Response of fertile pollen grains to different temperatures and cytological base of male sterility in TemianS-1

The cotton line TemianS-1 was a recently developed male sterility sensitive to high temperature.In vitro study showed that pollen germination and pollen tube length of TemianS-1 were less than that of Sumian16 under all temperature treatments(15,20,25,30,35,and 40 ℃).The maximum pollen germination and pollen tube length of TemianS-1 were 37% and 450 μm,respectively,and significantly lower than that of Sumian16(51.8% and 682 μm).Under high temperature conditions,the pollen female cells were not formed in anthers in a few young buds and normal tetraspores were hardly developed after meiosis processes in most young buds,which was the main reason for male sterility of TemianS-1.