盾叶薯蓣组织培养及四倍体诱导技术的初步研究

以盾叶薯蓣的茎段、叶柄、叶作为外植体进行离体组织培养，其效果以茎段和叶柄最好。诱导愈伤组织的培养基以MS+2,4-D 2.0mg/L+BA 0.5mg/L为佳；在培养过程中，可用MS+BA 3.0mg/L+NAA 0.2mg/L作为分化培养基，后逐步转为MS+BA 1.Omg/L+NAA 0.2mg/L作为继代培养基；生根培养可使用MS+NAA 1.0mg/L的培养基。在组织培养条件下，对盾叶薯蓣进行了多倍体诱导的研究。结果表明，用0.15%的秋水仙素处理24小时后，诱导率可达50%，效果较好。经秋水仙素诱导的变异株，与正常的二倍体植株相比，植株粗壮，叶片变大变厚，叶色浓绿，部分还出现畸形叶。叶片表皮气孔检测发现，多倍体植株叶片表皮气孔变大，且单位面积下的气孔数目减少；进行细胞学研究发现，正常植株的染色体的数目为2n=2x=20，变异植株染色体数目为，变异植株染色体数目为2n=4x=40,为四倍体。

Preliminary Study On Polyploid of Dioscorea Zingbernisis In Vitro

Using the stems,leafstalks,leaves of Dioscorea Zingbernisis as the explants in tissue culture, the result shows that stems and leafstalks are the best. The best culture medium of callus induction is MS 2,4-D 2.0mg/L BA 0.5mg/L;The differentiation on culture medium is MS BA 3.0mg/L NAA 0.2mg/L;The subculture medium is MS BA 1.0mg/L NAA 0.2mg/L;Root medium is MS NAA 1.0mg/L.Tube seedings of Diosocrea Zingibernisis were treated with colchinine. The result shows that the best induction rate could reach 50% after treatment with 0.15% colchcine in 24 hours.Compared with the polyploid plants were thicker and larger. A few leaves appeared malformed.The stoma become larger and less in number. Cytological study show that the chromosome numbers of variation is 40,that of normal diploids is 20.