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研究结果表明 :(1)由于同源四倍体大白菜的花粉母细胞内Ⅰ、Ⅲ、Ⅳ型配对的同源染色体发生不规则分离 ,后期Ⅰ、Ⅱ部分染色体落后和向两极分配不均衡 ,致使后期Ⅱ形成染色体数目变化于 15～ 2 4的各类细胞 ,以染色体数为 2 0的细胞为主 ,其次是 19和 2 1的细胞。 (2 )具有 2 1条染色体的小孢子 (2x +1)再生植株能力与正常小孢子 (2x)再生植株能力相近。 (3)减数分裂的各种异常频率和三体株获得率品系间存在差异。
The results showed as follows: (1) Because the homologous chromosomes of type I, III and IV of the autotetraploid Chinese cabbage were irregularly segregated and the chromosomal backwardness and bipolar distribution in the late stage I and II were not balanced, As a result, the number of chromosomes varied from 15 to 24 in late stage II, and the number of chromosomes was 20, followed by 19 and 21, respectively. (2) Microspore (2x +1) plants with 21 chromosomes had the same ability to regenerate the normal microspores (2x). (3) There are differences between the frequencies of meiotic abnormalities and the rate of trisomy obtained.