Screening of some Barley Lines Against Powdery Mildew Agent and Considering of NH1 and Several Pathogenesis Related Genes in Disease Resistance

Barley is one of the most important cereals in animal nutrition and it has a role as a substitute source of wheat and rice in diet nutrition. This product is always exposed to damaging factors such as pests and diseases which lead to reduce yield and quality. The Powdery mildew agent, as a biotrophic fungus, seriously causes damage in some barley plantation areas. Similar to other plants, barley employs diverse mechanisms against the disease based on proteins and other antimicrobial agents such as pathogenesis- related proteins which have essential roles in disease resistance. In this study, morphological and molecular analyses were conducted on some barley genotypes after challenge inoculation with Blumeria graminis f.sp hordei (Bgh), the causal agent of powdery mildew. For this purpose, 11 barley cultivars were selected for initial screening. Result from data analysis showed that Mb-86-5 was the most susceptible cultivar and in Avt/Attiki, Ceres, BIR, L.1242, Yousef, Nosrat, Mahoor, Comp-1-71E and Rihane-03 cultivars, the rate of Bgh colony number significantly decreased when compared to susceptible Cv. The susceptibility rate between Beecher and Mb-86-5 was not significant. Determination of the genes expression involving in disease resistance, carried out on one- week old seedling. For all samples total RNAs were extracted. Molecular investigation showed that PR1, PR5, NH1, POX genes enhanced significantly in resistant cultivar Ceres when compared to Mb-86-5 susceptible genotype. Results of this study indicate that the mentioned genes are involved in powdery mildew disease resistance in Ceres barley genotype.