秋水仙碱诱导栝楼四倍体

INDUCEMENT OF TETRAPLOID OF Trichosanthes kirilowii Maxim BY COLCHICINE

采用改良L.D.Cua法诱导短把栝楼获得四倍体,研究了0.2%浓度的秋水仙碱诱导短把栝楼染色体倍性变异的最佳处理时间、四倍体栝楼与原栝楼的形态特征及其四倍体与二倍体的细胞学鉴定。结果表明:0.2%秋水仙素的最佳处理时间为72 h,诱变率达82.1%。与二倍体相比,四倍体表现为:生长变缓;叶片增大、皱缩和变厚、叶形指数减小;叶片保卫细胞增大,气孔密度降低,叶绿体数目增加,叶色加深。根尖压片表明:二倍体的染色体数目为2n=66,大部分四倍体植株的染色体数目为2n=132,M2代部分四倍体植株也存在嵌合现象。

The improved L. D. Cua method was used to induce tetraploid of Trichosanthes kirilowii Maxim. The suitable treating time of 0.2% eolchicine, the morphology characters and cytology identification between plants of diploid and obtained tetraploid were studied. The results showed that 72h treating time could obtain variant rate of 82.1%. Comparing with diploid, the growing rate of tetraploid plants was slow and the leaves became bigger, thicker, dark green and crimpled. The stomata density of tetraploid plants was reduced, but the guard cell of stomata became bigger and the chloroplast number in guard ceils was increased. By chromosome observation of root tip cells, the chromosome number of diploid was 2n = 2x = 66, and the chromosome number of most tetraploid plants was 2n = 4x = 132. It was also found that some of tetraploid plants in M2 were chimera.