红豆杉科及相关类群rbcL基因PCR—RFLP分析

运用RFLP方法对红豆杉科及相关类群14种植物叶绿体rbcL基因PCR产物进行限制酶酶切分析，共获29个酶切变异位点。采用PHYLIP软件包对限制位点变异数据进行极大简约法分析得到18个步长为6的最简约树并求得一致树，结果显示：⑴红豆杉科和三尖杉科属单系群；⑵穗花杉属Amentotaxus以置于红豆杉科内为宜，不支持将穗花杉属独立成科的处理方式；⑶白豆杉应为红豆杉科内一个属Pseudotaxus；⑷三尖杉属内篦子三尖杉地位特殊，可设篦子三尖杉组；⑸不赞同将竹柏类从罗汉松属中分离出去成立新科；⑹红豆杉科、三尖杉科和罗汉松科三者间，前两者的关系更为接近。

PCR-RFLP Analysis of rbcL Genes in Taxaceae and Related Taxa

PCR_RFLP analysis of rbcL genes in the Taxaceae and related taxa was conducted by using 10 restriction enzymes to digest the gene fragments amplified from 14 representative species. 29 restriction sites were identified as polymorphic. To reconstruct a molecular phylogeny PHYLIP package was employed to analyse the restriction site data for determining the most parsimonious tree by maximum parsimony method. 18 most parsimonious trees as well as their consensus tree were calculated out. The results imply 1) that the Taxaceae and the Cephalotaxaceae are monophyletic groups; 2) that the genus Amentotaxus is better to be included in the Taxaceae than to be treated as a separate family; 3) that the generic status of Pseudotaxus in the Taxaceae is supported; 4) that in the Cephalotaxaceae the establishments of Sect. Cephalotaxus and Sect. Pectinata are rational; 5) that it is questionable to separate nageiaoids from Podocarpus to establish a new family Nageiaceae; 6) that the Cephalotaxaceae and the Taxaceae than to the Podocarpaceae are more closely related.