Study And Application Of Reverse Thermo-sensitive Genic Male Sterility Controlled By Sa Locus In Rice (Oryza Sativa L.)

Photoperiod/Temperature-sensitive genic male sterile(PTGMS) is a typical ecological phenomenon, which is controlled not only by male sterile genes but also by ecological conditions such as photoperiod and temperature. The discovery of PTGMS rice established the new way to utilize heterosis of rice. The hybrid sterility gene Sa have been cloned. Our laboratory has found a reverse thermo-sensitive genic male sterility(RTGMS)rice line G392 S, which is sterile under low tempreture condition and fertile under high tempreture condition. This phenotype is controled by recessive single-locus rtms2(ORF13)adjacent to Sa.The molecular mechanism underlying RTGMS was investigated by CRISPR/Cas9 system and following results were obtained.1. Simulating natural temperature, when the average temperature was 30.6 ?, G392 S pollen fertility were restored, when the average temperature was 31.83 ? time, G392 S pollen fertility were significantly restored.2. CRISPR/Cas9 vector of Sa F, Sa M, ORF13 were constructed and transformed into G392 S plant respectively, and the positive plant was obtained.3. After low temperature treatment on homozygous mutants G392 S, fertility of pollen and spikelet went recovered to normal. These results further improve the molecular mechanism of RTGMS controlled by three gene/four-component.4. Many improved indica lines of RTGMS were obtained. RTGMS controlled by three genes were inserted into the improved indica varieties by backcrossing,The results of target gene knock-out by CRISPR/Cas9 technology provide proofs for the “three gene/four-component interaction model for RTGMS” and many improved indica lines of RTGMS were obtained.