Progress report for LNC20-443
The project titled “Identifying and Expanding Integrated Disease Management Resources to include Organic Grains in Support of Organic and Transitional North Central Farms” aims to increase the success of organic grain farms in the North Central Region. The demand for domestically-produced organic grain continues to increase, offering the opportunity for farmers in North Central Region to diversify their crop rotations and increase opportunities for the integration of cover crops. However, high disease incidence affects both quality and yield of organic grain, significantly limiting the expansion of acres. While organic farmers use a combination of strategies, including crop variety selection and crop rotation, to minimize disease occurrence, a dearth of information exists as to the efficacy of low-risk and organic-approved inputs to augment an integrated, ecological approach to disease management. Additionally, while cover crops managed as green or killed mulches are increasingly used as an ecological weed management tool (1), regionally-specific research is lacking regarding the impact of these cropping systems approaches on disease occurrence and management. This proposal aims to develop integrated disease management tools, providing farmers with rigorous, replicated data to optimally combine genetic, agronomic, and input-based tools into an Integrated Disease Management plan. An evaluation network will be developed to provide unbiased, replicated university data on OMRI approved products and cultural practices for organic grain crops. This project will initially focus research on three critical diseases in North Central grain production, Fusarium head blight on wheat (caused by Fusarium graminearum), white mold on soybean (caused by Sclerotinia sclerotiorum), and tar spot of corn (caused by Phyllachora maydis). Research results will contribute to the development of integrated disease management extension and outreach material aimed towards organic farmers working in Midwest grain cropping systems.
Our overall objective is to expand Integrated Disease Management (IDM) tools to include options for North Central organic grain production.
Objective 1. Organic IDM field trials with a focus on Fusarium head blight of wheat, white mold of soybean, and tar spot of corn.
Objective 2. Develop Organic-Based IDM outreach materials for North Central farmers.
This proposal initiates research required to fill this gap and establish testing and communication networks similar to those currently used in conventional production. Additional outcomes include increased use of lower-risk pesticides, and increased success and sustainability of farms transitioning or currently implementing certified organic production.
This project is unique as it aims to expand the limited tools and guidelines for disease management in organic grain production. The initial focus will be on three yield-limiting diseases of corn, soybean, and wheat production in the North Central Region. It will allow the establishment of integrated disease management trials for organic grain production in these crops as a pipeline for university based unbiased research.
Fusarium head blight, caused by Fusarium graminearum, and subsequent mycotoxin (deoxynivalenol (DON)) can cause annual losses in wheat (2). Fusarium head blight levels vary each year based on weather conditions, but it is constantly present and of concern to growers in the North Central Region. In 2018, 1.63% loss in wheat production were reported in the North Central States a value of $91.7 million (17.81 million bu loss) (3). In 2019, high levels of Fusarium head blight and subsequent DON production caused multiple load rejections across Indiana and Wisconsin. Current recommendations are limited for organic disease management in wheat.
White mold, caused by Sclerotinia sclerotiorum, contributed to 57,089,000 bu loss in the northernmost United States in 2017 (3;4), and in 2018 an estimated 1.1 million bu loss occurred in Indiana and 2.4 million bu loss in soybean in Wisconsin (3). Recent research in the northeast indicate that rye cover crops and biological control strategies can reduce white mold in dry bean and soybean production systems (5; 6); however, little is known regarding their utility and implementation in organic production systems in the North Central Region.
Tar spot of corn has spread from initial detection in 2015 and has become established in nine states (Florida, Illinois, Indiana, Iowa, Michigan, Minnesota Missouri, Ohio, and Wisconsin). In 2018, tar spot caused 20-60 bu/A yield losses in corn production areas of upper Indiana and most of the corn belt of Wisconsin (7). Yield losses totaled more than $658 million in the North Central Region (3). Management options for tar spot is currently limited in both conventional and organic corn production. Complete hybrid resistance is not known and fungicide efficacy is limited and depends heavily on timing. In organic productions systems, nothing is known about efficacy of OMRI approved products for use against tar spot.
A search of resources currently available for disease management in organic grain production is limited nationally and none are readily available for the North Central Region. Most information that is provided from disease management in organic grains is general in nature without specific efficacy information about OMRI approved products. In addition, there are currently 366 active ingredients registered as biopesticides (biochemical and microbial) under the EPA and over 1500 products listed for crop pest, weed, and disease control in a OMRI product search (8,9). Plant Disease Management Reports are a way for rapid sharing of plant disease management results – a search of those led to only 247 records with organic product evaluation and only 20 were on field crops (3 on organic barley, and 17 organic rice) (10). These demonstrate that there is still a large gap in providing unbiased efficacy data to be used by organic grain farmers to help them make disease management decisions on their farms. This proposal aims to initiate research to begin to fill this gap. Especially as many of our farms are looking at new ways to generate on-farm revenue, specializing in organic grain production may be a venue, developing resources for them to successfully transition is of great need.
