基于ITS与trnL-F序列探讨槭树科的系统发育(英文)

Phylogeny of Aceraceae Based on ITS and trn L-F Data Sets

报道了槭树科 4 1种 (其中槭属 39种 )植物的trnL_F和ITS序列 (其中部分种的ITS序列为重新测定 ) ,以期通过分子手段对槭树科内部尤其是复杂的槭属的系统发育关系进行重建。以无患子科和七叶树科为外类群 ,基于对 5 7个种单独的ITS序列 (包括从GenBank下载的 16种的序列 )、4 1种trnL_F序列及 4 1种两者序列的联合数据 ,分别采用最大简约法 (MaximumParsimonyMethod)和邻接法 (Neighbor_JoiningMethod)对槭树科的系统发育进行了分析。结果显示 ,整个槭树科为一单系类群 ;金钱槭位于槭树科的基部 ;但由于云南金钱槭 (Dipteroniadyerana)聚在了槭属内部 ,认为金钱槭属和槭属均可能是非单系类群 ;槭属内组间关系的支持率普遍较低 ,但多数组的组内关系得到了较好的支持。将两个片段结合比单独的ITS或trnL_F分析能更好地解决槭属内部的系统关系 ,其中sect.Palmata和sect.Microcarpa ,sect.Platanoidea、sect.Lithocarpa和sect.Macrophylla ,sect.Integrifolia、sect.Trifoliata和sect.Pen taphylla ,以及sect.Acer、sect.Goniocarpa和sect.Saccharina (sensuOgata)的组间亲缘关系得到了一定的支持 ,但对其中部分组的划分可能应做进一步调整。重新评价了徐廷志系统中对sect.Rubra和sect.

The nuclear encoded internal transcribed spacer (ITS) region and the plastid encoded trn L-F region were sequenced for 41 species of the Aceraceae, representing both genera Acer and Dipteronia, to reconstruct phylogeny of this family, especially within Acer. The analyses were performed in separate and combined sequence data sets, with the Sapindaceae and Hippocastanaceae being selected as outgroups. It was indicated that the Aceraceae was monophyletic and D. sinensis was basal to the rest of the family but the two genera of it might be not monophyletic because Dipteronia dyerana was nested within Acer. The result inferred from the combined data showed greater resolution within Acer than that from the two separate data sets. The monophyly of most sections in Xu's system (1996) were supported with high bootstrap values, and some relationships between (or among) sections were also inferred, such as sect. Palmata and sect. Microcarpa; sect. Platanoidea, sect. Lithocarpa and sect. Macrophylla; sect. Integrifolia, sect. Trifoliata and sect. Pentaphylla; and sect. Acer, sect. Goniocarpa and sect. Saccharina (sensu Ogata). However, the sectional status and circumscriptions of some of the above-mentioned sections should be further adjusted. It seemed that the Xu's delimitations of sect. Rubra and sect. Saccharodendran should be revaluated.