Identification of promising aerobic rice genotypes through Aerobic Response Index, stability analysis and participatory varietal selection

Twelve rice genotypes (including three checks) were evaluated under aerobic conditions using a randomized complete block design with three replications under farmers’ field in four locations. GE interaction was analyzed using linear regression techniques. There was considerable variation for grain yield among both genotypes and environments. The regression coefficient of cultivar Pyari (CR 2624) was almost unity and had one of the lowest deviations from regressions with high coefficient of determination, confirming its stability. In contrast, genotypes IR 78875-53-2-2-2 and IR 78878-53-2-2-4 showed insensitivity to environmental changes for grain yield. Low and consistent Aerobic Response Index (ARI) also confirmed their stability. Genotypic variation in ARI was consistent for tested genotypes among all the farmers’ field. The mean values of ARI for grain yield (GY) were less than 1, which indicated the relative tolerance of this character under this study. The significant and positive correlations were obtained between ARI and GY under favourable condition (irrigated), whereas, negative association in unfavourable (aerobic) condition. Three genotypes namely, Anjali, Lalat and IR 79906B-5-3-3 were identified as inconsistent on the basis of performance of ARI, over the locations (farmers’ field). The inconsistence of the estimates in ARI across farmers’ field, reflects high G x E interactions for grain yield under aerobic condition. In this context, Pyari (CR 2624), IR 78875-53-2-2-2 and IR 78878-53-2-2-4 may be suggested as stable genotypes for target area during dry season. Involvement of the clients (farmers) in the breeding and selection process would be immensely helpful in selecting genotypes, that is expected to combine higher grain yield with other requisite parameters for the farmers, in irrigated/lowland rice with water scarcity.