OLD S1083: Ecological and genetic diversity of soilborne pathogens and indigenous microflora

(Multistate Research Project)

Status: Inactive/Terminating

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SAES-422 Reports

Annual/Termination Reports:

[10/26/2020] [12/02/2021] [01/08/2020] [09/03/2019] [12/07/2022]

Date of Annual Report: 10/26/2020

Report Information

Annual Meeting Dates: 09/08/2020 - 09/08/2020
Period the Report Covers: 10/01/2019 - 09/30/2020

Participants

Brief Summary of Minutes

Minutes Attachment:

AnnualReport_2020_S1083 final.docx

Accomplishments

Publications

Impact Statements

Date of Annual Report: 12/02/2021

Report Information

Annual Meeting Dates: 10/05/2021 - 10/05/2021
Period the Report Covers: 10/01/2020 - 09/30/2021

Participants

Dr. Nathan Slaton (Administrative Advisor), University of Arkansas
Dr. Sydney Everhart (Secretary), University of Connecticut
Dr. William Kingery, Mississippi State University
Dr. Alejandro Rojas, University of Arkansas
Dr. Terry Spurlock, University of Arkansas
Dr. Sean Sabanadzovic, Mississippi State University
Dr. Nina Aboughanem, Mississippi State University
Dr. Soledad Benitez Ponce, The Ohio State University
Dr. Rachel Koch Bach, University of Connecticut
Dr. Sharifa Crandall, Pennsylvania State University
Dr. Shankar Ganapathi Shanmugam (Chair), Mississippi State University
Dr. Fulya Baysal-Gurel, Tennessee State University
Dr.Richard Baird, Mississippi State University

Participants Attachment:

Annual Report-S1083-2021.docx

Brief Summary of Minutes

The S1083 2020-2021 meeting was held on October 05, 2021. Due to the pandemic restrictions, the group met virtually through Zoom. The meeting lasted for 3 hours (10:30 am to 1:30 pm ET) and the agenda included a) Research updates b) Discussion about opportunities to collaborate, c) Brainstorming on the ingoing effort developing a review paper by the group, and d) Electing the secretary for 2022. The meeting was led by Dr. Ganapathi Shanmugam, with Dr. Sydney Everhart as secretary. All the group members actively participated and presented their research updates covering a wide area of expertise. Some of the general themes that were addressed included soil disease suppression, microbiome associated soil disease control, cover crops for soilborne disease control and virus-fungi association in soilborne diseases. Dr. Benitez Ponce initiated the discussion regarding the ongoing effort to develop a review paper as a potential outcome of this group. A follow-up meeting was planned to discuss about development and writing of a review paper, as an output from this team. Dr.Alejandro Rojas was nominated for the secretary position. He accepted the nomination, and without any other nominations, was elected as the incoming secretary for 2022. Finally, possible future meeting venues were discussed. The group planned to meet on Saturday prior to the annual meeting of the American Phyto pathological Society in Pittsburg, PA in August 6-10, 2022. Annual meeting video link https://vimeo.com/624741504/2b6b2d217d

Minutes Attachment:

