Development of a genetic marker linked to a new thermo-sensitive male sterile gene in rice (<Emphasis Type="Italic">Oryza sativa L</Emphasis>.)

Application of the thermo-sensitive genic male sterile (TGMS) system has a great potential to increase the efficiency of hybrid rice breeding. An indica rice TGMS mutant, 0A15-1, was crossed with a fertile indica line Guisi-8 to map the gene responsible to the TGMS. A RAPD (random amplified polymorphic DNA) maker, S187-770, linked to the TGMS gene at a distance of 1.3 cM in coupling phase was identified. The S187-770 was then cloned and sequenced to develop a dominant SCAR (sequence characterized amplified region) marker. Homology search against rice genome DNA sequence database indicated that S187-770 located on the short arm of chromosome 3 and close to centromere as a single copy sequence. This SCAR marker can be used in the marker-assisted transfer of this gene to different genetic background. As no other TGMS gene has been mapped on rice chromosome 3, the gene from 0A15-1 is a new TGMS gene and tentatively designated tms6(t).