Field crop diseases affect both quality and yield of organic grain, potentially limiting the expansion of acres. This proposal aims to develop integrated disease management tools, providing farmers with rigorous, replicated data to optimally combine genetic, agronomic, and input-based tools into an Integrated Disease Management plan. Expansion of these tools will increase the financial success and sustainability of farms transitioning or currently implementing certified organic production.
Our proposal aims to establish an evaluation network that will provide unbiased, replicated university data on OMRI approved products and cultural practices for organic grain crops. This information can be used by all grain crop production systems to augment an integrated, ecological approach to disease management, increase the use of cover crops, and identify lower-risk pesticides that will help to sustain and improve environmental impacts in agriculture.
The multi-faceted approach for organic integrated disease management (IDM) will include the following objectives:
Objective 1. Organic IDM field trials with a focus on Fusarium head blight (FHB) of wheat, white mold of soybean, and tar spot of corn.
Multi-year trials will be established at both Purdue Agricultural Centers and Wisconsin Agricultural Research Stations, and at on-farm demonstration sites based on crop and disease history. All trials will be managed according to standard organic and agronomic practices. Treatment applications will be made according to current weather-based prediction models for each disease. These include using the Fusarium Risk Assessment Tool for Fusarium head blight of wheat (wheatscab.psu.edu), Sporecaster App for white mold on soybean (11), and new Tarspotter App for tar spot of corn (12). A randomized complete block design with four replications will be used as standard trial design. A preliminary list of OMRI products for evaluation include those that contain Coniothrium minitans, Bacillus amyloliquifaciens, Reynoutria sachalinensis, Streptomyces lydicus, and copper hydroxide. Data collection will include standard incidence and severity for each disease, yield parameters, on-site weather data, and cost analysis for feasibility. The organic corn, soybean and wheat enterprise budget tools from Purdue will be leveraged for cost analysis (13). All data will be analyzed using a mixed model analysis of variance (P=0.05) and means separated using least significant difference (LSD; α=0.05).
1a. IDM for FHB in organic winter wheat. Research question: Are there current varieties and OMRI products available that can minimize FHB in organic wheat?
Wheat trials will be established the preceding fall for implementation in the spring. A factorial experimental design of variety and OMRI products will be established. University sites will be inoculated approximately 24-36 hours after the anthesis treatment is applied with a spore suspension (50,000 spores/ml) consisting of a mixture of Fusarium graminearum isolates endemic to each location. Each state will identify at least two modern organic wheat varieties using Scab Smart that show moderate resistance to Fusarium head blight and at least four OMRI approved products for evaluation, these will be applied Feekes 10.5.1.
Treatment list for OMRI products evaluation in wheat:
- Non-treated control
- Prosaro 421 SC 8.2 fl oz/A – standard conventional product
- ChampION 50 WP 1.5 lb/A
- Regalia 1 qt/A - Reynoutria sachalinensis
- SONATA 1 qt/A – Bacillus pumilus – QST 2808
- Actinovate 12 oz/A - Streptomyces lydicus- WYEC 108
Data collection will include Fusarium head blight standard incidence and severity ratings on 60-100 spikes per plot at the soft dough stage (Feekes 11.2) (14). Additional foliar diseases if noted will be documented and rated for percentage of flag leaf severity. Plots will be harvested with a plot combine and yield and test weight determined. Subsamples of grain from each plot will be tested for Fusarium damaged kernels (FDK), deoxynivalenol (DON) and bread-making quality.
1b. IDM for white mold in organic soybean. Research questions: Can an integrated approach provide adequate white mold control in organic soybean? Trials will be established in fields with a history of white mold and/or infested with S. sclerotiorum. A factorial experimental design of tillage/cover crop, variety, and OMRI products will be used. A rye cover crop will be established the preceding fall for implementation of tillage in the trial in the spring. Tillage treatments will include tilled and no-tilled with rye roller-crimped. Two soybean varieties Dane and MN1410 both with moderate resistance will be planted. Foliar fungicide treatments will be applied based on Sporecaster App during soybean flowering from R1 to R4. The app forecasts the presence of apothecia in a field predicting the optimum timing for white mold treatment.
Treatment list for variety and OMRI product evaluation in soybean:
- Tilled non-treated control.
