Cross and continuous back-cross were made between sterile line of Chinese cabbage 12A, which was bred with CMS Shan 2A in Brassica napus. L., and self-bred line of non-heading Chinese cabbage. In BC 4,sterile line Qing 1A and Qing 2A were selected, and their sterile rate reached to 100%, and their sterile degree was over 95% and their character was stable. Their hybrids Qingza No.1 and Qingza No.2 and Qingza No.3 were gotten through test crossing. The result of varieties test for continuous 2~3?a showe...