S1083 - Annual Business Meeting 2021- Meeting minutes.docx

Accomplishments

Dr. Terry Spurlock, University of Arkansas, Accomplishments: Short-term outcomes: Soilborne disease incidence and severity were high in both cotton and soybean in 2021.  A wet year following a wet year in 2020, calls to farmers fields revealed seedling diseases caused by Rhizoctonia solani and Pythium spp. Phytophthora root and stem blight and aerial blight were impactful on soybean.  Taproot decline was also impactful to many growers’ fields in the southeastern portion of the state, specifically Chicot, Ashley, and Desha counties.  An increase in sudden death syndrome above previous years was also observed. Outputs:  Fields calls indicated these diseases continue to be economically impactful.  Growers and consultants were advised of management options through phone calls, text messages and post to social media (Twitter).  Training of county agents to identify the (relatively new) disease taproot decline was continued in 2021 through field training. Activities: Objective 2: Evaluate the efficacy of soil-borne disease management strategies (chemical, biorational/biological, cultural) and characterize the associations among microbial community profile, soil physicochemical properties, environmental factors, and disease suppression.  Corn - a new product brought to market by FMC was evaluated in on-farm trials as well as traditional replicated small plot research on experiment stations.  The product was determined to cause phytotoxicity in fields where corn was planted relatively early by AR standards.  Efficacy against both soilborne and foliar diseases were inconclusive. Soybean - variety tests and seed treatment and in-furrow fungicide trials continued to determine best management practices for taproot decline.  Due to severe flooding, these trials at the Southeastern Research and Extension Center near Kelso, AR were completed but damaged.  Symptoms of taproot decline were highly variable across the tests and therefore no varieties were determined to be tolerant of the disease.  Some chemistries applied as seed treatments and in-furrow continue to show limited efficacy. Cotton - numerous seed treatment fungicide trials were conducted at the Southeastern Research and Extension Center where inoculation using a virulent isolate of R. solani AG4 demonstrated some efficacy among commercial and experimental formulations of products.   Dr. Alejandro Rojas, University of Arkansas, Major goals of the project  (1) Evaluate the biology and diversity of soil-borne pathogens, associated antagonistic microorganisms, and environmental conditions in the context of the whole-system phytobiome. This objective includes traditional, metagenomics, and spatial/temporal methodologies to understand microbial community dynamics that determine soil-borne disease incidence and severity on economically important crops in the U.S.  (2) Evaluate the efficacy of soil-borne disease management strategies (chemical, biorational/biological, cultural) and characterize the associations among microbial community profile, soil physicochemical properties, environmental factors and disease suppression.  Accomplishments: The research has been focused on three main areas: evaluation of chemical and biological agents for control of soilborne pathogens, soybean seed quality issues and their management, and ecology of soilborne pathogens in horticultural and field crops. The evaluation of chemical and biological agents for control of soilborne pathogens is focused on rice.  We are conducting evaluations of chemical recommendations provided by industry to control common soilborne pathogens: Pythium spp., Rhizoctonia solani and Fusarium spp.  In rice, eight chemical treatments were evaluated including sedaxane, azoxystrobin, metalaxyl and fludioxonil individually and in different combinations.  All assays were conducted in vitro using a seed assay with the respective pathogens and in the greenhouse using seedling cup assay.  We are repeating the experiments and summarizing the findings of this research.  With respect to the development of biocontrol agents is a project in collaboration with Dr. Clemencia Rojas, and the aim is to characterize the potential biocontrol range of bacteria against rice fungal and oomycete pathogens. These bacteria were previously identified as potential biocontrol agents of rice panicle blight. The project is funded by the Arkansas Rice Promotion Board and we identified Burkholderia and Pseudomonas as a potential biocontrol agent of fungal pathogens that affect mainly rice, but also caused an impact on other field crops.  The genomes of these bacteria have been sequenced and we are focused on the characterization of these bacteria in vitro and as seed treatments.    With respect to seed quality, we have different lines of investigation that converge on a similar goal: determining the factors that drive seed quality and efficient and effective use of fungicides to control foliar pathogens. The first line is establishing a baseline sensitivity of Cercospora against several foliar fungicides, which is a proposal with Dr. Travis Faske funded by the Soybean Promotion Board. The goal is to determine the extent of resistance of Cercospora spp. and Corynespora cassiicola in the field to different chemistries now being used by growers, mainly triazoles (FRAC 3 - DMI) and Azoxystrobin (FRAC 11 – QoI). A collection of Cercospora spp. isolates was established from six counties in Arkansas, and those isolates were initially tested for resistance against Tetraconazole (DMI).  We are testing the same set of isolates against Azoxystrobin (QoI). Part of this project is also contributing to ongoing collaborations with Dr. Terry Spurlock, Dr. John Rupe, Dr. Nick Bates on understanding the role of foliar fungicides on impacting seed infection and stinkbug damage. Reduced seed quality is associated with Cercospora and Phomopsis. Seed collected from plots with different fungicide and insecticide applications were collected and evaluated for seed quality and seed infection.  In addition, in collaboration with Dr. Rupe, soybean plots with foliar fungicide treatments applied at R3, R5 and R3+R5 were evaluated and developing pods and mature seeds were collected for the detection of fungal pathogens using DNA based tools, especially those species associated with reduced seed quality.   In the area of the ecology of soilborne pathogens, we are actively working on research of Taproot decline (TRD), Xylaria necrophora in collaboration with Dr. Spurlock.  We aim to characterize how cover crops could improve or cause issues with soilborne diseases using TRD as model to understand this potential interaction. In this area, we have been working on testing cover crops as alternative hosts for this pathogen and we are working on developing molecular diagnostic methods to track this pathogen.  A field trial was established at Milo Shult Research & Extension center at Fayetteville.  The aim is to study the relation between plant infection and severity of symptoms using isolation and PCR.  The trial is arranged split design (cover crop and no cover crop) and within each split, there is randomized block design with three cultivars inoculated or non-inoculated and each treatment combination has four replications.  Each plot is 4-rows, 36 ft long and the planting rate was 6 seed/ft.  Inoculum was grown on millet, colonized material was air dried and placed with seed at 2.5 g/row-ft.  Soil samples were collected, and roots were also collected at three time points at reproductive stages.  Aerial images and SPAD measurements were also taken at each time point (July 13th, August 9th and September 13th).   Dr. Soledad Benitez Ponce, The Ohio State University  The activities performed in the Benitez Lab at The Ohio State University, as they pertain to the S1083 multistate project are described below by project objective. Research in the Benitez Lab is focused on understanding the impact of production practices, in crop health and its associated microbiome and function, with particular emphasis on corn and soybean production, and practices that promote soil health through crop diversification.  Accomplishments: Objective 1. Evaluate the biology and diversity of soil-borne pathogens, associated antagonistic microorganisms, and environmental conditions in the context of the whole-system phytobiome. This objective includes traditional, metagenomics, and spatial/temporal methodologies to understand microbial community dynamics that determine soil-borne disease incidence and severity on economically important crops in the U.S.  