Evaluation of resistance of selected bread wheat genotypes of cereal research department of Seed and plant institutes to Fusarium head blight in field conditions

In this study, 224 wheat genotypes which had good agronomic characteristics were selected between 1700 collection of Cereal Research Department, Seed and Plant Improvement Institute, to evaluating against diseases FHB, leaf rust and powdery mildew resistance in field condition in Golestan province. After land preparation, seed of each genotype were planted on a line with length 1.5 meters below mist irrigation systems. Spikes at 50% flowering (stage 65 of the Zadoks) were inoculated with spore suspension of fungi isolates of Fusarium head blight (Fusarium graminearum, F. culmorum) within three days of one another in two stages. To evaluate genotypes resistant to leaf rust, in stem elongation (stage 35 of the Zadoks), were sprayed with a mixture of spores of the pathogen. Genotypes were evaluated to powdery mildew with naturally infected area. Notes the reaction of genotypes diseases mentioned above, the standard method of assessment for all diseases. The results showed that, 60 percent of genotype in disease incidence of Fusarium head blight were moderately susceptible and 30% were susceptible reaction and the rest were moderately resistant and resistant, but in disease severity FHB, 30% of moderately susceptible reaction, 37% susceptible and the rest were placed in resistant and moderately resistant groups. In the disease index FHB of genotypes showed that 20 percent moderately susceptible, 22% susceptible, 34% moderately resistant and 24 percent showed good relative strength. Results evaluated genotypes reaction to leaf rust races in the region showed that 43% resistant, 47% susceptible and others 10 percent were moderately resistant or moderately susceptible. In this study, 17% of genotypes were resistant, 25% moderately resistant, 27% moderately susceptible and 31% were quite susceptible. After analysis of the data, 20 genotypes were favorable partial resistance to any of the diseases studied, were introduced as sources of resistance and molecular genetics of resistance to genetic unit Cereal Research Department, Seed and Plant Improvement Institute.