Project Number: 5442-21220-028-07
Project Type: Specific Cooperative Agreement

Start Date: Jul 01, 2012
End Date: Sep 30, 2013

Objective:
1) Identify resistance to white mold in wide cross and adapted dry and snap bean lines; and 2) Assess the phenotypic and genotypic variation in common bean isolates of Sclerotinia sclerotiorum from major bean production areas.

Approach:
Multiple field location and greenhouse screening tests will be used to determine white mold reaction of putative sources of resistance. These lines will be provided by bean breeders and pathologists from recombinant inbred line populations, interspecific hybridizations, and breeding lines. Field plots will be located in areas of Oregon, Michigan, Wisconsin, North Dakota, Nebraska, and Washington with a history of white mold. All field locations plus Idaho, Colorado and New York will conduct greenhouse tests. Variations in dry and snap bean isolates of S. sclerotiorum will be assessed by determining mycelial compatibility groups of isolates from bean growing areas in the U.S., and comparing them with compatibility groups from white mold screening nurseries in the same area, e.g. Red River Valley, ND. The aggressiveness of the above S. scleroriorum isolates will be determined by the straw test. The intraspecific variation in S. scleroriorum greenhouse isolates and field isolates collected at each screening trial site and bean growing areas will be determined by the use of 16 microsatellite-specific primers. Isolate by location interaction will be studied in inoculated fields. Pathogen variation knowledge will guide use of specific screening isolates for breeders and plant pathologists.