Genotypic evaluation and stability analysis of chilli (Capsicum species) for yield and capsaicin content using AMMI and GGE biplot

Chilli (Capsicum species) is a widely cultivated crop valued for its economic and nutritional significance. However, (G x E) genotype-by-environment interactions often cause variability in yield and biochemical characters, necessitating stability analysis to identify genotypes with consistent performance. The study evaluates 6 chilli genotypes (5 breeding lines and 1 check variety, PLR-1) for yield and capsaicin content across 3 environments in Tamil Nadu: Paiyur, Udumalpet and Yethapur. The study was conducted during the 2023-24, using a randomized block design (RBD) with 4 replications. Agronomic traits including fruit yield per plot and capsaicin content, were recorded. Statistical models, viz. Additive Main Effects and Multiplicative Interaction (AMMI) and Genotype + Genotype x Environment (GGE) biplot, were employed to assess G × E interactions and determine genotype stability. Analysis of variance (ANOVA) revealed significant G x E interactions for both traits, reinforcing the need for stability assessment. PC1 contributes 98 % and 65.5 %, PC2 contributes 2 % and 34.5 % for the 2 characters for the trait yield and capsaicin respectively. G1 (CC-CBE-003) exhibited superior yield (22.87 kg) and high capsaicin content (120451.00 SHU) with stability across locations, making it suitable for fresh and industry purposes. Yethapur (E3) emerged as the most discriminative environment for genotype testing. These findings aid breeding programs in improving productivity and adaptability in chilli.