Genotype x environment interaction and stability analysis in kharif onion

Phenotypic stability for bulb yield and its components were studied in kharif onion over 5 years involving 12 varieties. Wide variation was observed among genotypes, environments (years) and genotype x environmental interaction for all the traits. Both linear and non-linear components of genotype-environment interaction were significant for plant height, bulb weight and yield, where as the non-linear components alone was significant for neck thickness. Three varieties (N-2-4-1. Pusa Madhavi and Pusa Ratnar) were found stable for bulb yield of which only Pusa Madhavi was detected for general adaptability mainly because of better relative growth rate. Other varieties producing higher yield were marked unstable, which included the recommended kharif varieties such as N 53. Agrifound Dark Red and Arka Kalyan. The association analysis revealed that selection for high performance would simultaneously increase responsiveness and instability for bulb yield. The stable variety Pusa Madhavi, which possessed medium bulb, average yield and better keeping quality, was proposed for commercial cultivation in kharif season tinder Bhawanipatna region of Orissa.