and continued in 2004. A third project that focuses on the value of resistance to SCN was continued in Lenoir County. A new study focusing on blends of SCN resistant and susceptible soybean cultivars for management of H. glycines was initiated in 2004. Resistant cultivars used are Delsoy 5710, Anand and Fowler. TN - Experiments were continued to determine the effect of Monarda didyma (bee balm) amendments on hatch and infectivity of southern root-knot nematode, Meloidogyne incognita. Egg hatch was enhanced with increasing amendment fraction, but root galling was reduced significantly at the higher amendment levels. Gall number divided by hatched juvenile number provided a estimate of fitness: 0.37 for treatments without amendment (37% of hatched juveniles successfully formed galls), 0.10 for the highest treatment (only 10% of hatched juveniles formed galls. Bee balm itself was a poor host for M. incognita, with moderate nematode invasion but very poor reproduction. USDA, TN - A study on the impact of SCN reproduction during the non crop period was initiated to determine if winter annual weeds should be removed from fields and whether cover crop planting of SCN host plants posed a threat to crop production management of SCN. The effect of cover crops and winter annual weeds on SCN reproduction has been research in TN for three years. The field studied most intensively is a race 14 field located in Jackson, TN. Two other fields, one located at Milan Experiment Station and one located in Middle TN are also part of this study. Winter annual weeds and cover crop roots were examined for presence of SCN monthly throughout the non soybean crop production period. SCN life stages were recorded. Adult males or females were not present in any of the root samples over the three year time period. Cover crops (wheat and crimson clover) had no effect on SCN reproduction despite crimson clover being a host for SCN. At the two other TN locations, crop rotations included corn, cotton, and soybean and the winter treatments were canola, hairy vetch, poultry litter, wheat and fallow. Differences in SCN population density were seen in presence of soybean in the rotation, the number of years away from soybeans, and winter treatment. The highest SCN population density was continuous soybean; the lowest was in the continuous cotton and continuous corn. Poultry litter treatment samples were several orders of magnitude lower in SCN eggs than other fall treatments. Selected Crops: USDA, SC - Southern root-knot nematodes (Meloidogyne incognita) significantly reduce production of bell pepper (Capsicum annuum L.) in the U.S. and worldwide. Pre-plant soil fumigation with methyl bromide is currently used to control root-knot nematodes in peppers. However, methyl bromide use is being restricted due to its negative effects on atmospheric ozone. We studied the utility of resistant cultivars for managing root-knot nematodes in bell peppers in the Southeastern U.S. Resistance of two bell pepper cultivars, Charleston Belle and Keystone Resistant Giant, which are near-isogenic for the N gene that conditions resistance to M. incognita was evaluated in field tests in South Carolina, Georgia, and Florida. Charleston Belle (NN) was highly resistant; root galling was minimal at all test sites. Keystone Resistant Giant (nn) was highly susceptible; root galling was severe in all tests. Reproduction of M. incognita was 64% to 99% less (P< 0.05) on "Charleston Belle" than "Keystone Resistant Giant". "Charleston Belle" produced 35% (P< 0.05) and 50% (P< 0.0006) heavier fruit yields than "Keystone Resistant Giant" in Blackville, SC and