Location: Grain Legume Genetics Physiology Research
Project Number: 2090-21220-003-009-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Sep 1, 2026
End Date: Feb 28, 2028
Objective:
The objectives of this cooperative research agreement are to identify pathogens responsible for Bacterial Blight and Ascochyta Blight diseases or winter pea and detect genetic markers associated with disease resistance in pea.
Approach:
Objective 1: Identify pathogens associated with Bacterial Blight and the Ascochyta Blight of winter pea.
Winter pea fields across the pulse growing region of Idaho and Washington will be examined for symptomatic plants. Surveys will be conducted at different periods of time following freeze events or storms that are conducive for disease development. Symptomatic tissues, including leaves, stems, and pods, will be collected using standardized procedures. Standard procedures will be used to isolate bacterial and fungal pathogens from symptomatic tissues. Isolates will be maintained on appropriate medium and stored for future use in greenhouse trials. Pathogen populations will be characterized across environments based on frequency of occurrence, species composition, and geographic distribution. Bacterial and fungal isolates will be characterized using DNA sequence analysis (MLSA) to further understand variation in the pathogen populations.
Objective 2: Evaluate a genetic mapping panel of pea lines to identify sources of resistance to Bacterial Blight and Ascochyta Blight.
A panel of 286 different pea lines will be screened under greenhouse and field conditions. In the greenhouse, plants will be inoculated with bacterial and fungal pathogens collected from Objective 1. Disease responses will be evaluated by recording disease incidence and disease severity based on percentage of infected tissue. Field studies will also be conducted to test for disease resistance. Field trials will consist of single row plots (1.5 m long) with three replicated plots per entry. Plots will be assessed for disease incidence and severity. Selected agronomic traits, including plant height and plant vigor, will also be measured. Because the pea lines are already genotyped, the disease response data will be used for a genome-wide association study (GWAS) to identify DNA markers associated with disease resistance.