张玉霄  博士，导师：李德铢  研究员

论文题目：温带木本竹类的系统发育和网状进化——以青篱竹属群为主

摘要： 温带木本竹类是竹亚科中一个形态多样化明显并有着复杂分类历史的类群，而青篱竹属群是温带木本竹类中系统关系比较复杂的类群之一，呈典型的东亚—北美间断分布。通过大量的野外补点采集和观察，本文收集了温带木本竹类中的24属124种研究材料，利用8个叶绿体非编码区片段以及核基因GBSSI序列数据，以青篱竹属群为主，重建温带木本竹类的系统发育，结果支持温带木本竹类的单系。基于叶绿体片段构建的系统树包括10个主要支系，各支系之间的关系未得到解决，这些支系在亚族和属的等级上都与经典分类有明显冲突，有些支系中的亚支呈现出与地理分布的相关性。基于GBSSI基因构建的系统树中，有5个支系与叶绿体系统树一致，而其他支系均与叶绿体系统树有不一致之处。叶绿体系统树与核基因系统树之间的冲突，可能是由杂交、渐渗、谱系分选造成的网状进化引起的。结合分子系统学、地理分布和形态学特征，推测温带木本竹类是适应性辐射形成的类群，同时对10个可能的杂交种进行了分析。对温带木本竹类代表类群进行了叶表皮微形态观察，可以分为9种类型，为分类学及杂交种的鉴定提供了微形态学证据。此外，根据野外考察和标本馆工作，对几个明显的分类学问题进行了订正。

Abstract： The temperate woody bamboos are a morphologically diverse group with a complicated taxonomy. The Arundinaria group has an East Asia-North America disjunct distribution, which is one of those with complex taxonomy in the temperate woody bamboos. In this study, the phylogeny of the temperate woody bamboos was reconstructed based on eight non-coding regions of the chloroplast genome and nuclear gene GBSSI using large sample set (124 species in 24 genera) with an emphasis on the Arundinaria group. The monophyly of the temperate woody bamboos was resolved in all phylogenies. Ten major lineages were obtained in the chloroplast phylogeny with unresolved relationships among them; the recovered phylogeny is strongly incongruent with the classifications based on morphology at both subtribal and generic ranks; some subclades that are related to the geographic distribution were obtained in those lineages. Five lineages in the GBSSI gene phylogeny were recovered as the same in the chloroplast phylogeny, and the other lineages were incongruent with chloroplast phylogeny in some ways. The reticulate evolution caused by hybridization, introgression and lineage sorting may be an explanation for the molecular phylogenetic incongruence. Based on the facts of diverse morphology, broad distribution and molecular phylogeny, we inferred that the major clades and species within most of the clades of the temperate woody bamboos were originated during several rapid adaptive radiations. Ten putative hybrids were discussed based on molecular phylogenies, morphology and distribution. The micromorphology of the leaf epidermis under SEM (scanning electron microscope) was observed and divided into nine types; the micromorphology can provide some evidence for the bamboo taxonomy and inference of putative hybrids. Additionally, taxonomic revisions were presented for some species based on field observation and herbarium work.