Shoot regeneration from cotyledon of orange-heading Chinese Cabbage Cloning and sequencing of a specific DNA fragment related to cytoplasmic male sterility line of chinese cabbage(Brassica campestris ssp.pekinensis) Studies on High Efficient System for in vitro Shoot Regeneration from Hypocotyls of Chinese Cabbage RAPD analysis of CMS line and its maintainer line in Chinese Cabbage (Brassica campestris ssp.pekinensis)