MULTI-ENVIRONMENT EVALUATION OF BREAD WHEAT GENOTYPES FOR YIELD STABILITY USING AMMI APPROACH

Abstract

Bread wheat is a vital staple crop worldwide, but its production is prone to various environmental constraints and yield reduction associated with adaptation. To identify stable and adaptable genotypes, a total of 30 wheat genotypes were evaluated for their genotype-environment interaction (GEI) and stability across three different seasons as season, late and very late sowing for two years using Additive Main Effect and Multiplicative Interaction (AMMI) and Eberhart and Russell Stability model. According to analysis of variance, all traits were significantly except spikelet per spike (SPS), indicating differential genotypic responses across environments. Using the Eberhart and Russell stability model, the highest number of stable genotypes was recorded for grain yield, while plant height and grain yield showed the greatest proportion of genotypes classified as adaptable. Overall, among all 30 genotypes including HD 2932, HD 3118, HD 3086, PBW 644, LOK1, PBW 804, DBW 46, and DBW 51 emerged as the most stable performers for grain yield, demonstrating consistent expression across environments.  From, AMMI1 biplots showed that environment 2 displayed the lengthiest vector, indicating the sturdiest interaction, while environment 1 and environment 3 exhibited minimal interaction. Genotypes such as PBW 644, LOK 1, PBW 804, DBW173, and GK 307 had near-zero IPCA1 scores, marking them as highly stable, although only DBW 150, DBW 173, and HD 3118 achieved above-average yields. Conversely, PBW 723, HD3043, GW 366, and DBW14 were the most unstable based on their large IPCA scores. High-yielding genotypes with negative IPCA1 values—including HD3118, DBW 46, and HI 1563 demonstrated desirable performance. The AMMI2 biplot, which isolates G×E interaction, confirmed that genotypes near the origin (PBW 644, LOK 1, DBW 107, HD3118, DBW 46) were least influenced by environmental variability. Overall, DBW 107 and PBW 644 emerged as the most stable, high-yielding genotypes across environments.