Aerobic response index and diversity analysis for identification of aerobic rice donors

Thirty six rice genotypes were evaluated to identify promising aerobic donors for eight quantitative characters. The analysis of variance revealed significant differences among the genotypes, environments and genotypes x environments. High phenotypic (PCV), genotypic (GCV) coefficient of variation and high heritability along with high expected genetic advance were recorded for grain yield and biological yield. Grain yield and biological yield had positive correlation for all the characters except days to fifty per cent flowering. Higher and positive direct effect on grain yield was exerted by biological yield, tillers hill⁻¹ and grains panicle⁻¹. The D² analysis revealed that genotypes exhibited considerable diversity and were grouped in to six clusters. Based on clustering pattern, aerobic response index and stability factor of the genotypes, eight genotypes would be served as donors and can be include in combination breeding to improve drought tolerance of existing rice varieties.