CRISPR/Cas9-mediated editing of the thermo-sensitive genic male-sterile gene <italic>TMS5</italic> in rice

Abstract

Thermo-sensitive genic male-sterile (TGMS) gene tms5 is most widely used in the two-line hybrid breeding system in China. To develop novel rice thermo-sensitive male sterile lines, we knocked out the TMS5 genes of six elite japonica and four indica rice varieties by using CRISPR/Cas9 gene editing technology. By analyzing the critical sterility-inducing temperature (CIST) of the newly TGMS lines, it was found that the CIST of japonica TGMS lines ZG75S, CYGS, YG0618S, ZG07S, T0361S, and 7679S were between 28°C and 32°C, the CIST of indica TGMS lines 2537S, 6150S and 6379S were between 24°C and 28°C, and the CIST of indica TGMS line 1109S was lower than 23.5°C. These results indicated that the CIST of tms5 mutant from different genetic background materials was different. The TGMS lines with lower CIST could be obtained by knocking out the TMS5 from different genetic background materials. A hybrid rice combination 1109S / 8048 had high quality and high yield. The yield of 1109S/8048 was 13.1% higher than that of Fengliangyou 4. The creation of the TGMS 1109S and the high-yield cross combination 1109S/8048 provides a new way for high-yield breeding.