From landrace diversity to promising germplasm for rabi sorghum breeding: unravelling the multi-environment and multi-trait potential of Maldandi sorghum

Maldandi is an important genetic resource for post-rainy season (rabi) sorghum improvement in India, yet much of the diversity retained within this landrace complex remains underutilized in breeding programs. The present study evaluated 136 Maldandi sorghum landraces across three contrasting rabi environments—Rahuri, Solapur, and Dharwad—to assess their phenotypic diversity, environmental responsiveness, yield stability, and multi-trait breeding potential. Ten quantitative traits were evaluated using a combination of genetic parameter analysis, correlation, principal component analysis, hierarchical clustering, AMMI, GGE biplot, and multi-trait genotype–ideotype distance index approaches. Significant genotype effects were detected for all traits, while genotype × location interaction was significant for nine of the ten traits, highlighting strong environmental influence on landrace performance. Panicle exertion showed comparatively consistent expression across environments, whereas grain and fodder yield were more strongly affected by environmental conditions. Grain yield was positively associated with panicle weight and fodder yield, indicating opportunities for simultaneous improvement of grain and fodder productivity. PCA revealed that the first four components accounted for 83.59% of the total phenotypic variation, while hierarchical clustering separated the landraces into two major, unequally sized groups, indicating substantial and continuous phenotypic diversity within the collection. AMMI and GGE analyses demonstrated distinct patterns of environmental sensitivity for grain and fodder yield, with different landraces showing superior performance and stability across environments. Integration of grain yield, fodder yield, and their BLUP-based estimates through MGIDI identified 20 promising landraces, with IS4578, EP112, and PU31 ranking highest. The selected landraces represented complementary combinations of grain productivity, fodder productivity, and environmental stability rather than simply the highest-performing entries for a single trait. These findings indicate that the Maldandi landrace complex harbors substantial exploitable variation for productive, dual-purpose rabi sorghum improvement. The evaluation was conducted at three locations during a single rabi season and therefore primarily reflects spatial performance and genotype × environment responsiveness. The identified landraces provide promising donor resources for broadening the breeding base of rabi sorghum; their stability, adaptability and breeding value require validation across additional years and environments before wider recommendation.