In 2020-2021, we continued to evaluate relationships between communities of fungi in soils and incidence of soybean cyst nematodes, across the state of Ohio. For this, during the 2021 growing season a total of 102 soil samples were collected across 19 counties. The majority of samples were from farms under a corn-soybean rotation, with 2021 being in soybean. The soil samples are currently being processed to determine SCN-egg counts, and update current distribution of SCN in Ohio. This work is in collaboration with the soybean pathology team at OSU. Counties in which SCN was previously not reported were particularly targeted in this survey. Fungal community characterization of these samples will be performed using culture-based and culture-independent approaches. From past surveys we identified that the most common fungi recovered through culturing belong to the genus Fusarium, whereas through amplicon metabarcoding we recover greater number of reads of Mortierella. Finally, a culture-independent survey of fungi associated to SCN cysts also indicates presence of Fusarium in cysts, but also other fungal species such as Exophiala sp., Talaromyces, Zygomycota, and Trichoderma sp.  Objective 2. Evaluate the efficacy of soil-borne disease management strategies (chemical, biorational/biological, cultural) and characterize the associations among microbial community profile, soil physicochemical properties, environmental factors and disease suppression. The successful application of biological control products and other microbial inoculants is often dependent on environmental variables and management practices, as complex interactions often occur in the plant-soil interface. The Benitez Lab is continuing research on beneficial fungi, with emphasis on the arbuscular mychorrizal fungi (AM). During the 2020-2021 reporting period, the work was focused on testing molecular tools to detect AM colonization in the field. For this we used samples from the 2020 field season, which were treated with AM-fungal inoculants, a conventional seed treatment (nematicide and fungicide mix) or non-treated. The two approaches tested were an amplicon-metabarcoding approach using the PacBio technology, targeting AM-specific ribosomal genes; and a commercially available synthetic long-read sequencing technology, through Loopgenomics. In addition, we used standard PCR, with published primers for different species of Glomeromycota. For the standard set of primers offered by Loopgenomics, no AM reads were detected. In addition, preferential amplification of plant material was observed, suggesting the standard primers offered by the service are not ideal for root DNA extracts. However, previous bioinformatic analysis of the primers suggested potential amplification of AM species. Like the results from Loopgenomics, successful recovery of AM reads was not observed with the protocol used for PacBio sequencing. These results contrast with some of the field colonization data, which indicate that AM colonization in untreated roots ranged between 0-25%; in seed treated roots between 25-50%, in AM-only treated between 10-35%, and in AM-treated + seed treatment between 5-65%. The next steps for this project are to continue working on a molecular protocol that can be used to monitor if the inoculant successfully colonized soybean roots, compared to native AM populations.   Dr. Sharifa Crandall, Pennsylvania State University  Intended activities: I focused my new soilborne research program at Penn State on researching several infamous fungal and oomycete plant pathogens that are a problem specifically in Pennsylvania and the North East (e.g., Fusarium, Verticillium, Rhizoctonia). I combined my own knowledge and expertise in microbial ecology and fungal pathology with what I found to be the current gaps and future directions for our discipline. I then created three large focal areas and questions for my research program: (1) disease dynamics of microbial communities: how do fungal and oomycete pathogens shape microbial community diversity, structure, and function within the root, soil, as well as host phenotype? (2) ecological interactions: how does stress drive the complex functional interactions between hosts, microbiomes, and the environment?, and (3) soil management: how can different sustainable soil farming strategies improve soil health? These are the intended areas I plan to conduct research in over the next few years.  Short-term Outcomes: I joined the advisory board of PASA - Pennsylvania Sustainable Agriculture and served on various committees to help increase the diversity of farmers and students who will join the agricultural workforce as well as helped allocate COVID-19 relief funds to farmers in my region based on need.   Dr. Shankar Ganapathi Shanmugam and Dr. William l. Kingery - Mississippi State University.  Accomplishments: Research in soil microbial ecology lab pertaining to S1083  multistate project  focused on understanding  how management practices in Mississippi soybean production systems (e.g., early-planting, precision seed placement, irrigation systems, residue management) relate to the occurrence of Soybean taproot decline (TRD) in order to verify the effects of altering management practices, and to determine the potential for enhancing the disease suppressive ability of these endemic soils. The aim is to broaden the range of cost-effective practices for TRD suppression that are amenable to incorporation into Mississippi soybean production systems.  OBJECTIVE 1: Survey of fields for TRD incidence and severity as well as distribution within agricultural fields that differ in farming system classification.  OBJECTIVE 2: Evaluation of the ecology of Xylaria spp. based on pathogen population in soil and microbiome structure and function.   Accomplishments: Objective 1:  A total of 20 soybean fields across six Delta counties were evaluated for the field-scale characteristics of symptomology of Soybean Taproot Decline. Evaluations were made at the R5 stage of crop development. A two-tier rating system for characterization was utilized. Field-scale distribution of symptoms were rated with the use of a 7-category system extending from no symptoms visible to symptomology present throughout. The categories included descriptors for symptoms appearing in concentration, i.e., clusters of infected plants, through symptoms distributed throughout the field. Fields were divided into four quarters with an overall rating given as the average of the four. Infection intensity percentage was measured by counting the number of infected plants per 100 plants in a linear section of row. This was done at two randomly chosen positions within each of the field quarters mentioned above. 158 survey transects across twenty soybean fields were conducted to rate TRD severity and distribution. Plant growth stage and residue ratings were also documented at each survey transect.  Objective 2: Two fields in the Mississippi Delta were sampled at locations within the fields that represented three ranges of Soybean Taproot Decline intensity (0%, 1-50%, and > 50% of plants infected along one linear meter of row, i.e., infection intensity grouping of low, medium an high). From each site, soil core plugs were collected along the one meter of row, to a 10-cm depth and composited. Two additional Delta fields, each with nine geo- referenced location per field were measured for percentage infection along one linear meter of row and soil sampled as described above at three dates (June, July and August). At the final sampling, all plants at each of the nine locations were collected and returned to the lab to make a final determination of Soybean Taproot Decline infection and to determine grain yield. Preliminary Results: Amplicons targeting bacterial 16S and fungal 18S rRNA genes (ITS2) were sequenced using Illumina MiSeq sequencing platform. The distribution of the 500 most abundant OTUs (operational taxonomic units) in the soil samples from the two locations indicated two primary patterns of soil bacterial community structure. The location has a significant effect on the bacterial community structure. The important part of the structural variability was related to differences associated with the sampling dates. There was no significant difference in the pattern of bacterial community structure with mid and late sampling dates (p=0.618 and 0.529, respectively) indicating that the disease severity had a significant effect on the soil bacterial community composition.     