Stability Analysis of Yield and Yield Attributing Traits in Grasspea (Lathyrus sativus L.) Across Sowing Environments

Abstract

Background: Grasspea (Lathyrus sativus L.) is a climate-resilient pulse crop valued for its adaptability to marginal environments and rice-fallow ecosystems. However, genotype × environment (G × E) interaction often limits the identification of high-yielding and broadly adapted genotypes. Aim: This study aimed to evaluate the stability and adaptability of grasspea genotypes for seed yield across different sowing environments and to identify stable, high-performing genotypes suitable for cultivation and breeding programmes. Methods: Twenty-five grasspea genotypes, including three check varieties, were evaluated during the rabi season of 2024–25 at Raipur, India. Three sowing dates (20 November, 1 December, and 10 December 2024) were considered as distinct environments, and the experiment was conducted in a randomised complete block design with two replications. Stability parameters were estimated using the Eberhart and Russell regression model based on mean performance, regression coefficient (bi), and deviation from regression (S²di). Results: Pooled analysis of variance revealed significant differences among genotypes, environments, and genotype × environment interactions for seed yield per plant. Significant genotype × environment (linear) interaction indicated differential responses of genotypes to environmental changes. The genotypes AKL-19, IFLA118-S4, IFLA220-S1, IFLA2441-S14, IFLA2750-S4, Mahateora, and IGC-2012-74/10-7-S9 exhibited superior mean yield, regression coefficients close to unity, and non-significant deviations from regression, indicating stable performance across environments. Conclusion: The identified stable genotypes demonstrated wide adaptability and consistent yield performance under varying sowing conditions, making them promising candidates for cultivation and utilisation in grasspea improvement programmes aimed at enhancing yield stability and productivity.