Effect of temperature on fertility conversion of a thermo-sensitive genic male sterile line of non-pollen type XianS in rice(Oryza sativa L.)

XianS is a thermo-sensitive genic male sterile line of non-pollen type in rice and a mutant from traditional variety Xianhuangzhan.In Guangzhou,XianS expressed strongly the character of fertility alternation from fertility to sterility then to fertility.The fertility changes were mainly affected by temperature.The analysis of correlation between fertility and the highest temperature,lowest temperature,the average temperature showed that the sensitive stage to high temperture calculated with lowest temperature was the longest,23～10 d before heading,reaching 14 d;and the sensitive stage to low temperature calculated with lowest temperature was the longest,24～16 d before heading,only 9 d.The initial date of the sensitive stage to high temperature and that to low temperature are roughly the same,but the ending date was later for the sensitive stage to high temperature.Under the photoperiod of 13.5 h,the temperatures of 24 ℃ and 24.5 ℃ could lead to sterility of XianS.