Genetic Analysis for Partial Resistance to an Iranian Strain of Bacterial Leaf Streak (X. campestris pv. hordei) in Barley

Seven barley genotypes with high genetic variability for resistance to bacterial leaf streak (Xanthomonas campestris pv. hordei) were crossed in diallel fashion to determine the inheritance of resistance to this disease. Two experiments were undertaken in a controlled growth chamber using a complete-block design with four replicates. Each replicate consisted of a row of 20 seedlings per parent or F₁ hybrid. An Iranian strain of bacterial leaf streak was used for inoculation of 12-day-old seedlings. Results showed that the cultivars ‘Express’ and ‘Morex’ and the Iranian pure line Iran-3a had a high partial resistance in booth experiments. Diallel analysis showed highly significant general and specific combining abilities. ‘Morex’ and Iran-3a were the best combiners for partial resistance to bacterial leaf streak in barley and could be successfully used for breeding purposes.