Citra, FL, respectively. VA - Five isolates of plant growth promoting rhizobacteria (PGPRs) and four combinations of these isolates were compared with standard soil fumigants and aldicarb for control of tobacco cyst nematodes (Globodera tabacum solanacearum) in 2004. No PGPR isolates or combinations of isolates were associated with improved control of tobacco cyst nematodes at mid-season. Induction of systemic acquired resistance (SAR) by use of acibenzolar-S-methyl (ASM) in the field also did not reduce mid-season population densities of G. t. solanacearum. Parasitism by G. t. solanacearum was significantly lower on flue-cured tobacco lines containing the Ph gene, and on several breeding lines with partial resistance to Meloidogyne arenaria, compared to susceptible flue-cured tobacco cultivars.

AL Publications: Palmateer A.J., K. S. Lawrence, E. van Santen, and G. Morgan-Jones. 2004. Interaction of Rotylenchulus reniformis with seedling disease pathogens of cotton. Journal of Nematology 36: 160-166. Diez, Asdrubal, G. W. Lawrence and K. S. Lawrence. 2003. Nematode post-infection development on cotton following separate and concomitant parasitism by Meloidogyne incognita and Rotylenchulus reniformis. Journal of Nematology 35: 422-429. Lawrence, Kathy S., Yucheng Feng, Gary W. Lawrence, Charlie H. Burmester, and Shannon H. Norwood. 2004. Microbial Degradation of Aldicarb in Reniform Nematode Infested Cotton Field Soils. (online) Proceedings of the National Beltwide Cotton Conference Vol. 1: 395-396 (2004) National Cotton Council, Memphis TN. Jones, Jarrod R. and Kathy S. Lawrence. 2004. Greenhouse and Field Evaluations of Selected Winter Cover Crops for Reniform Nematode Suppression in Cotton. (online) Proceedings of the National Beltwide Cotton Conference Vol. 1: 397  399 (2004) National Cotton Council, Memphis TN. Usery, Stan Jr., Kathy S. Lawrence, Charles Burmester, Kathy Glass, Gary W. Lawrence, Randy Akridge, and Brad Meyer. 2004. Response of Selected Cotton Varieties to the Reniform Nematode in Alabama. (online) Proceedings of the National Beltwide Cotton Conference Vol. 1: 403-409 (2004) National Cotton Council, Memphis TN. Lawrence, G. W., A. Kelley, H. K. Lee, K. S. Lawrence. 2004. Evaluation of Adage 5FS for control of Rotylenchulus reniformis on cotton in the Mississippi delta, 2001. F&N Tests 59:N007. Lawrence, G. W., A. Kelley, H. K. Lee, K. S. Lawrence. 2004. Evaluation of Telone II and Vapam for management of Rotylenchulus reniformis on cotton in the Mississippi delta, 2001. F&N Tests 59:N008. Lawrence, G. W., A. Kelley, H. K. Lee, K. S. Lawrence. 2004. Evaluation of Temik 15G applied in-furrow and as a side dress for management of Rotylenchulus reniformis in the Mississippi delta, 2001. F&N Tests 59:N009. Lawrence, K. S., J. R. Jones, S. R. Usery, G. W. Lawrence, C. H. Burmester. 2004. Evaluation of biologicals for reniform nematode management in cotton in north Alabama, 2003. F&N Tests 59:N010. Lawrence, K. S., J. R. Jones, S. R. Usery, G. W. Lawrence, C. H. Burmester. 2004. Evaluation of the soil fumigants Vapam and Telone II for reniform nematode management in cotton in north Alabama, 2003. F&N Tests 59:N011. Lawrence, K. S., J. R. Jones, S. R. Usery, G. W. Lawrence, R. Akridge. 2004. Evaluation of the soil fumigants Vapam and Telone II for reniform nematode management in cotton, 2003. F&N Tests 59:N013. Lawrence, K. S., J. R. Jones, S. R. Usery, C. H. Burmester. 2004. Evaluation of Vydate C-LV for reniform nematode management in cotton in north Alabama, 2003. F&N Tests 59:N012 Lawrence, K. S., J. R. Jones, S. R. Usery, D. Moore. 