籼稻光（温）敏不育系新光S育性转换的光温反应

 新光S是与农垦58S不同来源的具育性转换特性的不育系。对其育性转换的光温反应特性研究结果表明，该不育系在15.0 h长光照与所有处理温度（平均温度30.1℃、24.1℃和23.1℃）的光温组合下和30.1℃高温与所有处理光照时间（15.0 h、14.0 h和12.5 h）的光温组合下，表现完全不育；在14.0 h与23.1℃和24.1℃的光温组合下，育性部分恢复；仅在12.5 h短光照与23.1℃和24.1℃的光温组合下，育性才趋于正常。对自交结实率的两因子方差分析表明，单独的光周期效应和温度效应均不显著（p＞0.05），仅光温互作效应达极显著水准（p＜0.01），属典型的光温互作型。在杭州自然条件下，新光S表现出较长（约2个月）的稳定不育期，但秋季繁殖的结实率未达到在人工气候箱的短日低温下的结实率水平。对新光Ｓ这类光温互作型籼型不育系的实用价值作了评价。

Response to Photoperiod and Temperature in Photo-thermoperiod Sensitive Genie Male Sterile Line Xinguang S(Oryza sativa L.subsp.indica)

Xinguang S is a male sterile indica rice line with fertility transformation, its origination is different from Nongken 585, a reported photoperiod sensitive genic male sterile rice line. The response of Xinguang S to photoperiod and temperature was studied in the controlled conditions of 3 photoperiods×3 temperatures in combination with in the natural condition of 10 planting dates with the interval of 15 days. The results indicate that the fertility transformation of Xinguang S is controlled by interaction of photoperiod and temperature. It will be completely male sterile under the combinations of 15.0 h photoperiod with all treated temperatures (mean temp. 30.1℃, 24.1℃ and 23.1℃) and 30.1℃ with all treated photoperiods (15.0 h, 14.0 h and 12.5 h), partially male sterile under the combinations of 14.0 h with 23.1℃ and 24.1℃,and normally male fertile only under the combinations of 12.5 h with 23.1℃ and 24.1℃. The variance analysis on the seed setting of Xinguang S indicate its photoperiod(P) or temperature(T) effect is not significant (P>0.05), but its P×T effect is sighficant(P<0.01). Its male sterile period may be two months in summer season under natural conditions of Hangzhou, however, its fertility transformation in autumn may be incomplete due to the unusually high temperature. The use of P×T type male sterile rice line such as Xinguang S in the breeding of two-line hybrid rice was evaluated.