Abstract

To evaluate the varietal stability of rice grown under irrigated conditions, trials were conducted on thirty-four rice varieties across two locations. The objective of this study was to examine the impact of genotype × environment interactions (GEI) on high-yielding rice varieties. The primary focus was on the attributes of the rice varieties and their yield potential. Clustering methods were employed to determine the most effective way to group the varieties based on the key attributes of interest. Subsequently, the AMMI and additive main effects models were used to assess GEI and identify the varieties that would perform best under different conditions. Eight groups were formed, three of which were identified as the best, grouping varieties with the highest yield, the shortest plant height at maturity, the fewest days to maturity, and the best harvest index. Nine genotypes exhibited greater stability, with the high-yielding varieties standing out. While some varieties performed well in specific environments, the multi-trait stability index highlighted the most adapted rice varieties, FAROX 508-3-10-F43-1-1 and WAB 1491-5N-B-FKR3-WACB, based on their performance across all studied environments. However, these varieties, except for WAB 2066-6-FKR4-WAC1-TGR1-B-WAT-B9 (9.51 t×ha-1), did not rank among the top yielders, despite producing rice grain yields ranging from 8.27 t×ha-1 to 8.96 t×ha-1, results that are still significant.

Key words: Multilocation trials, AMMI, rice, varietal selection, varietal stability, yield.