Dr. Fulya Baysal-Gurel, Tennessee State University    Major Goals and Objectives Overall Goal: Identify effective soil-borne disease management strategies for field nursery production of woody ornamentals to manage soil-borne pathogens that can be easily and readily adopted by field nursery growers. Objective 1. Evaluate the efficacy of chemical and biorational products for controlling soil-borne diseases with different application methods, intervals and reduced-rate applications in woody ornamentals. Objective 2. Develop improved soil-borne disease management strategies based on cultural approaches for suppression of Rhizoctonia and (or) Phytophthora spp. and other soil-borne pathogens. Objective 3. Characterize the associations between microbial community profile and soil-borne disease suppression expressed in different soil-borne disease management strategies. Objective 4. Engage in outreach and technology transfer with woody ornamental nursery growers. Accomplishments Evaluate the efficacy of chemical and biorational products for controlling soil-borne diseases with different application methods, intervals and reduced-rate applications in ornamentals.   The purpose of this study was to evaluate fire ant venom alkaloids and an alarm pheromone analog against several plant pathogens, including Botrytis cinerea, Fusarium oxysporum, Phytophthora nicotianae, P. cryptogea, Pseudomonas syringae, Phytopythium citrinum, Rhizoctonia solani, Sclerotonia rolfsii, Xanthomonas axonopodis, and X. campestris. All pathogens were tested against red imported fire ant venom alkaloid extract and alarm pheromone compound for growth inhibition in in vitro assay. The venom alkaloid extract inhibited fungal and oomycete pathogens. Neither of the treatments were effective against bacterial pathogens. Three soilborne pathogens, P. nicotianae, R. solani, F. oxysporum, and one foliar pathogen, B. cinerea were selected for further in-vivo assays on impatiens (Impatiens walleriana 'Super Elfin XP violet'). Total plant and root weight were higher in venom alkaloid treated plants compared to an inoculated control. The venom alkaloid treatment reduced damping-off, root rot severity, and pathogen recovery in soilborne pathogen inoculated plants. Similarly, venom alkaloid reduced Botrytis blight. However, higher venom rates caused foliar phytotoxicity on plants. Therefore, additional work is needed to evaluate rates of venom alkaloids or formulations to eliminate negative impacts on plants. Overall, these results suggest that red imported fire ant venom alkaloids may provide a basis for new products to control soilborne and foliar plant pathogens.   Develop improved soil-borne disease management strategies based on cultural approaches for suppression of Rhizoctonia and (or) Phytophthora spp. and other soil-borne pathogens.   We studied the response of the major cover crops being used by woody ornamental growers in the Southeastern United States to Phytopythium vexans, Phytophthora nicotianae, and Rhizoctonia solani in greenhouse conditions to identify the effective cover crops that can be used in a nursery field production system. Data related to post-emergence damping-off and plant growth parameters (plant height increase and fresh weight) were recorded. Similarly, cover crop roots were assessed for root rot disease severity using a scale of 0–100% roots affected. Among the tested cover crops, the grass cover crops triticale (×Triticosecale Wittm. ex A. Camus.), annual ryegrass (Lolium multiflorum L.), Japanese millet (Echinochloa esculenta (A. Braun) H. Scholz), and the legumes Austrian winter pea (Pisum sativum var. arvense (L.) Poir) and cowpea ‘Iron and Clay’ (Vigna unguiculata (L.) Walp.), showed lower root rot disease severity and post-emergence damping-off in the soil inoculated with P. nicotianae, R. solani, or P. vexans compared to the other crops. Since these cover crops can act as non-host crops and benefit the main crop in one way or another, they can be used in the production system.    Future Plans <ol> <li>Evaluate the efficacy of chemical and biorational products for controlling soil-borne diseases with different application methods, intervals and reduced-rate applications in woody ornamentals. We will continue to evaluate chemicals and biorational products for use in soil-borne disease management at greenhouse and field conditions.</li> <li>Develop improved soil-borne disease management strategies based on cultural approaches for suppression of soil-borne pathogens. We will continue to evaluate cultural approaches for use in soil-borne disease management at on-farms and on-station.</li> <li>Characterize the associations between microbial community profile and soil-borne disease suppression expressed in different soil-borne disease management strategies. Microbial community analyses will be performed on field experiment root and soil samples.</li> </ol> Dr.Richard Baird, Mississippi State University Title: Volatile Biomarkers For Early-Stage Disease Diagnosis of Sweet Potato Fungal Soft Tissue Disease Within Warehouses (Rhizopus stolonifer and Macrophomina phaseolina-Mp)   Objective: Long-term objective of this project is to develop monitoring hardware that can identify the presence of key rot pathogens in sweet potato roots from microbial volatile chemicals (MVOC’s) produced by rot pathogens. We are at later stages development of appropriate chemical and physical methodology to assess rot microbe development following harvest and during storage.               Since 2019, laboratory and incubator studies were conducted (current) to evaluate and determine chemical signatures for isolates of Mp and R. stolonifer compared to uninoculated controls. Tissues from select varieties of sweet potatoes namely, Beauregard-14 (B 14), Beauregard-63 (B 63) and Orleans were used across 3 years to investigate the fungal infection. Headspace solid phase micro-extraction method coupled with HS-SPME GC/MS was used to collect microbial volatile organic compounds produced by the pathogen isolate inoculated sweet potatoes.   Results:             HS-SPME GC-MS untargeted metabolomics work identified a set of volatile metabolites related to progression of fungal soft tissue disease on sweet potatoes, especially while in storage conditions. The OPLS-DA model identified ethyl acetate ethyl crotonate, ethyl isovalerate, and anisole as specific for the later stage of the disease while 1-menthone emissions were associated with early stages of the disease. Ethyl alcohol, 1-propanol, 3-methyl, 3-buten-1-ol, prenol and ethyl propionate were presence in the volatile profile of both of early and later stage of the disease. Therefore, based on our observations, we hypothesized that the synthesis of high ethanol content in the fungal infected sweet potatoes could lead to more VOCs, especially ethyl acetate, ethyl crotonoate and isoprenol, being produced. Even though many discriminatory biomarkers were identified, only the above 10 were confirmed as level 1 identified metabolites. OPLSDA combined with ROC analysis identified 1-propanol, ethyl alcohol, 3-70 methyl, 3-buten-1-ol and ethyl propionate as putative volatile disease markers for the fungal soft tissue disease in sweet potatoes. Additionally, we found that the R. stolonifer fungi emitted many butane derived volatiles including ketones, alcohols and esters. Overall, these findings elucidate the volatiles related to the pathogenicity of R. stolonifer on sweet potatoes.  Title: Developing a rapid and portable assay for the diagnosis of seedling diseases caused by Rhizoctonia solani using Near Infrared (NIR) Spectroscopy :Mariana Santos-Rivera, Matt Harjes, Richard Baird, and Carrie K. Vance   Objectives:             The work proposed in this SRI is expected to allow future development of an NIR-based diagnostic test that can be run at the farm in real time to diagnose the AGs from R. solani affecting crops more accurately in their roots and leaves. A cost effective and reliable diagnostic test would enable county agents and consultants to provide timely management and advice or treatment with fungicides, thus decreasing expenses resulting from inaccurate diagnosis of affected crops.   <ul> <li>Identify characteristic NIR spectral signatures from solani anastomosis groups though in-vitro experiments</li> <li>Identify characteristic NIR spectral signatures from solani anastomosis groups though in-vivo experiment</li> </ul>   Results: <ol> <li>Four multinucleate solani AG isolates were detected and discriminated that were inoculated in basal liquid cultures using NIRS, chemometrics and aquaphotomics. Biochemical changes related to differences in metabolic growth generated distinct patterns in the WAMACs and WASPs based on dominant peaks in the wavelength range 1300-1600nm where OH, CH, and NH bonds interact with NIR light.</li> </ol>             <ol start="2"> <li>NIRS data in combination with chemometrics and aquaphotomics has potential as a rapid laboratory assay for solani AGs detection and discrimination as soon as 1-day post-inoculation using liquid cultures, in comparison with the 8 days required with the traditional classification method using DNA sequence data collection. This will reduce the current detection time and the selection of an accurate treatment for a most or less destructive AGs before economic losses occur in the crops.</li> </ol>

