用20℃的低温对GB028S分别处理1,3,5,7d,研究不同低温时长对粳型光温敏核不育系育性转换的影响。结果表明:低温使各处理抽穗期滞后2～8d。1d和3d的低温处理下,GB028S花粉不育度大于99.5%,育性没有转换;5d和7d的低温处理下,GB028S的花粉不育度为98.33%和94.33%,自交结实率为2.64%和5.04%,育性恢复。GB028S的临界温度接近20℃,其低温敏感时期的辨别标准为剑叶叶枕距-3～1cm。 The effect of different low temperature duration on the fertility transformation of Japonica Photo-thermo-sensitive Genic Male Sterile (CMS) lines was studied after treated with GB028S at low temperature of 20 ℃ for 1, 3, 5, and 7 d, respectively. The results showed that: low temperature made the treatment of heading date lag 2 ~ 8d. The pollen sterility of GB028S was over 99.5% at 1d and 3d, and the fertility did not change. Under the low temperature treatment of 5d and 7d, the pollen sterility of GB028S was 98.33% and 94.33%, and the selfing rate was 2.64% And 5.04%, fertility restoration. GB028S critical temperature close to 20 ℃, the low temperature sensitive period of discrimination criteria for the flag leaf pillow from -3 to 1cm.