Genotype‐by‐Environment Interaction Influenced the Crude Protein and Total Amino Acid Content in Lentil Varieties

Lentil ( Lens culinaris Medik.) is a globally important grain legume valued for its high‐protein content and nutritional quality. However, the genetic and environmental factors influencing protein and amino acid composition, particularly the role of genotype × environment interaction (GEI), remain partially uncovered. This study evaluated 15 diverse lentil genotypes across seven agronomic trials spanning multiple years, sowing seasons, and locations to assess the effects of genotype, environment, and GEI on crude protein (CP), crude protein yield (CPY), total amino acids (TAA), and total amino acid yield (TAAY). Advanced statistical models such as Additive Main Effects and Multiplicative Interaction (AMMI), Genotype plus Genotype‐by‐Environment (GGE), and Weighted Average of Absolute Scores (WAASB) were employed to dissect the contributions of genetic and environmental components and to identify stable, high‐performing genotypes. Results revealed significant phenotypic variation for CP, amino acids (AA), and TAA among genotypes. Seasonal variation, especially between autumn and spring sowings, was the primary environmental driver of GEI for both CP and CPY. Notably, some landraces (PI_431710_LSP, PI_431739_LSP, PI_431753_LSP, and IG_1959) demonstrated both high productivity and stability across environments, while others excelled in specific mega‐environments identified through GGE analysis. Our findings emphasize the importance of integrating into lentil breeding programs, stability and adaptability, and a more comprehensive approach to measure the yield (e.g., CPY, MegaJoule, amino acid composition, and TAAY), which takes into account the quality and the effective energetic production of a crop. From this perspective, we highlight landraces as valuable sources of genetic diversity for improving yield. This work provides a foundation for targeted breeding strategies aimed at developing lentil varieties with enhanced protein content, balanced amino acid profiles, and resilience to environmental variability.