Developing a Comprehensive Management Program for Foliar Diseases of Soybean (Year 1 of 2262)
Sustainable Production
(none assigned)
Parent Project:
This is the first year of this project.
Lead Principal Investigator:
Ahmad Fakhoury, Southern Illinois University
Co-Principal Investigators:
X B Yang, Iowa State University
Boyd Padgett, Louisiana State University
Burton Bluhm, University of Arkansas
John Rupe, University of Arkansas
Carl Bradley, University of Kentucky
Grover Shannon, University of Missouri
Rouf Mian, USDA/ARS-Ohio State University
Alemu Mengistu, USDA/ARS-West Tennessee Experiment Station
Melvin Newman, USDA-ARS-Jackson, TN
+8 More
Project Code:
Contributing Organization (Checkoff):
Institution Funded:
Brief Project Summary:

Unique Keywords:
#foliar diseases, cercospora leaf blight, frogeye leaf spot, soybean vein necrosis virus, #foliar fungicides, phomopsis seed decay, septoria brown spot, #fungicide resistance, #soybean diseases
Information And Results
Project Deliverables

Commercial varieties and public germplasm will be identified with resistance to frogeye leaf spot. Variety results will allow producers, seed companies, consultants, etc. to select resistant varieties. If producers have access to resistant varieties, this will presumably reduce the need for applying fungicides. It will also provide a needed resource to producers with fungicide resistant isolates.

Public lines that are identified with resistance will assist plant breeders with developing new varieties. Potentially new resistance genes from Plant introductions will position breeding programs to have these genes in germplasm, should races develop that can defeat Rcs3.

A forecast system: A soybean foliage disease forecasting system will be developed that provides a weekly disease outlook in advance in the U.S. soybean production regions. Thus climate-disease coupled model system integrates several modular components of short- to mid-term weather/climate prediction, turbulent diffusion and windborne transport, and soybean disease development.

Forecast products: At the end of project, the system will be able to provide weekly disease outlooks showing disease severity and spread over major soybean production regions, initially focusing on a few states and eventually the entire Southern and North Central Regions of the U.S.

Final Project Results

This project (started Oct. 2011) is combining efforts of 12 researchers in 7 states to establish management and control strategies for soybean foliar diseases, mainly frogeye leaf spot (Cercospora sojina) but also brown spot (Septoria glycines), Cercospora leaf blight (Cercospora kikuchii), and phomopsis (Phomopsis longicolla). Progress has been made in each of the 7 objectives:
• At the Univ. of Arkansas, a greenhouse experiment was set up to characterize the cellular basis of C. sojina resistance by comparing lines with defined resistant genes (Rcs1, Rcs2, Rcs3).
• At the Univ. of Illinois, C. sojina samples are being collected from rust sentinel plots to be tested as mutants that may be resistant to strobilurin fungicides to better understand the distribution of fungicide resistance.
• Melvin Newman of the Univ. of Tennessee is setting up two field locations to study strobilurin and triazole fungicide resistance.
• The Univ. of Missouri and Ohio State Univ. have initiated breeding programs to develop C. sojina resistant varieties. Missouri reports the development of 4 lines, including two RR lines, with the Rcs3 gene and good agronomics. As well, Alemu Mengistu of USDA at Jackson TN will test resistant lines in a field screening nursery.
• The Universities of Arkansas and Louisiana State are setting up for field trials to test fungicide control of Phomopsis seed decay.
• XB Yang of Iowa State Univ. is developing plans to study the epidemiology of brown spot, frogeye leaf spot, and Cecosporsa leaf blight in order to create a disease forecast program.
• Additionally, the Univ. of Arkansas has been collecting 55 Cercospora kikuchii isolates to identify virulent strains and ability to produce the toxin cercosporin for use in screening assays.

Progress has been made to develop novel sources of resistance to Frogeye Leaf Spot. For the first time, resistance sources to Cercospora Leaf Blight have been initially identifed. New means to screen for these two major diseases are under development to enhance the breeding for resistance. Methods to detect fungicide resistance of Frogeye strains to foliar fungicides has been determined, that in turn, has led to establishment of a geographic map for incidence of fungicide resistance. Foliar fungicides are screened annually for efficacy against all major foliar diseases and published widely. A prediction system for Septoria brown spot has initially been developed.

The United Soybean Research Retention policy will display final reports with the project once completed but working files will be purged after three years. And financial information after seven years. All pertinent information is in the final report or if you want more information, please contact the project lead at your state soybean organization or principal investigator listed on the project.