Fine mapping and expression analysis of thermosensitive genic male sterility gene (tms) in rice (Oryza sativa L.)

Abstract

Thermosensitive genic male sterility (TGMS) is a most comfortable type of male sterility for the production of two-line hybrids in rice. In TGMS system, genes responsible for male sterility and its reversibility is of great importance to create a new pathway for development of new male sterile lines in rice. In this study, genetic analysis based on F2 population derived from a cross between TNAU 60S and IET 21009 revealed that a single recessive gene controls male sterility in TNAU 60S. Marker analysis combined with bulked segregant analysis (BSA) was used and located the target gene on chromosome 2. Fine mapping with 86 SSR markers on chromosome 2 between 20.0 cM and 27.0 cM revealed that tms gene is located at 24.3 cM between two SSR markers RM12713 and RM12722. Among the six genes, two genes LOC_Os02g12420 and LOC_Os02g12680 which encodes receptor like kinase and cytochrome P450 respectively were considered as candidate genes for thermosensitive gene male sterility in TNAU 60S because of very high differential expression between sterile and fertile samples.