Investigation of Barley (Hordeum vulgare L.) Advanced Lines for Resistance to Powdery Mildew Disease under Field and Greenhouse Conditions

Barley (Hordeum vulgare L.) is one of the widely cultivated cereals and several pathogenic factors affect its grain yield quantity and quality. The fungal pathogen Blumeria graminis f. sp. hordei (Bgh) causes powdery mildew, which is a common leaf disease, and identifying genotypes resistant to this disease is one of the goals of breeding programs to combat this disease. The present study was conducted to investigate the resistance of 104 barley genotypes (including 99 advanced lines of barley along with five control cultivars) to powdery mildew disease under field (in two planting dates) and greenhouse conditions. The assessed traits included the severity of the disease, the infection type, and the area under the disease progression curve (AUDPC). The results of analysis of variance of the data showed that the effect of genotype on all the evaluated traits was significant (P<0.01). Considering the evaluation of genotypes under the field on two planting dates for the severity of the disease, and the results of cluster analysis of genotypes based on the different traits investigated in the greenhouse, totally 15 and 19 genotypes were identified as the most resistant and sensitive genotypes to this disease, respectively. These identified genotypes can be used for introducing to the disease-prone regions and also exploited in the formation of breeding populations and as important sources of candidate resistance genes to this disease.