【作者】 仲轶；

【导师】 王玲；

【作者基本信息】 东北林业大学 ， 园林植物与观赏园艺， 2010， 硕士

【摘要】 本研究为国家自然科学基金项目部分研究内容。鸢尾属(Iris·L.)是单子叶植物中鸢尾科中最大的属,全世界记载有300余种,中国约有60种,为世界分布中心。该属植物观赏价值颇高,野生的鸢尾属植物不但生命力顽强,抗逆性强,而且叶片绿色期长,是很好的观叶植物,有广阔的推广应用前景。但是存在于引种和鉴定等方面上的困难,导致我国对该属系统分类还存在许多争议。基于上述原因,本实验在前人的研究基础上,延续分类学研究朝着系统植物学和进化植物学两个发展方向,从目前比较认可的Mathew和Rodionenko两位学者对鸢尾属植物的系统分类关系上入手,对中国鸢尾属进行了较为系统的分子进化方面的深入研究。随着研究方法与手段的不断创新,系统进化关系的研究开始转向以研究植物类群微观系统特点上,使以往经典分类学在理论上和方法上经历了一场变革。因此真正系统地了解鸢尾属植物系统发育进化关系,将为其今后育种、繁殖和园林广泛应用提供理论指导与技术支持,对我国的城市绿化建设也将发挥巨大作用。鉴于此目的,本论文以全国野生鸢尾属中的45个分类群典型植物共80份样品为研究对象(中国约产60种鸢尾,实验种类占其75%以上,代表了其中的6个亚属和除了Sec. Lophiris的所有亚属下的组)。分析选取了四个叶绿体基因片段(matK, trnL-trnF, rbcL, psbA-trnH)和一个核基因片段(CHS)以及部分种已知的染色体数目。以基因组序列为主结合部分细胞染色体数目进行研究,给出Iris属植物属下亚属和组的分类学修订意见。研究结果如下：(1)四套叶绿体基因片段的和CHS核基因片段联合分析很大程度的提供了鸢尾属的系统发育关系上的证据；对45个分类群的序列进行测定,结果表明可以将我国属内植物系统以Subgenera Iris、Subgenera Limniris为主划分为三个大类群。(2)从拓扑结构得出Subgenera Crossiris不支持作为一个单系,但仍有保留的必要,系统位置值得继续探讨。(3)从染色体数目和基因进化关系得出,Subgenera Xyridon和Subgenera Pardanthopsis两个亚属主要种系统位置有很大变化,琴瓣鸢尾种不应划分在琴瓣鸢尾属中,而作为我国特有种中甸鸢尾应从野鸢尾亚属中调整到尼泊尔鸢尾亚属当中。(4)比较了两个主要属下分类系统,进一步建立和修订了中国鸢尾属的分类系统。并在保留Subgenera Crossiris的基础上,将最为复杂的亚属Subgenera Limniris种类各个组下系按Mathew系统提升到组来讨论。(5)对多个目前有争议的分类群进行了讨论和修订,探讨了它们的系统位置和归属问题,并利用母系遗传的叶绿体基因和双亲遗传的单拷贝基因分析出鸢尾属的进化趋势。更多还原

【Abstract】 The Genus Iris L. is the largest and most evolutional genus in Iridaceae of monocotyledons. There are more than 300 species around the world and 60 species in China. It’s distribution centers in the world. The wild plants of the genus Iris have high ornamental value. Both life force and resistance are strong at the same time they keep green for long time. And are very good view fallacious plant, having broad application prospect. But there were difficulties in the introduction and identification, leading to our taxonomy of the genus still exist many disputes. In view of the above mentioned reasons, on the basis of the works of our predecessors, we continue to study on a system of botanical classification and evolutionary botany two development directions, more recognition from the current two scholars Mathew and Rodionenko systematic of the genus Iris relations, trying to make a thorough and systematic study of molecular evolution on the Chinese Iris in China.With innovation of the research methods and means, the phylogenetic study of plant groups began to shift to micro-system characteristics, so that the classical taxonomy of the past in theory and methods experienced a change. Finding out genus evolved system of Iris will provide theoretic instruct and technical support for breeding, propagation as well as application in garden. For this purpose, we choose wild Iris taxa in 45 of 80 samples of typical plants for the study (China produced about 60 Iris,75% of its experimental species, represents one of six sub-genus and in addition to Sec. Lophiris under all the group). Analysis of four chloroplast genes (matK, trnL-trnF, rbcL and psbA-trnH) and one nuclear gene fragments (CHS) and known chromosome number of some species were selected. Combined with the main part of the genome sequence of chromosome number of studies, we give its subgenus Iris species and taxonomic groups for revision. The results as follows:(1) The four plastid gene segments and CHS nuclear genes joint analysis of fragments largely were seted to provide the phylogeny evidence of the genus Iris; the results of the 45 taxa sequenced show that we can divided into three major groups within the plant system by Subgenera Iris, Subgenera Limniris mainly.(2) The topological structure show that Subgenera Crossiris does not support as a single department, but there is still necessary to retain the systematic position and worth pursuing.(3) The chromosome number and genes of the evolutionary relationships obtaining show that the relationship of Subgenera Xyridon and Subgenera Pardanthopsis has very big change in main position. I.halophila should not be divided into Subgenera Xyridon, and as endemic to China I.subdichotom should adjust to Subgenera Nepalensis.(4) Comparing the two major subordinate classification systems, further establish and revise the classification system of Iris from China. And keep Subgenera Crossiris, the most complex types of the various Subgenera Limniris species under different groups upgrading to the group by discussion according to Mathew system of group.(5) The discussion and amendments of many contentious taxes were carried based on the experimental results; their classificatory position and belonging were discussed.更多还原