Evaluating adult plant resistance of some wheat genotypes to 6E158A+pathotype causing wheat yellow rust

In this study, the reaction of 55 bread wheat genotypes to the dominant race of yellow rust was investigated under field condition in Kermanshah province. The genotypes were selected from four different climates including southern hot and dry, moderate, cold and hot and wet. Adult plant reaction of genotypes to yellow rust was evaluated following artificial inoculation by pathogen in booting stage and flowering stages. Disease severity, area under disease progress curve (AUDPC) and relative area under disease progress curve (rAUDPC) were also measured in wheat genotypes. Then, infection coefficients were calculated by combination of disease severity and infection type. Due to high significant correlation among infection coefficients and AUDPC, the cluster analysis of data was performed based on AUDPC. The wheat genotypes were partitioned to different groups according to 6E158A resistance. The results showed that 25% genotypes had the lowest AUDPC, 18% average level, 14% the highest level and 43% average or high level of AUDPC.