Publications

Teddy Garcia-Aroca, Paul P. Price, Maria Tomaso-Peterson, Tom W. Allen, Tessie H. Wilkerson, Terry N. Spurlock, Travis R. Faske, Burt Bluhm, Kassie Conner, Edward Sikora, Rachel Guyer, Heather Kelly, Brooklyn M. Squiers & Vinson P. Doyle (2021) Xylaria necrophora, sp. nov., is an emerging root-associated pathogen responsible for taproot decline of soybean in the southern United States, Mycologia, 113:2, 326-347, DOI: 10.1080/00275514.2020.1846965 T.N. Spurlock, J. A. Rojas, Q. Fan, A.C. Tolbert, and R. Hoyle. 2021. Understanding Taproot Decline. Arkansas Soybean Research Studies. pp. 96 - 101. Faske, T., Smith, S., Spurlock, T., Wamishe, Y. MP154 Arkansas Plant Disease Control Products Guide. 2021.  T.N. Spurlock, A.C. Tolbert, S.F. Pennington, and R. Hoyle. 2021. Evaluation of cotton seed treatments against Rhizoctonia solani AG-4 in southeast AR, 2020. PDMR15:CF200. T.N. Spurlock, A.C. Tolbert, S.F. Pennington, and R. Hoyle.  2021. Evaluation of cotton seed treatments at two seeding rates against Rhizoctonia solani AG-4 in southeast Arkansas, 2020. PDMR15:CF201. T.N. Spurlock, A.C. Tolbert, S.F. Pennington, and R. Hoyle. 2021. Evaluation of experimental cotton seed treatments against Pythium ultimum at Kelso, Arkansas, 2020. PDMR15:CF202. T.N. Spurlock, A.C. Tolbert, S.F. Pennington, and R. Hoyle. 2021. Evaluation of cotton seed treatments against Pythium ultimum in southeast AR, 2020. PDMR15:CF204. Bradley, C. A., Allen, T. W., Sisson, A. J., Bergstrom, G. C., Bissonnette, K. M., Bond, J., Spurlock, T, et al. 2021. Soybean Yield Loss Estimates Due to Diseases in the United States and Ontario, Canada, from 2015 to 2019. Plant Health Progress. :PHP-01-21-0013-RS. Gil, J., Ortega, L., Rojas, J.A. and Rojas, C.M., 2021. Genome Sequence Resource of Burkholderia glumae UAPB13. PhytoFrontiers, (ja). Buckner, E. and Rojas, A., 2021. Baseline Sensitivity to Demethylation Inhibitors Fungicides In Cercospora spp. and Corynespora spp. in Arkansas Soybeans. Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences, 22(1), pp.8-14. Hatlen, R.J., Higgins, D.S., Venne, J., Rojas, J.A., Hausbeck, M. and Miles, T.D., First report of halo blight of hop (Humulus lupulus) caused by Diaporthe humulicola in Quebec, Canada. Plant disease. Milani, T., Hoeksema, J., Jobbágy, E., Rojas, J.A., Vilgalys, R. and Teste, F., 2021. Co-invading ectomycorrhizal fungal succession in pine-invaded mountain grasslands. Authorea Preprints. Huo D, Frey T, Lindsey L, Benitez MS. Contrasting effects of soybean-wheat-corn rotation on corn and soybean production and soil health. Submitted to: “Crop, forage and turfgrass management” (June 2021, Accepted with revisions, Oct 2021). Malacrino A; Abdelfattah A; Berg G; Benitez MS; Bennett AE; Böttner L; Xu S; Schena L. Exploring microbiomes to enhance plant health.Submitted to: Biological Control. Oct 2021. Crandall, S.G., Ramon, M. L., Burkhardt, A. K., Bello, J. C., Adair, N., Gent, D. H., Hausbeck, M. K., Quesada-Ocampo, L. M. and Martin, F. N. 2021. A multiplex TaqMan qPCR assay for detection and quantification of clade 1 and clade 2 isolates of Pseudoperonospora cubensis and P. humuli. Plant Disease. https://doi.org/10.1094/PDIS-11-20-2339-RE Crandall, S.G., Spychalla, J., Crouch, U., Acevedo, F., Naegele, and T. Miles. (In Press). Rotting grapes don't improve with age: cluster rot disease complexes, management, and future prospects. Invited: Special Feature, Plant Disease.  W.L. Kingery, Dan Prevost and Shanmugam, S.G. In-season Survey of Soybean Taproot Decline Incidence and Severity on Selected Mississippi Delta Farms. The American Phytopathological Society, Southern division  meeting, March 2021 Panth, M., Witcher, A., and Baysal-Gurel, F. 2021. Response of cover crops to Phytopythium vexans, Phytophthora nicotianae, and Rhizoctonia solani, major soilborne pathogens of woody ornamentals. Agriculture 11(8):742 DOI: <a href="http://dx.doi.org/10.3390/agriculture11080742">10.3390/agriculture11080742</a> (Baysal-Gurel-corresponding author). Yang, X., Castroagudin, V.L., Daughtrey, M., Loyd, A., Weiland, J.E., Shishkoff, N., Baysal-Gurel, F., Santamaria, L., Salgado-Salazar, C., LaMOndia, J.A., Crouch, J., Luster. D.G. 2021. A Diagnostic guide for Volutella blight affecting Buxaceae. Plant Health Progress. <a href="https://doi.org/10.1094/PHP-02-21-0052-DG">https://doi.org/10.1094/PHP-02-21-0052-DG</a>. Bika, R. and Baysal-Gurel, F.  2021. Identification of Fusarium commune, the causal agent of postharvest zinnia meltdown disease in Tennessee. HortTechnology. <a href="https://doi.org/10.21273/HORTTECH04795-21">https://doi.org/10.21273/HORTTECH04795-21</a> (Baysal-Gurel-corresponding author) Dawadi, S., Baysal-Gurel, F., Addesso K.M., Liyanapathiranage, P., and Simmons, T. 2021. Fire ant venom alkaloids: Possible control measure for soilborne and foliar plant pathogens. Pathogens. 2021, 10, 659. <a href="https://doi.org/10.3390/pathogens10060659">https://doi.org/10.3390/pathogens10060659</a> (Baysal-Gurel-corresponding author). Bika, R., Copes, W., Baysal-Gurel, F. 2021. Comparative Performance of Sanitizers in Managing Plant-to-plant Transfer and Postharvest Infection of Calonectria pseudonaviculata and Pseudonectria foliicola on Boxwood. Plant Disease. DOI: <a href="http://dx.doi.org/10.1094/PDIS-03-21-0481-RE">10.1094/PDIS-03-21-0481-RE</a>. Baysal-Gurel, F. and Bika, R. 2021. Management of powdery mildew on ninebark using sanitizers, biorational products and fungicides. HortScience. Vol 56: Issue 5 p. 532-537. <a href="https://doi.org/10.21273/HORTSCI15691-21">https://doi.org/10.21273/HORTSCI15691-21</a> (Baysal-Gurel-corresponding author). Baysal-Gurel, F., Bika, R., Avin, F.A., Jennings, C., and Simmons, T., 2021. Occurrence of Volutella Blight Caused by Pseudonectria foliicola on Boxwood in Tennessee. Plant Disease. <a href="https://doi.org/10.1094/PDIS-01-21-0109-PDN">https://doi.org/10.1094/PDIS-01-21-0109-PDN</a> (Baysal-Gurel-corresponding author). Baysal-Gurel, F., Bika, R., Jennings, C., Palmer, C., and Simmons, T. 2020. Comparative performance of chemical and biologically-based products in management of algal leaf spot on magnolia. HortTechnology. <a href="https://doi.org/10.21273/HORTTECH04692-20">https://doi.org/10.21273/HORTTECH04692-20</a>. (Baysal-Gurel-corresponding author). Bika, R., Palmer, C., Alexander, L., and Baysal-Gurel, F. 2020. Comparative performance of reduced-risk fungicides and biorational products in management of post-harvest Botrytis cinerea on hydrangea cut flowers. HortTechnology. https://doi.org/10.21273/HORTTECH04656-20. (Baysal-Gurel-corresponding author). Baysal-Gurel, F., Bika, R., Simmons, T, and Jennings, C. 2021. Evaluation of fungicides for the control of Volutella blight of boxwood, 2020. Plant Disease Management Report No. 15:OT001. Online publication. The American Phytopathological Society, St. Paul, MN. Baysal-Gurel, F., Simmons, T, and Jennings, C. 2021. Evaluation of fungicides for the control of boxwood blight, 2020. Plant Disease Management Report No. 15:OT002. Online publication. The American Phytopathological Society, St. Paul, MN. Baysal-Gurel, F., Simmons, T, and Jennings, C. 2021. Evaluation of different rates of Postiva for the control of Cercospora leaf spot, black leaf spot and powdery mildew of rose, 2020. Plant Disease Management Report No. 15:OT003. Online publication. The American Phytopathological Society, St. Paul, MN. Baysal-Gurel, F., Simmons, T, and Jennings, C. 2021. Evaluation of fungicides for control of Entomosporium leaf spot on Indian hawthorn, 2020. Plant Disease Management Report No. 15:OT004. Online publication. The American Phytopathological Society, St. Paul, MN. Baysal-Gurel, F., Simmons, T, and Jennings, C. 2021. Evaluation of fungicides for control of Cercospora leaf spot on Hydrangea, 2020. Plant Disease Management Report No. 15:OT005. Online publication. The American Phytopathological Society, St. Paul, MN. Baysal-Gurel, F., Simmons, T, and Jennings, C. 2021. Evaluation of fungicides for control of powdery mildew and spot anthracnose of dogwood, 2020. Plant Disease Management Report No. 15:OT006. Online publication. The American Phytopathological Society, St. Paul, MN. Baysal-Gurel, F., Simmons, T, and Jennings, C. 2021. Evaluation of fungicides for control of powdery mildew on crapemyrtle, 2020. Plant Disease Management Report No. 15:OT007. Online publication. The American Phytopathological Society, St. Paul, MN. Baysal-Gurel, F., Simmons, T, and Jennings, C. 2021. Evaluation of fungicides for control of powdery mildew of Hydrangea, 2020. Plant Disease Management Report No. 15:OT013. Online publication. The American Phytopathological Society, St. Paul, MN. Baysal-Gurel, F., Parajuli, M., and Panth, M. 2021. Evaluation of fungicides, biofungicides, host plant defense inducers and fertilizer for the control of Phytopythium root rot of red maple, 2020. Plant Disease Management Report No. 15:OT014. Online publication. The American Phytopathological Society, St. Paul, MN. Baysal-Gurel, F., Oksel, C., Simmons, T, and Jennings, C. 2021. Evaluation of fungicides for the control of black leaf spot of rose, 2020. Plant Disease Management Report No. 15:OT015. Online publication. The American Phytopathological Society, St. Paul, MN. Baysal-Gurel, F., Oksel, C., Simmons, T, and Jennings, C. 2021. Evaluation of bactericides for control of Pseudomonas leaf spot on Magnolia, 2020. Plant Disease Management Report No. 15:OT016. Online publication. The American Phytopathological Society, St. Paul, MN. Baysal-Gurel, F., Parajuli, M., and Panth, M. 2021. Evaluation of fungicides, biofungicides, host plant defense inducers and fertilizer for the control of Phytopythium root rot of ginkgo, 2020. Plant Disease Management Report No. 15:OT017. Online publication. The American Phytopathological Society, St. Paul, MN. Baysal-Gurel, F., Neupane, S., and Simmons, T. 2021. Evaluation of fungicides, biofungicides, host plant inducers and fertilizer for the control of Phytophthora root rot of boxwood in field conditions, 2020. Plant Disease Management Report No. 15:OT018. Online publication. The American Phytopathological Society, St. Paul, MN. Baysal-Gurel, F., and Neupane, K. 2021. Evaluation of fungicides and host plant defense inducers for the control of Phytophthora root rot of dogwood, 2020. Plant Disease Management Report No. 15:OT019. Online publication. The American Phytopathological Society, St. Paul, MN. Baysal-Gurel, F., Simmons, T, and Jennings, C. 2021. Evaluation of fungicides for control of Cercospora leaf spot on crapemyrtle, 2020. Plant Disease Management Report No. 15:OT020. Online publication. The American Phytopathological Society, St. Paul, MN.

