Delineation of genotype x environment interaction for identification of stable genotypes for different physiological traits in wheat

Heat and drought stress are the major environmental constraints to wheat instability. Climate change enhances Genotype × Environment interactions and urges breeders to step up their efforts to breed cultivars that combine high performance and stability. The current study aimed to assess stability of 100 wheat genotypes grown under eight environments in terms of physiological characters as normalized difference vegetation index (NDVI) and chlorophyll fluorescence. These physiological traits serves as a useful tool for high throughput screening under drought and heat stress for selecting stable wheat genotypes. The pooled analysis of variance due to genotypes, environments as well as genotype × environment interactions were highly significant for these physiological traits according to AMMI biplot analysis indicating the substantial differences in genotypic response across the environments. AMMI biplot study indicated that genotypes WH 1192, PBW 661, PBW 726, HD 2967, PBW 729 and PBW 721 were found stable for NDVI whereas for chlorophyll fluorescence genotypes, WH 1136, WH 1061, WH 1139, WH 1235, PBW 502, WH 1192 were stable across the environments. Therefore, selection for stable genotypes for physiological traits can be used as breeding materials in future wheat programmes as improving physiological responses are being considered to accelerate yield and rate of breeding progress.