Identification of drought tolerant restorer lines and association between pollen fertility and spikelet fertility in cms based rice (oryza sativa l.) hybrids

Hybrid rice systems are based on three line Cytoplasmic Male Sterility (CMS) which has been an efficient tool in commercialization of hybrid rice technology. Therefore, identification of potential restorers in rice is the basic step in development of rice hybrids. In the present study, 70 drought tolerant lines were crossed with two cytoplasmic male sterility lines viz., IR58025A and IR79156A and the F1s were analyzed for pollen fertility (1% I-KI Solution) and spikelet fertility. Based on the fertility restoration in F1s, 23 genotypes were classified as restorers with IR58025A and 25 genotypes were classified as restorers in IR79156A. Highly significant correlations of 0.88 and 0.93 between pollen and spikelet fertility were obtained in hybrids involving CMS line IR 58025A and CMS IR 79156A respectively. KMR 3, IR 84891-B-112-CRA-15-1 and IR79906-B-192-2-2 produced F1s with highest pollen and spikelet fertility and are considered as the most promising restorers.