Performance, adaptability, and multi-trait stability of rice varieties (Oryza sativa L.) in rainfed conditions

Abstract

Rainfed rice (Oryza sativa L.) cultivation is crucial for meeting food demand in regions like Bangladesh, where irrigation resources are scarce. A study was conducted in five rainfed districts during the 2022 Aman season. The objective was to assess grain yield performance, adaptation patterns, and identify a stable rice variety using multiple trait evaluations. The results showed that Binadhan-17 produced the highest grain yield, reaching 5.58 t/ha, with its maximum yield recorded in Gopalganj at 6.12 t/ha. Heritability estimates from a linear mixed model were high for plant height (0.93) and grain yield (0.65), with genotypic variance contributing 92.70% and 64.84% to these traits, respectively. A negative correlation (r = −0.43) indicated that shorter varieties tend to perform better for grain yield. Stability analysis using weighted average absolute scores and best linear unbiased prediction identified Binadhan-17 as the most stable for grain yield, while the genotype–genotype environment biplot confirmed its adaptability across all locations. Factor analysis of the multi-trait stability index showed stability across traits, with selection gains from 1.49% to 6.99%. Binadhan-22 was identified as the most stable for average performance and multi-trait stability. Given its high yield and consistent performance across environments, Binadhan-17 is recommended for large-scale cultivation, while Binadhan-22 offers a reliable, stable alternative across various traits.