2004. Evaluation of Temik 15 G side dress application for reniform nematode management in cotton in central Alabama, 2003. F&N Tests 59:N014. Lawrence, K. S., J. R. Jones, S. R. Usery, D. Moore. 2004. Evaluation of selected seed treatment fungicides for management of cotton seedling disease in central Alabama, 2003. F&N Tests 59:ST023. Usery, S. U. Jr., K. S. Lawrence, J. R. Jones, R. Akridge, K. Glass, G. W. Lawrence. 2004 Cotton variety response to Rotylenchulus reniformis in Huxford, Alabama, 2003. B&C Tests 19:FC018. Usery, S. U. Jr., K. S. Lawrence, J. R. Jones, C. H. Burmester, B.A. Meyer. 2004. Transgenic cotton variety response to Rotylenchulus reniformis in Lawrence Co. AL, 2003. B&C Tests 19:FC019. Usery, S. U. Jr., K. S. Lawrence, J. R. Jones, C. H. Burmester, G. W. Lawrence. 2004. Transgenic cotton variety response to Rotylenchulus reniformis in North Alabama, 2003 B&C Tests 19:FC020. Usery, S. U. Jr., K. S. Lawrence, J. R. Jones, C. H. Burmester, B. A. Meyer. 2004. Transgenic cotton variety response to Rotylenchulus reniformis in a corn cotton rotation in North Alabama, 2003. B&C Tests 19:FC017. FL Publications: Thomas, J. E., L.-T. Ou, L. H. Allen, Jr., L. A. McCormack, J. C. Vu, and D. W. Dickson. 2004. Persistence, distribution and emission of Telone C35 injected into a Florida sandy soil as affected by moisture, organic matter, and plastic film cover. Journal of Environmental Science and Health Part BPesticides, Food Contaminants, and Agricultural Wastes B39:505-516. Thomas, J. E., L. H. Allen, Jr., L. A. McCormack, J. C. Vu, D. W. Dickson, and L.-T. Ou. 2004. Atmospheric volatilization and distribution of (Z)- and (E)-1,3-dichloropropene in field beds with and without plastic covers. Journal of Environmental Science and Health Part BPesticides, Food Contaminants and Agricultural Wastes B39:709-723. Brito, J. A., T. Powers, P. G. Mullin, R. N. Inserra, and D. W. Dickson. 2004. Morphological and molecular characterization of Meloidogyne mayaguensis isolates from Florida. Journal of Nematology 36:232-240. Cetintas, R., and D. W. Dickson. 2004. Persistence and suppressiveness of Pasteuria penetrans to Meloidogyne arenaria race 1. Journal of Nematology (in press). Schmitt, L. M., J. F. Preston, G. Nong, D. W. Dickson, and H. C. Aldrich. 2004. Detection of Pasteuria penetrans infection in Meloidogyne arenaria race 1 in planta by polymerase chain reaction (PCR). FEMS Microbiology Ecology. 48:457-464. Kokalis-Burelle, N., and D. W. Dickson. 2004. Evaluation of Plantpro 45 and Plantpro 20EC as alternatives to methyl bromide soil fumigation for tomato production in Florida. Nematropica 33:171-178. Walia, R. K., T. E. Hewlett, and D. W. Dickson. 2004. Microwave treatment of Pasteuria penetrans parasite preparation for selective elimination of undesired microorganisms. Nematologia Mediterranea 32:15-17. LA Publications: McGawley, E.C., M.J. Pontif and J.B. Sumner. 2004. Efficacy of Agri-Terra against phytoparasitic nematode species indigenous to Louisiana. Pp. 138-141 In: Proceedings of the Fifth International Conference on Alternatives to Methyl Bromide, 27-30 September, 2004,Lisbon, Portugal. Carter-Wientjes, C.H., J.S. Russin, D.J. Boethel, J.L. Griffin, and E.C. McGawley. 2004. Feeding and maturation by soybean looper (Lepidoptera: Noctuidae) larvae on soybean affected by weed, fungus, and nematode pests. Journal of Economic Entomology 97:14-20. Li, Y. and E. C. McGawley. 2004. Variation in populations of Rotylenchulus reniformis in the southern U.S.A. Abstracts of the 2004 Annual Meeting of the Organization of Nematologists of Tropical America. p. 63 (O-23). McGawley, E. C. and M. J. Potif. 