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１９９１～１９９３年连续分析了２套大白菜异源胞质雄性不育系ＣＭＳ３４１１－７及ＣＭＳ７３１１不同转育材料的核型，并做了细胞学观察鉴定。发现转育４代和９代具甘蓝型油菜胞质的大白菜胞质雄性不育系，核内染色体数目均为２ｎ＝２０，但２个不育系的核型都程度不同地与相应保持系存在差异，主要表现在随体染色体的大小、位置、数目，近中部着丝点染色体的多寡，染色体的臂比值等方面。说明在回交转育过程中，白菜染色体（ａａ）同油菜染色体（ａａｃｃ）发生了一定的交换或易位。细胞学观察表明，２套不育系花药败育时期均在孢原细胞形成之前，只有极少数花药中的１～３个花粉囊可以发育到四分体或单核花粉期，且大小极不一致，表现特大或特小，说明其不育性比较稳定、彻底。
From 1991 to 1993, the karyotypes of two CMS lines, CMS3411-7 and CMS7311, were analyzed in succession and cytologically observed. The cytoplasmic male sterile lines of Chinese cabbage with 4 and 9 generations of Brassica napus were found to be 2n = 20 in chromosome number, but the karyotypes of the two lines were all different from each other There are differences, mainly in the chromosome size, location, number, near the central centromere chromosomes, chromosome arm ratio and so on. This indicated that during the process of backcrossing, cabbage chromosome (aa) and rape chromosome (aacc) had some exchange or translocation. Cytological observations showed that only two or three anther abortive stages of sterile male sterile anthers could develop to tetrad or mononuclear pollen stage before the formation of sporogenous cells, , Showing large or small, indicating that its sterility more stable and thorough.