Pollen Mother Cell Meiosis and Male Gametophyte Development of Brassica campestris ssp. chinensis Makino.

Chromosomal meiotic behaviors and male gametophytes development of non-heading Chinese cabbage were studied using chromosome preparation and fluorescence staining technique.The research showed that:the cytokinesis and chromosomes meiosis of pollen mother cells of non-heading Chinese cabbage was simultaneous type,and diakinesis bivalents was mostly rod and ring.A few lagging bivalents appeared in anaphase Ⅰ and the spindle arranged in vertical,parallel and the '八' like in metaphase Ⅱ.The microspores in tetrad stage showed the arrangement of decussate type,isobilateral type and tetrahedral type.Diakinesis,metaphase Ⅰ and metaphase Ⅱ was the best period for identification of chromosome numbers.Buds'length from 1.5 to 2.49 mm was usually at the stage of uniuclete microsore in center.Uniuclete microsore at periphery and early 2-celled pollen stage was related with buds between 2.5 to 3.0 mm long.2.0～3.0 mm long flower buds were adapted for anther or microspore culture.