Impact Statements

Review Paper: The group is developing a review paper to be submitted to Phytopathology journal. The tentative tile is “From farms to landscapes: Scalability and resolution of methods used to predict yield and diseases caused by soilborne pathogens”. Have had 6-7 meetings over the past year to develop this outline / document. Manuscripts addresses issues across multiple spatial scales, with case studies to highlight successful approaches used for different patho- systems.

Date of Annual Report: 01/08/2020

Report Information

Annual Meeting Dates: 12/13/2019 - 12/13/2019
Period the Report Covers: 01/01/1970 - 01/01/1970

Participants

Brief Summary of Minutes

Minutes Attachment:

S1083 Multistate project - Dec 13 2019 meeting minutes.docx

Accomplishments

Publications

Impact Statements

Date of Annual Report: 09/03/2019

Report Information

Annual Meeting Dates: 11/15/2018 - 11/15/2018
Period the Report Covers: 11/01/2017 - 09/30/2018

Participants

Brief Summary of Minutes

Minutes Attachment:

S1083 Multi-state project report - 2018.docx

Accomplishments

Publications

Impact Statements

Date of Annual Report: 12/07/2022

Report Information

Annual Meeting Dates: 11/02/2022 - 11/02/2022
Period the Report Covers: 10/01/2021 - 09/30/2022

Participants

Participants Attachment:

S1083_Agenda_BusinessMeeting_2022_minutes[30].docx

Brief Summary of Minutes

Accomplishments

Rhizoctonia zeae (Everhart) – Project focused on fungicide resistance lead by two PhD student Nikita Gambhir and Srikanth Kodati.  In vitro testing of three chemistries using isolates from corn and soybean.  No difference by host but most isolates were sensitive.  Among the chemistries, azoxystrobin was investigated further, since SHAM was not effective on controlling alternative oxidation, a greenhouse assay was conducted.  Stand counts and disease index showed that azoxystrobin did not reduce disease severity. Further analysis included population genetics using markers derived from genome sequencing.  With a set of markers there was enough resolution to divide the population and the population is mixed, which could mean a higher risk for fungicide resistance. Verticillium dahlia (Crandall) – VCG to identify populations moving from weeds and other hosts to economically important crops.  V. dahliae could serve as an endophyte in other hosts that could increase the potential for reservoir populations that increase genetic diversity.  There are two main groups VCG4A and 4B, both causing disease on potato.  Currently, Sharifa’s group is working on developing and optimizing the primers for detection of the two VCG groups.  There is also ongoing field work with different gradients of inoculation using potato and oats to determine pathogen movement and looking at microbiome component to determine the role of rotation and beneficial communities. Fusarium oxysporum (Crandall) – Another project is focused on continental movement of soilborne pathogens through a NASA grant in collaboration with Katie Gold from Cornell.  Using F. oxysporum to understand movement of spores in dust plumes and contributing to spread of major diseases.  The questions are could we model pathogen movement in air currents and proof of concept of detection of F. oxysporum with spore trapping in key areas in the Caribbean. Xylaria necrophora (Rojas) --  Etiology and epidemiology of taproot decline. Continue work on taproot decline combining remote sensing, disease severity and molecular diagnostics to understand disease progression and epidemiology of the pathogen.  Yield and plant stand were used as parameters, showing an effect of cover crop without pathogen, but the effect increases with pathogen present.  In 2021-2022, we have conducted field trial focused on understanding the epidemiology of Taproot decline caused by X. necrophora.  We have used a combined approach to monitor the disease non-destructively and destructively collecting data using remote and short-distance sensing approaches.  Soil and plant samples were collected for four physiological stages.  We are currently processing samples and using the qPCR developed for quantifying and evaluating the progression of X. necrophora under the three cultivars with high susceptibility to tolerant responses. Milestones for this project include developing an understanding of the biology and epidemiology of X. necrophora for improved disease management practices. There were multiple short-term outcomes achieved, such as development of a qPCR diagnostic tool to evaluate soil and plant samples infested with Xylaria necrophora, conducting a field trial to monitor epidemiology and biology of Xylaria necrophora adapting new technologies such as remote and short-distance sensing to study disease progression. Rhizoctonia solani (Rojas) – Also looking at the population genetics of Rhizoctonia solani AG 1-1A using existing collections at Arkansas but increasing sampling effort in current populations in Arkansas and nearby states. Working on cover crop rotations within a corn-soybean rotation system, data analysis.  Isolates of Rhizoctonia solani have been collected in Arkansas and received from collaborators in the Southern US for genotyping and population genomics analyses. A short term outcome was sequencing of 108 isolates of Rhizoctonia solani AG1-1A from rice (Sheath blight) and soybean (Aerial blight) for genetic diversity analysis. Additionally, we are phenotypically characterizing those isolates for growth rates and tolerance to fungicide.  Milestones for this project include Characterize the genetic diversity of soilborne pathogens, especially Rhizoctonia solani AG1-1A, and the implications on selection of plant resistant material. Implement non-destructive technologies to monitor the effect of soilborne diseases on hosts physiology and performance. We will continue in lab assays and field trials to monitor the efficacy of chemical products to control soilborne plant pathogens. Phytobacteriology and agricultural microbiomes lab (Benitez) – Obj. 1 – Soil management history, fungal communities and SCN infestation.  Soil samples from SCN coalition were stored for microbiome analysis and SCN data.  Using full length ITS region using a third-party lab.  The idea is to fully classify the fungal species present in the soil.  There is no significant difference in diversity across SCN pressure levels.  There are key species already identified that could be associated with healthy areas, such as Trichoderma and Clonostachys.  Also using grid sampling to understand field scale variation in collaboration with Horacio Lopez-Nicora. Phytobacteriology and agricultural microbiomes lab (Benitez) Obj. 2 – cover crop rotation and soybean interaction.  Different rotation systems including corn-soy rotation, corn-rye-soybean, corn-fallow-soybean-wheat-corn.  Most of the analysis is focused corn-rye-soybean rotation to develop an understanding of beneficial nematodes, carbon pools, and the interactions.  Generated were two years of fungal and bacterial diversity data for a corn-soybean and cover crop rotation system, a total of 160 samples were processed for amplicon data. Applied disease management (Spurlock) – On corn, a new product brought to market by FMC was evaluated in on-farm trials as well as traditional replicated small plot research on experiment stations in 2021 and 2022.  The product was determined to cause phytotoxicity in fields where corn was planted relatively early by AR standards.  Efficacy against both soilborne and foliar diseases were inconclusive in 2022 as well.  Due to the phytotoxicity issue, the label was re-written and growers were advised to discontinue placing the product in the seed furrow but rather at least 0.5 inches away from the seed in a 2x2 application. Impacts and upcoming activities within the S1083 group include: Research impacts include the adoption of cover practices by growers in Arkansas, development of diagnostic tools to monitor multiple different soilborne pathogens, adoption of molecular assays by plant health clinics, and revision of chemical fungicide labels due to phytotoxic effects discovered.  New collaborations also resulted, including one with scientists in the Department of Horticulture at the University of Arkansas in order to monitor soilborne pathogens and evaluating the effects on management practices on the soil microbial diversity. The Soil Microbiology and Root Diseases (SMRD) and Diagnostics Committees have joined forces to propose a new activity for the American Phytopathological Society (APS) Councilor's Challenge for 2023, "Developing & Delivering Diagnostics Online Resources (D³OR)." There is an urgent need to create and disseminate new plant pathogen diagnostics tools, especially for soilborne pathogens, that are accurate, up-to-date, and accessible for a wide audience. We proposed to develop and deliver new diagnostic online resources that will open the door for current members to engage in this topic as well as attract new, diverse members to consider careers in plant diagnostics.  There are two major outputs of this program. (1) We will develop digital diagnostics online tools that are short videos created by practicing diagnosticians who work across a spectrum of organizations and who are in different career stages. (2) By leveraging the new call from the APS journal Plant Health Progress, we will write and publish new Diagnostic Guides with a focus on soilborne diseases