2004. Chemical management of nematodes in Louisiana: 2000-2003 field and microplot trials with cotton, soybean, sugarcane, rice and assorted vegetables. Abstracts of the 2004 Annual Meeting of the Organization of Nematologists of Tropical America. p. 65-66 (O-27). Pontif, M. J. and E. C. McGawley. 2004. Impact of three weed species on reproduction of Rotylenchulus reniformis on cotton and soybean. Abstracts of the 2004 Annual Meeting of the Organization of Nematologists of Tropical America. p. 68-69 (O-32). Sumner, J. B. and E. C. McGawley. 2004. Influence of egg biology on reproduction of Rotylenchulus reniformis isolates from the southern U. S. A. Abstracts of the 2004 Annual Meeting of the Organization of Nematologists of Tropical America. p. 76 (O-46). Overstreet, C., M. Wolcott, E. C. McGawley, B. Padgett, G. Burris, and D. Sullivan. 2004. Limitations of soil bulk electrical conductivity and nematode management zones. Abstracts of the 2004 Annual Meeting of the Organization of Nematologists of Tropical America. p. 66-67 (O-29). McGawley, E. C., M. J. Pontif, J. W. Hoy. 2004. Chemical management of nematodes in Louisiana: 20000-2002 filed and microplot trials with cotton, soybean, sugarcane, rice and assorted vegetables. p. 55. In: Proceedings of the 15th International Plant Protection Congress, 11-16 May, 2004, Beijing, China. MN Publications: Chen, S., and X. Liu. 2004. Control of the soybean cyst nematode by the fungi Hirsutella rhossiliensis and Hirsutella minnesotensis in greenhouse studies. Biological Control (in press). Li, Y., S. Chen, and N. D. Young. 2004. Effect of the rhg1 gene on penetration, development and reproduction of Heterodera glycines race 3. Nematology 6: (in press). Chen, S. Y., and D. W. Dickson. 2004. Biological control of nematodes by fungal antagonists. Pp. 979-1039. in Z. X. Chen, S. Y. Chen, and D. W. Dickson, eds. Nematology, advances and perspectives. Vol. II: Nematode management and utilization. Cambridge, MA: Tsinghua University Press and CABI Publishing. Niblack, T. L., and S. Y. Chen. 2004. Cropping systems. Pp. 181-206. in D. P. Schmitt, J. A. Wrather, and R. D. Riggs, eds. Biology and management of the soybean cyst nematode. Marceline, MO: Schmitt & Associates of Marceline. Chen, S. Y. 2004. Management with biological methods. Pp. 207-242. in D. P. Schmitt, J. A. Wrather, and R. D. Riggs, eds. Biology and management of the soybean cyst nematode. Marceline, MO: Schmitt & Associates of Marceline. Chen, Z. X., S. Y. Chen, and D. W. Dickson (eds.). 2004a. Nematology: Advances and perspectives. Volume 2. Nematode management and utilization. Cambridge, MA: Tsinghua University Press and CABI Publishing. 656 pages. Chen, Z. X., S. Y. Chen, and D. W. Dickson (eds.). 2004b. Nematology: Advances and perspectives. Volume I. Nematode morphology, physiology, and ecology. Cambridge, MA: Tsinghua University Press and CABI Publishing. 608 pages. Chen, S. Y., and F. J. Chen. 2003. Fungal parasitism of Heterodera glycines eggs as influenced by egg age and pre-colonization of cysts by other fungi. Journal of Nematology 35:271-277. MS Publications: Ellis, G. R., G. W. Lawrence, S. Samson, W. A. Givens, and K. S. Lawrence. 2004. Variable rate nematicide application on cotton for reniform nematode management. Journal of Nematology (In Press). Lawrence, K. S., F. Yucheng, G. W. Lawrence, C. H. Burmester, and S. H. Norwood. 2004. Accelerated biodegradation of aldicarb and its metabolites in cotton field soils. Journal of Nematology (In Press). Lawrence, G. W. and K. S. Lawrence. 2004. Effect of Visible, a soil additive, on the growth of cotton in a reniform nematode infested field. Journal of Nematology (In Press). Usery, Jr., S. R., K. S. Lawrence, C. H. Burmester, K. Glass, R. Akridge, B. A. Meyer, and G. W. Lawrence. 