Mapping of a Novel Gene for Semi-sterility in Rice (Oryza sativa L.)

Abstract

A spontaneous semi-sterile mutant, found from a japonica rice variety Nipponbare, shows pollen and spikelet semi-sterilities. On the basis of genetic analysis with reciprocal F₁ hybrids between the mutant line W207-2 and a wide-compatibility rice variety CPSLO17, the semi-sterility was found to be controlled by a recessive nuclear gene ss-1(t). A linkage map was constructed to determine the locus for the semi-sterility gene, using an F₂ population of W207-2/CPSLO17. Through linkage analysis it was found that the gene was located between SSR markers RM152 and RM6863 on chromosome 8, with map distances of 6.3 cM and 8.8 cM, respectively. The finding of the new sterility gene will be useful for handling semi-sterility mutants in seed production and for understanding the genetic mechanisms of spikelet fertility in rice.