Identification of maintainer lines and validation of SSR markers for development of new rice hybrids for aerobic situation

In order to expand the potential of three line hybrid rice breeding technology for aerobic condition, a study was carried out to identify potential restorer and maintainers suitable for aerobic condition. 72 hybrids were developed using nine newly developed quasi-CMS lines and eight elite lines were evaluated for pollen and spikelet fertility. Results revealed that 62 were found to be completely male sterile and 10 were found to be partial sterile. Among the eight testers used, six acted as maintainers for all the CMS lines and remaining two differed in restorability with respect to CMS lines. Simultaneously validation of SSR markers-linked to Rf locus was carried out on eight testers by comparing with standard maintainer and restorer type marker alleles. In the present study six new maintainer genotypes viz., P23-5-6, P23-5-28, P23-5-236, Rasi, HPR565 and HPR2278 were identified which can be further developed into new CMS lines. Among the seven markers used for validation of Rf locus RM 6100, RM171, RM 1008 and RM6344 were found to be perfectly co-segregating with phenotype. Hence, these are potential markers for selection of maintainer and restorer genotypes for newly developed CMS lines.