2004. Cotton variety response to Rotylenchulus reniformis in Alabama. Journal of Nematology (In Press). NC Publications: Gao, B., Allen, R., Davis, E.L., Baum, T. J., and Hussey, R. S. 2004. Developmental expression and biochemical properties of a ß-1,4-endoglucanase family in the soybean cyst nematode, Heterodera glycines. Molecular Plant Pathology 5:93-104. Guimaraes, P.M., Leal-Bertioli, S.C.M., Curtis, R.H., Davis, E.L., and Bertioli, D.J. 2003. Isolation of two cDNAs encoding a tropomyosin and an intermediate filament protein from the soybean cyst nematode, Heterodera glycines. Nematropica 33:87-95. Huang, G., Dong, R., Maier, T., Allen, R., Davis, E.L., Baum, T.J., and Hussey, R.S. 2004. Use of solid-phase subtractive hybridization for the identification of parasitism gene candidates from the root-knot nematode Meloidogyne incognita. Molecular Plant Pathology 5:217-222. Koenning, S. R., T. L. Kirkpatrick, J. L. Starr, J. A. Wrather, N. A. Walker, and J. D. Mueller. 2004. Plant-parasitic nematodes attacking cotton in the US: old and emerging production challenges. Plant Disease 88:100-113. Koenning, S. R. 2004. Resistance of soybean cultivars to field populations of Heterodera glycines in North Carolina. Plant Disease 88:942-950. Mitchum, M. G., Sukno, S., Wang, X., Shani, Z., Tsabary, G., Shoseyov, O., and Davis, E.L. 2004. The promoter of the Arabidopsis thaliana Cel1 endo-1,4-ß glucanase gene is differentially expressed in plant feeding cells induced by root-knot and cyst nematodes. Molecular Plant Pathology 5:175-181. Barker, K. R., S. R. Koenning, and D. P. Schmitt 2004. Population density based management. Pp. 89-110. In D.P. Schmitt, J.A. Wrather, and R.D. Riggs eds. Soybean Cyst Nematode, Biology and Management. Schmitt and Associates of Marceline: Marceline, MO. Baum, T.J., R.S. Hussey, and E.L. Davis. 2004. Parasitism gene discovery in sedentary phytonematodes. In Nematology Monographs and Perspectives, 2004, Vol. 2, pp 581-588. Koninklijke Brill NV, Leiden. Davis, E.L., R.S. Hussey, and T.J. Baum. 2004. Getting to the roots of parasitism by nematodes. Trends in Parasitology 20 (3):134-141. Davis, E.L. 2004. Diseases/Nematodes: Parasitism Genes. Pp. 793-796 In: Goodman, R.M., ed. Encyclopedia of Plant & Crop Science, Marcel Dekker, NY. Hussey R.S. and Davis E.L. 2004. Nematode esophageal glands and plant parasitism. In Nematology, Advances and Perspectives, Vol. 1 - Nematode Morphology, Physiology, and Ecology. CAB International, UK. Koenning, S. R. 2004. Population biology. Pp. 73-88. In D.P. Schmitt, J.A. Wrather, and R.D. Riggs eds. Biology and Management of Soybean Cyst Nematode, Second Edition. Schmitt and Associates of Marceline: Marceline, MO. Smant, G., E.L. Davis, R.S. Hussey, T.J. Baum, M.N. Rosso, J. Bakker, and J. Helder. 2004. On the evolution of parasitism genes. In Nematology Monographs and Perspectives, 2004, Vol. 2, pp 573-579. Koninklijke Brill NV, Leiden SC Publications: Shipe, E.R., J.D. Mueller, and S.A. Lewis. 2004. Roundup Ready Soybean Varieties for South Carolina. Proceedings of the 2004 AG EXPO, Feb. 10. Columbia, SC. Shipe, E.R., J.D. Mueller, S.A. Lewis, P.F. Williams, Jr., and R.K. Stephens. 2003. Registration of 'Santee' soybean. Crop Science 43:2305-2306. Lewis, S. A., D. J. Chitwood, and E. C. McGawley. 2004. Nematode, Biology, Morphology, and Physiology in Encyclopedia of Plant and Crop Science. Marcel Dekker, Inc., New York, NY. Perez, E. E., J. D. Mueller, and S. A. Lewis. 