Screening of China Aster [Callistephus chinensis (L.)] Genotypes and F1 Hybrids against Alternaria Leaf Spot Disease

Leaf spot disease caused by Alternaria alternata (Fr.) Keissler is a threat of China aster cultivation and is capable of causing yield losses in all production regions. The experiment was undertaken to screen genotypes and F1 hybrids which would be helpful in developing Alternaria leaf spot resistance varieties in later years. AAC-1 was found to be resistant against Alternaria leaf spot in both field and control conditions. In natural disease pressure, Arka Kamini, Arka Shashank and Arka Poornima recorded to be moderately susceptible, susceptible and highly susceptible to Alternaria leaf spot, respectively. However, in artificially inoculated condition, Arka Kamini showed susceptible reaction. Among F1 hybrids, AAC-1 x Arka Kamini and Arka Kamini x AAC-1 showed moderately resistant reaction; AAC-1 x Arka Poornima, AAC-1 x Arka Shashank, Arka Poornima x AAC-1, Arka Shashank x AAC-1 showed moderately susceptible disease reaction for Alternaria leaf spot.