秋水仙碱诱导枣多倍体的研究

Studies on Polyploid Induction of Chinese Jujube with Colchicine

以冬枣、临猗梨枣和辣椒枣一年生嫁接苗为试材 ,以秋水仙碱为诱变剂诱导多倍体。结果表明 :临猗梨枣诱变率最高可达 5 0 %,最佳组合为 0 1 5 %秋水仙碱处理茎尖 1 8h ;冬枣和辣椒枣的诱变率最高可达 4 3 3%,最佳处理组合分别为 0 1 %/30h和 0 1 5 %/1 8h。变异材料的细胞染色体数 (2n =4x =4 4 )和单细胞DNA含量均为二倍体对照的 2倍 ,在辣椒枣中还出现了染色体数为 2n =2x +2 =2 6及DNA含量为八倍体的细胞。四倍体变异材料均表现出叶长、叶宽、叶面积增大 ,叶形指数减小 ,节间长度变短等特征。另外 ,还表现出叶片气孔保卫细胞增大 ,叶绿体增多 ,花粉粒增大 ,畸形花粉增多 ,四孔沟花粉出现及花粉粒育性降低等。

One year old grafted seedlings of Ziziphus jujuba Mill. cv. Dongzao, Linyilizao and Lajiaozao were treated with colchicine at the shoot-tip. The results indicated that the highest induction rate of Linyilizao was 50% with optimum treatment combination of 0.15%/18h; the highest induction rates of Dongzao and Lajiaozao were both 43.3%, and the optimum treatment combinations were 0.1%/30 h and 0.15%/18 h respectively. The chromosome number of the shoot-tip of the mutated plants (2 n=4 x=44) and the DNA content were both twice that of the control. In addition, the chromosome number of some mutated Lajiaozao was 2 n=2 x+2=26,and some octoploid cells were found in mutated Lajiaozao. The leaf length, width and area were larger and the leaf index, internode length were smaller than those of the diploid plants. The induced polyploid materials also showed larger stomatas, more chloroplasts, and larger but more deformed pollens. The decrease of pollen fertility and some tetracolporated pollens were also observed.