2003 (Published mid-2004). Seasonal population densities of Hoplolaimus columbus and their impact on soybean yield. Nematropica 33:197-207. TN Publications: Eisenback, J. D., E. C. Bernard, J. L. Starr, T. A. Lee, Jr., and E. K, Tomaszewski. 2003 (published 2004). Meloidogyne haplanaria n. sp. (Nematoda: Meloidogynidae), a root-knot nematode parasitizing peanut in Texas. Journal of Nematology 35:395-403. USDA, GA Publications: Timper, P., C.C. Holbrook, & W.F. Anderson. 2003. Reproduction of Meloidogyne spp. on resistant peanut genotypes from three breeding programs. Journal of Nematology 35:417-421. Holbrook, C.C., P. Timper, & A.K. Culbreath. 2003. Resistance to tomato spotted wilt virus and root-knot nematode in peanut interspecific breeding lines. Crop Science 43:1109-1113. Davis, R. F., and O. L. May. 2003. Relationships between tolerance and resistance to Meloidogyne incognita in cotton. Journal of Nematology 35:411-416. May, O. L., R. F. Davis, and S. H. Baker. 2004. Registration of GA96-211 upland cotton germplasm line. Crop Science 44:700-701. Thies, J. A., R. F. Davis, J. D. Mueller, R. L. Fery, D. B. Langston, and G. Miller. 2004. Double-cropping cucumbers and squash after resistant bell pepper for root-knot nematode management. Plant Disease 88:589-593. USDA, SC Publications: Levi A., C.E. Thomas, J.A. Thies, A.M. Simmons, and A.P. Keinath. 2004. Notice of release of USVL-200, A Novel Watermelon Breeding Line. USDA, Agricultural Research Service, Cultivar Release. Levi, A., C.E. Thomas, J.A. Thies, A.M. Simmons, Y. Xu, X. Zhang, O.U.K. Reddy, A.R. Davis, and T. Wehner. 2004. Developing a genetic linkage map for watermelon: polymorphism, segregation and distribution of markers. Progress in Cucurbit Genetics and Breeding Research. A. Lebeda and H.S. Paris (Eds.). p. 515-523. Thies, J.A., R.F. Davis, J.D. Mueller, R.L. Fery, D.B. Langston, and G. Miller. 2004. Double-cropping cucumbers and squash after resistant bell pepper for root-knot nematode management. Plant Disease 88(6):589-593. Thies, J.A., R.L. Fery, J.D. Mueller, G. Miller, and J. Varne. 2003. Response of bell pepper cultivars near-isogenic for the N gene to Meloidogyne incognita in field trials. HortScience 38(7):1394-1396. Thies, J.A., and A. Levi. 2003. Resistance of watermelon germplasm to the peanut root-knot nematode (Meloidogyne arenaria race 1). HortScience. 38(7):1417-1421. VA Publications: Johnson, C. S., Way, J. A., and Barker, K. R. 2004. Nematode parasites of tobacco. In: Luc, M., R. A. Sikora, and J. Bridge (eds). Plant Parasitic Nematodes in Subtropical and Tropical Agriculture. CABI Publishing, Wallingford, Oxford, UK (In press). Syracuse, A. J., Johnson, C. S., Eisenback, J. D., Nessler, C. L., and Smith, E. P. 2004. Intraspecific variability within Globodera tabacum solanacearum using random amplified polymorphic DNA. Journal of Nematology 36: (In press). Johnson, C. S. 2004. Host resistance for control of tobacco cyst nematodes in flue-cured tobacco in Virginia, 2003. B&C Tests 19:FC006. Johnson, C. S. 2004. Relative efficacy of various nematicides against tobacco cyst nematodes in Virginia, 2003. F&N Tests 59:N001. Johnson, C. S. 2004. Host resistance and use of Telone products to control tobacco cyst nematodes in Virginia, 2003. F&N Tests 59:N002. Johnson, C. S., and Clarke, C. T. 2004. Host resistance and nematicides to control tobacco cyst nematodes in Virginia, 2003. F&N Tests 59:N003. Johnson, C. S., and Clarke, C. T. 2004. Host resistance and two rates of Telone C-17 to control tobacco cyst nematodes in Virginia, 2003. F&N Tests 59:N004. Johnson, C. S., and Clarke, C. T. 2004. Host resistance and Telone C-17 for control of tobacco cyst nematodes in Virginia, 2003. F&N Tests 59:N005.