温度对无花粉型水稻温敏核不育系籼S育性转换的影响

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

通过对自然突变的无花粉型水稻温敏核不育系籼S进行育性转换的试验发现，籼S在广州具有明显的“可育-不育-可育”的育性转换特性，其育性变化主要受温度影响．利用自然条件下日最高温、最低温、平均温与籼S的花粉育性进行相关性分析，结果表明，高温不育敏感期以平均温推算的最长，为抽穗前的第23—10d，可达14d；而低温可育敏感期则以最低温推算的最长，为抽穗前的第24—16d，仅9d，高、低温敏感期的起始日期基本相同，但高温敏感期的截止日期要晚．13．5h的光长，24℃、24．5℃的温度均能导致籼S败育．

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.