岛衣型真菌属级分类的初步研究

A PRELIMINARY STUDY ON GENERIC DELIMITATION OF CETRARIOID FUNGI

本研究对岛衣型真菌Allocetraria ambigua，Allocetraria stracheyi，Nephromopsis pallescens和Tuckneraria laureri的核rDNA ITS序列进行了测定，并结合来自Genbank中的其它21种岛衣型真菌的核rDNA ITS序列进行了同源性分析。分析所用软件为DNAMAN。结果发现，Cetraria、Allocetraria、 Vulpicida、 Flavocetraria、 Tuckermannopsis和Kaernefeltia之间rDNA ITS的同源关系非常密切。这同岛衣型地衣现有细分的小属观点相矛盾。这种矛盾可能是由于持小属观点的作者在分属时对个别表型性状加权的结果。

The nuclear rDNA ITS of cetrarioid fungi, Allocetraria ambigua，Allocetraria stracheyi，Nephromopsis pallescens and Tuckneraria laureri, are sequenced. The homology tree of the rDNA ITS of the four species mentioned above and those of the other 20 species of cetrarioid fungi from Genbank are analyzed with DNAMAN (version 4.0). Cetrelia cetrarioides is treated as outgroup in the analysis. The homology tree showed that the genetic distance among the Cetraria, Allocetraria, Vulpicida, Flavocetraria, Tuckermannopsis and Kaernefeltia is very close to each other. It seems that this situation does not support the current narrowly generic delimitation of cetrarioid fungi.