Abstract: Among the descendants plants of the cross 83(1)-44/3/Chun18/Bau//Seri a sterile plant was discovered. It was primerly predicted that light and temperature affected the sterilty through the tests of dividing the period to sow seeds. the low temperature maily resulted in the sterilty, and light length also affected the sterilty . At short light the selfed seed fertility ratio went down, at long light went up. Seed fertility descend that low temperature resulted in couldn't be compensated by the adding light times. But seed fertility descend that short light resultede in could be be compensated by the raising temprerture.