- No-tilled with rye roller-crimped
- Non-treated control
- Aproach 2.08 SC 8.0 fl oz/A – standard conventional product
- Double Nickel LC 2 qt/A – Bacillus amyloliquifaciens - D747
- Serifel 16 oz/A - Bacillus amyloliquifaciens – MBI600
- Actinovate 12 oz/A - Streptomyces lydicus - WYEC 108
- BotryStop 2 lb/A - Ulocladium oudemansii - U3
Data collection will include assessing Sclerotinia stem rot disease severity index (DSI). Thirty plants arbitrarily selected from the plots will be scored on a scale of 0-3 where 0=no infection; 1=infection on branches; 2=infection on mainstem with little effect on pod fill; 3=infection on mainstem resulting in death or poor pod fill. The scores of the 30 plants will be totaled and divided by 0.9 to generate DSI (12). The two center rows of each plot will be harvested and yields adjusted to 13% moisture.
1c. OMRI product efficacy trials for tar spot of corn. Research question: Do OMRI approved foliar fungicides show efficacy against tar spot of corn?
A simple randomized complete block experimental design will evaluate at least four OMRI products. Initial treatments will occur based on disease scouting, crop growth stage, and Tarspotter, a tar spot disease forecasting app, with application targeted at tassel or flowering and applied once or twice during the growing season. A top selling organic hybrid will be used in each state such as Blue River 38G54 (96 RM) or Great Harvest 52F3GH (102 RM).
Treatment list for OMRI products evaluation in corn:
- Non-treated control
- Headline Amp 14.4 fl oz – standard conventional product
- Serifel Bacillus amyloliquifaciens – MBI600
- Actinovate 12 oz/A - Streptomyces lydicus- WYEC 108
- Badge 1.8 pt/A – copper oxychlride + copper hydroxide
- Oxidate 2.0 – hydrogen peroxide + peroxyacetic acid
Data collection will include a minimum of three disease ratings including 2-week post application and at R5/R6. Disease ratings will include separate measurements of tar spot and other leaf diseases present. A minimum of 5 ear leaves per plots will be scored and averaged. The standardized tar spot rating chart will be used to record two numbers: one for percentage of tar spot stroma (fungal fruiting bodies), and one for symptoms of infection that include chlorosis, necrosis and leaf blight. A plot-wide estimate of percentage green canopy will be taken at the final R5 rating. Lodging scores will be collected where appropriate. The two center rows of each plot will be harvested and yields adjusted to 15.5% moisture.
1d. Assess new products, practices and disease risk on current organic grain farms. Two farms in each state will evaluate one or more of the IDM practices or products listed above on their farm. In addition, four farms in both states will be identified to work closely to scout for disease risk in all three crops (wheat, soybean, and corn). Data collected will include diseases (identification and severity) and production practices. This data will increase understanding of the feasibility of these IDM practices, current disease risks, and direct future research objectives with regards to organic grains disease management.
Objective 2. Develop Organic-Based IDM outreach materials for North Central farmers.
- Develop an Organic Grains Integrated Disease Management (IDM) Toolbox. The Organic Grains IDM Toolbox will be a web-based resource serving as a clearinghouse for information on genetic, agronomic, and input-based IDM tools for organic grains in the North Central Region.
- Development of Organic Grains Product Efficacy Tables for corn, soybean and wheat. These publications will be prepared in coordination with the Crop Protection Network and made available through the Organic Grains IDM Toolbox.
- Organic field days and conferences: Once each summer a field day integrating discussion-based education of organic IDM strategies and highlighting the research implemented will be held in each state. In Indiana, this will be held in conjunction with the Organic Agriculture Summer Program Series and held at the Pinney Purdue Agricultural Center, where both the soybean and corn research trials will be located. An additional field day in the summer program series could feature a cooperating farm that is testing a product or practice as part of the project. In Wisconsin, this program will be held in conjunction with the OGRAIN field days or at the annual organic field day at UW-Arlington. Findings will also be presented at Purdue Extension’s Indiana Organic Grain Farmer Meeting and UW-Madison’s OGRAIN Conference, 2-day conferences that have emerged in recent years as important regional farmer-focused organic grain education and networking events. At all programs, participants will be surveyed at the field days to document new knowledge gained and future implementation of IDM on their farms.
- Willbur, J. F., Fall, M. L., Byrne, A. M., Chapman, S. A., McCaghy, M. M., Mueller, B. D., Schmidt, R., Chivers, M. I., Mueller, D. S., Kabbage, M., and Giesler, J., Conley, S. P., and Smith, D. L. 2018. Validating Sclerontina sclerotiorum apothecial models to predict Sclerotinia stem rot in soybean (Glycine max) fields. Plant Disease. 102:2592-2601. https://doi.org/10.1094/PDIS-02-18-0245-RE.
