Partial resistance components for the management of spot blotch pathogenBipolaris sorokinianaof barley (Hordeum vulgareL.)

Eighty barley genotypes were evaluated for partial resistance components of spot blotch disease of barley caused by Bipolaris sorokiniana under field conditions. Barley genotypes were inoculated with 29 B isolate of Bipolaris sorokiniana and the Area Under Disease Progress Curve (AUDPC), size of lesion, number of lesions leaf−1 and number of spores lesion−1 were recorded for penultimate leaves. A wide range of variation was observed for the components of partial resistance in barley genotypes. AUDPC and size of lesion identified as first principal components for the resistance. Further cluster analysis clustered genotypes into 10 groups and barley genotypes BCU5592, BCU5613, BCU1452, BCU138 and BCU133 exhibited low AUDPC, smaller lesion size, less number of lesions leaf−1 and less number of spores lesion−1. Selecting these genotypes exhibiting resistant components could be helpful in reducing losses caused by disease and thus contribute to increased yield.