The Genetic Analysis And Mapping Of The Recessive Genic Male Sterility Gene Of Rice

The male sterility is the basics of the utility of heterosis in hybrid rice. In 1964, Yuan Long-ping found the first male-sterile plant in the Dongting early Indica, which created the new century of the hybrid rice research in China. In this 21th century, the hybirid rice will still be the most important approach of food yield increase. Male sterility and heterosis is the hot-point in the rice research field at home and abroad. We can improve the yield and quality of rice through finding out the male sterility mechanisms and researching the male-sterile genes.In this research, The plant material selected was a mutant male sterility. It was found by Sichuan Agricultural University Rice Research Institute in Lingshui, Hainan Province. It can be named as Sichuan recessive genic male sterility (H₂S). The F₁ and F₂ of the crosses was between H₂S and Zhenshan-97B along with some other materials. Their male-sterile characters was studied by the genetics analysis, at the same time, the recessive genic male sterility gene was mapped by SSR molecular marker. The main results are summarized as bellows:The F₁ in lots of combinations are fertile, but in F₂, 3/4 are fertile, 1/4 are sterile. In the different genetic background, phenotypic is consistent, and it will not be affected by the photo and temperature. It showed that this male-sterile was controlled by a pair of recessive gene.The cytological observation of F₂ anther proved this male-sterile belonged to the none-pollen type.According to the result of genetic efficiency analysis, the male-sterile plant has the longer growth duration, two days than fertile one; the lower height, about 4 cm than fertile one; the smaller seed set, about 23 panicles than fertile one .And the male-sterile plant has more about 8 tilling number than fertile one.According to the result of genetic analysis and bulked segregant analysis inthe F2 of H2S and Shan-B population were used to screen rice SSR molecular marker linked with the male sterility gene. The results showed that the marker RM3, RM454, RM528 in chromosome 6 is linked with the target gene. Their genetic distance is 16. 1 cM, 7. 5 cM, 9. 2 cM. This mapping by SSR molecular marker was not reported till now, it was named as ms(t).