- Smith, D. 2019. Tar spot on my mind. Crops, WCM Newsletter. June 20, 2019. (https://ipcm.wisc.edu/blog/2019/06/tar-spot-on-my-mind/.
- Crop Economic Resources. Purdue Agriculture Center for Commercial Agriculture. (https://ag.purdue.edu/commercialag/Pages/Resources.aspx?cat=Crop+Economics).
- Stack, R. W., and McMullen, M. P. 1998. A visual Scale to estimate severity of Fusarium head blight in wheat. NDSU Extension Service: Small Grains Publications. Online Publication/PP-1095.
- Grau, C. R., Radke, V. L, and Gillespie, F. L. 1982. Resistance of soybean cultivars to Sclerotinia sclerotiorum. Plant Dis. 66:506-508
The first year of research trials in wheat, soybean and corn were conducted in Indiana and Wisconsin for Objective 1 were completed, and we are currently summarizing the data across locations. Field plans for the 2022 season have begun and we will be making some adjustments to add resistance to the corn trials and varieties in the soybean trials.
In 2021, weather conditions were not favorable for Fusarium head blight (FHB). No differences between treatments for FHB incidence, severity and Index and non-treated control on 11 Jun. The % of Fusarium damaged kernals (FDK) was lowest in the Kaskaskia variety and when treated with Prosaro and Actinovate. The concentration of deoxynivalenol (DON) was lowest in the variety Kaskaskia. An application of Pacesetter increased DON over non-treated. There was no difference in treatment for wheat yield.
In Indiana 2021, very little white mold developed in plots. White mold was not observed in the plots. Frogeye leaf spot was the most prominent disease in the trial, but only reached low severity. Main effects of variety, cover crop termination, and fungicide treatments are presented since no significant interactions between tillage, variety, fungicide, except for tillage by variety in yield. Frogeye leaf spot severity was significantly reduced in the variety Dane when compared to MN1410. Roller-crimped rye increased yield of Dane as compared to full tillage, but there were no differences in yield of MN1410 with cover crop termination treatment.
In 2021, weather conditions were favorable for tar spot and it reached high severity. All fungicide treatments reduced tar spot stroma severity on ear leaf over the non-treated control. Headline Amp significantly reduced the percentage of symptomatic tissues on ear leaf. There was no significant difference between treatments for severity of NCLB on ear leaf. Headline Amp had a highest percent of green plots and corn yield. There were no significant differences between treatments for harvest moisture and test weight.
The suite of outreach tools and training that we plan to develop will provide new Integrated Disease Management (IDM) tools that can effectively target a wide range of clientele from agribusiness personnel to individual farmers and agricultural professionals in each state annually. Our aim is to help them meet the demand for domestically produced organic grain and increase their success and sustainability in transitioning or currently implementing certified organic grain production.
Educational & Outreach Activities
1/5/2021 OGRAIN Virtual Info Exchange, “Reducing Tillage in Organic Grain Systems.” 40 attendees.
1/22/2021 OGRAIN Friday Virtual Workshop, “Variety selection and disease management in organic food-grade grain production.” 50 attendees.
2/15/2021 OGRAIN Friday Virtual Workshop, “Reducing tillage in organic grain productions - latest in agronomics and equipment.” 150 attendees.
2/2/2021 Silva, E.M. 2021. Cover Crop-Based Organic Reduced Tillage Grain Production. Kentucky Organic Association Conference (Virtual Meeting).
2/19/2021 OGRAIN Virtual Info Exchange, “Reducing Tillage in Organic Grain Systems.” 40 attendees.
3/2/2021 OGRAIN Virtual Info Exchange, “Reducing Tillage in Organic Grain Systems.” 40 attendees.
5/26/2021 Badger Crop Connect, “Agronomic management with roller crimped winter cereal rye. 200 attendees.
7/1/2021 Cover crop termination field day at Arlington, “Using a roller-crimper to terminate cereal rye.” 75 attendees.
8/3/2021 NEPAC Organic Field Day, IN, Various presentation on organic ag research. 19 attendees.
8/24/2021 Organic Ag Field Day, WI, Various presentations highlighting organic ag research. 100 attendees.
10/7/2021 Biological Farmer Friends Field Day, Dane Co, WI, “Interseeding and roller-crimping.” 100 attendees.
- Identification of plant diseaese
- Agronomic management with roller crimped winter cereal rye