Relationship between fertility alteration of fertility-changing sterile plant of nucleus male sterile line Kang A_1 and temperature in cotton

To get the homozygosis line of two-type nucleus male sterile line Kang A1 and enhance the sterile plant rate from 50% to 100%,the sowing date was adjusted and two fertility-changing sterile plants were found.Then the relationship between fertility alteration and temperature was studied.It was indicated that new temperature-sensitive male-sterile line cultivated from Kang A1 was sterile in low temperature and fertile in high temperature.The critical temperature of sterility transformation was 27～28℃ and the sensitive time was 7～13 days before blooming.The sterile plant rate of this nucleus sterile line was enhanced per-generation and it had reached 65% affter 3 generation of self-bred.Therefore,it would be homozygous in Zhanjiang.