Genotype × environment interaction and phenotypic stability analysis in niger (Guizotia abyssinica (L.f.) Cass) breeding lines using Eberhart-Russell and AMMI models

Niger (Guizotia abyssinica (L.f.) Cass), an important oilseed crop primarily grown in marginal regions of India, faces significant challenges in production due to environmental fluctuations and a limited genetic base. This study analysed 42 niger genotypes, including two checks, across three sowing settings using the Eberhart-Russell and AMMI (additive main effects and multiplicative interaction) models to measure genotype × environment interaction (GEI) and phenotypic stability. The field experiments were conducted in a randomized block design during the 2021 and 2022 kharif seasons at the zonal agricultural research station, Jawaharlal Nehru Krishi Vishwavidyalaya, Chhindwara, Madhya Pradesh. The analysis of variance demonstrated remarkably significant differences across genotypes, environments and GEI for important agronomic and quality factors. The Eberhart-Russell model revealed genotypes such as JCN-1 and JCN-27 as highly stable and extensively adaptable, based on the regression coefficient (bi = 1) and minimal deviation from regression (σ²di). Genotypes including JCN -3 and JCN-11 revealed great responsiveness to favorable situations, whereas JCN-9 and JCN-20 showed specific adaptability to stressprone environments. AMMI1 biplot indicated high-yielding genotypes like JCN-1 and JCN-16, whereas AMMI2 identified JCN-15, JCN-30 and JCN-31 as widely adapted and stable. Genotypes JCN-20 and JCN-28 were particularly adapted to favorable surroundings, whereas JCN-3 and JCN-21 suited marginal environments. The merging of both stability models proved useful in finding genotypes with extensive and specific adaptation. These results give useful insights for breeders attempting to increase yield stability and adaptation in niger under varied agro-ecological situations.