investigation of resistance to chocolate spot (botrytis fabae sard) in faba bean (vicia faba l.) in gorgan region

fungal diseases, chocolate spot (botrytis fabae sard) is the most destructive diseases of faba bean and causes considerable dramatic damage losses on faba bean yield worldwide. the levels of resistance to chocolate spot were evaluated in 35 faba bean cultivars and one susceptible check (ilb365) and local check (barkat) at the gorgan agricultural research station during the 2010 and 2011 cropping seasons. the obtained results showed a significant difference (p< 0.01) among genotypes for yield, yield component and related traits to disease resistance. barkat, flip03-35fb and flip03-58fb produced the highest plant height, seed yield and 100 seed weight, respectively. in order to determine genotype reaction to chocolate spot, disease symptoms scored in certain intervals until harvest, then audpc, raudpc and saudpc was calculated. a significant variation among the tested genotypes and their reaction to chocolate spot disease was found. results of variance, comparing the mean and also cluster analysis revealed that ilb 365, flip03-57fb, flip03-43fb and flip03-59fb where susceptible. whereas, icarus, flip03-29fb, flip03-30fb, flip03-34fb and flip03-52fb introduced as resistance genotypes to chocolate spot judged by the lowest audpc.