Location: Sunflower Research
Project Number: 3060-21220-028-25
Start Date: Jun 01, 2014
End Date: Sep 30, 2015
Screening procedures will be optimized to verify two forms of partial resistance to S. sclerotiorum in pea, lesion expansion inhibition (LEI) and nodal transmission inhibition (NTI), using a detached stem screening method. One set of 5 internodes of equal length and weight of a single PI line and another set of 5 internodes with node of same line will be tested with S. sclerotiorum to quantify the time required for S. sclerotiorum to pass through the node and isolate the nodal transmission inhibition resistance phenotype for all 90 PI lines. The optimized screening procedures will be applied to two mapping populations to further investigate and validate QTL for LEI and NTI in recombinant inbred lines (RILs) derived from the crosses Lifter/PI240515 and PI169603/Medora. Candidate SSR markers will be designed using sequence data obtained from partially resistant line PI240515 and susceptible line Lifter after infection with S. sclerotiorum, and run on mapping populations to identify closely linked markers to QTL associated with partial resistance.