International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru-502 324, Andhra Pradesh, India. E mail: r.sharma@cgiar.org
Genetic resistance to downy mildew (Sclerospora graminicola) in parental lines of pearl millet (Pennisetum glaucum) is critical for successful commercial cultivation of hybrid cultivars. In this study, 23 genetically diverse B-lines were evaluated against two highly virulent as well as old and new pathotypes of S. graminicola from two agroclimatic zones in India. Significant differences were found among genotypes, pathotypes and their interactions for downy mildew incidence. The downy mildew incidence across test B-lines ranged from 0 to 100% and the reaction of the lines to different pathotypes varied considerably. Eight B-lines (ICMB 01777, -02333, -03888, -03999, 05333, -06555, -06888 and -07666) exhibited high levels of resistance across pathotypes. These resistant lines could be used in the development of F1 hybrids with stable resistance to diverse pathotypes of downy mildew in India.
Resistance, B-lines, Sclerospora graminicola, pathotypes, pearl millet
