秋水仙素离体诱导金线莲多倍体的研究

染色体加倍的试验结果表明,金线莲在秋水仙素浓度为300 mg/L(含有2%DMSO)时,茎节相对于顶芽受到更明显的抑制作用。随着处理时间的延长,秋水仙素对外植体的毒害作用加强,表现为外植体死亡率增多。300 mg/L的秋水仙素处理3～19 d均可导致材料的染色体加倍,处理13 d时,细胞染色体完全加倍率达到最大，为72.7%；细胞学鉴别结果显示金线莲的染色体数40条,加倍后的植株染色体数80条。四倍体的气孔大小明显比二倍体的大,二倍体和混倍体的气孔大小差异不显著。

Polyploidy in Anoectochilus roxburghii induced by colchicine in vitro

Explants of Anoectochilus roxburghii were adopted and treated with 300 mg·L_-1 colchicine for doubling the chromosome number. As the treating time being prolonged, the toxic effect of colchicine became more evident because the death rate of explants increased. Tetraploid cells were induced from the experiments when the explants were treated with colchicine at this level for 3-19 days. The best chromosome doubling results of 72.7% tetraploid cell frequency and 91% induction rate were obtained when explants were treated for 13 days. The number of chromosome of diploids and tetraploids were 40 and 80, respectively. The stoma size of tetraploids was larger than that of diploids. No difference was found between the stoma size of diploids and mix-ploids．