Publications

Publications: <ol> <li>Crandall, S.G., Spychalla, J., Crouch, U., Acevedo, F., Naegele, R., Miles, T.D. 2022. Rotting grapes don’t improve with age: cluster rot disease complexes, management, and future prospects. Feature Article, Plant Disease. <a href="https://nam10.safelinks.protection.outlook.com/?url=https%3A%2F%2Fdoi.org%2F10.1094%2FPDIS-04-21-0695-FE&data=05%7C01%7C%7C60b343e00edd492d101b08dad16ec9d0%7C17f1a87e2a254eaab9df9d439034b080%7C0%7C0%7C638052571094226685%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=VPaAdPEUbHbK%2FvurZw3rDeo8R8NluAacCt2MCuOTTko%3D&reserved=0">https://doi.org/10.1094/PDIS-04-21-0695-FE</a>.</li> <li>Gambhir, N., Kodati, S., Huff, M., Silva, F., Ajayi-Oyetunde, O., Staton, M., Bradley, C., Adesemoye, A.O. and Everhart, S.E., 2021. Prevention and detection of fungicide resistance development in Rhizoctonia zeae from soybean and corn in Nebraska. Plant Health Progress, pp.PHP-11.</li> <li>Gambhir, N., Kodati, S., Huff, M., Silva, F., Ajayi-Oyetunde, O., Staton, M., Bradley, C., Adesemoye, A.O. and Everhart, S.E., 2021. Prevention and detection of fungicide resistance development in Rhizoctonia zeae from soybean and corn in Nebraska. Plant Health Progress, pp.PHP-11.</li> <li>Gil, J., Ortega, L., Rojas, J.A. and Rojas, C.M., 2022. Genome Sequence Resource of Burkholderia glumae PhytoFrontiers™, 2(2), pp.140-142.</li> <li>Kodati, S., Adesemoye, A.O., Yuen, G.Y., Volesky, J.D. and Everhart, S.E., 2021. Origin of agricultural plant pathogens: Diversity and pathogenicity of Rhizoctonia fungi associated with native prairie grasses in the Sandhills of Nebraska. PLoS ONE, 16(4), p.e0249335.</li> <li>Kodati, S., N. Gambhir, G. Yuen, A.O. Adesemoye, S.E. Everhart. 2022. Diversity and aggressiveness of Rhizoctonia spp. From Nebraska on soybean and cross-pathogenicity to corn and wheat. Plant Disease. 106:2689-2700.</li> <li>Larson, E.R. and Crandall, S.G. (In-Review). Recovery of the soil fungal microbiome using steam disinfection and biocontrol to manage the plant pathogen Fusarium solani.Special Issue: “Detection, characterization, and management of plant pathogens.” Frontiers in Plant Science. </li> <li>Lin, F., Chhapekar, S.S., Vieira, C.C., Da Silva, M.P., Rojas, A., Lee, D., Liu, N., Pardo, E.M., Lee, Y.C., Dong, Z. and Pinheiro, J.B., 2022. Breeding for disease resistance in soybean: a global perspective. Theoretical and Applied Genetics, pp.1-100.</li> <li>Matczyszyn, J.N., Harris, T., Powers, K., Everhart, S.E. and Powers, T.O., 2022. Ecological and morphological differentiation among COI haplotype groups in the plant parasitic nematode species. Journal of Nematology, 54(1), pp.1-24.</li> <li>Spurlock, T. N. (2022). Evaluation of In-furrow Fungicides on Corn, 2021. Arkansas Corn and Grain Sorghum Research Studies, 2021.</li> <li>Spurlock, T. N., Tolbert, A.C., Hoyle, R.C. (2022). Evaluation of cotton seed treatments against Rhizoctonia solani AG-4 in southeast AR, 2021. (ST009 ed., vol. 16).</li> <li>Spurlock, T. N., Tolbert, A.C., Hoyle, R.C. (2022). Evaluation of cotton seed treatments against Rhizoctonia solani AG-4 on DP1646 B2XF and DP2141B3XF in southeast AR, 2021. (CF119 ed., vol. 16) https://www.plantmanagementnetwork.org/pub/trial/pdmr/reports/2022/CF119.pdf</li> <li>Spurlock, T. N., Tolbert, A.C., Hoyle, R.C. (2022). Evaluation of experimental cotton seed treatments against Pythium ultimum in southeast AR, 2020. (ST008 ed., vol. 16). https://www.plantmanagementnetwork.org/pub/trial/pdmr/reports/2022/ST008.pdf</li> <li>Spurlock, T. N., Tolbert, A.C., Hoyle, R.C. (2022). Impact of biological in-furrow applications on corn in Southeast AR, 2021. (CF097 ed., vol. 16). <a href="https://www.plantmanagementnetwork.org/pub/trial/pdmr/reports/2022/CF097.pdf">https://www.plantmanagementnetwork.org/pub/trial/pdmr/reports/2022/CF097.pdf</a> <a href="https://doi.org/10.1094/PDMR16">https://doi.org/10.1094/PDMR16</a></li> <li>Spurlock, T. N., Tolbert, A.C., Hoyle, R.C. (2022). Impact of foliar and in-furrow fungicide applications on soybean in Southeast AR, 2021. (CF121 ed., vol. 16). <a href="https://www.plantmanagementnetwork.org/pub/trial/pdmr/reports/2022/CF121.pdf">https://www.plantmanagementnetwork.org/pub/trial/pdmr/reports/2022/CF121.pdf</a> <a href="https://doi.org/10.1094/PDMR16">https://doi.org/10.1094/PDMR16</a></li> <li>Spurlock, T. N., Tolbert, A.C., Hoyle, R.C. (2022). Impact of in-furrow fungicide applications on corn in Southeast AR, 2021. (CF098 ed., vol. 16). <a href="https://www.plantmanagementnetwork.org/pub/trial/pdmr/reports/2022/CF098.pdf">https://www.plantmanagementnetwork.org/pub/trial/pdmr/reports/2022/CF098.pdf</a> <a href="https://doi.org/10.1094/PDMR16">https://doi.org/10.1094/PDMR16</a></li> <li>Spurlock, T. N., Tolbert, A.C., Hoyle, R.C. (2022). Impacts of products applied in-furrow on corn in Southeast AR, 2021. (CF099 ed., vol. 16). <a href="https://www.plantmanagementnetwork.org/pub/trial/pdmr/reports/2022/CF099.pdf">https://www.plantmanagementnetwork.org/pub/trial/pdmr/reports/2022/CF099.pdf</a> <a href="https://doi.org/10.1094/PDMR16">https://doi.org/10.1094/PDMR16</a></li> </ol>