摘要榧属Torreya植物为国家保护植物，浙江现知有3种、1变种。通过对浙江榧属植物3种、1变种的20个个体，利用2个叶绿体基因trnL-trnF和trnM-trnS的扩增、测序和序列分析，探讨了浙江榧属植物的系统发育关系，结果如下：（1）在本实验中，种子具皱胚乳的巴山榧、九龙山榧和长叶榧和胚乳微皱的榧属均聚在第1枝，这与Li等（2001）基于ITS序列对于榧属植物系统发育关系研究的结果是一致的。这说明种子中胚乳是否皱缩不能作为榧属下分组的依据。（2）九龙山榧的分类地位依然模糊，既不能证明其杂交的可能，也不能支持其作为种级独立于榧树和长叶榧，其分类问题依然悬而未决。（3）选用变异较大、通用性较好的trnL-trnF和trnfM-trnS，结果显示变异位点/信息位点极少，不足5%，因此可能导致系统发育关系树分辨率低，形态学上差异明显的种间区分度不高。其解决办法是更广泛的取样，应用核基因、叶绿体基因和线粒体基因联合分析，或许是解决目前榧属系统发育关系存在问题的途径之一。88006

Abstract Torreya belongs to national conservative plants, of which three species and one variety have been found in Zhejiang。 By performing amplification, sequencing and sequence analysis to two genes -- trnL-trnF and trnM-trnS in chloroplasts of twenty inpiduals from the three species and one variety found in Zhejiang, this study explores the phylogenetic relationships of the Torreyas in Zhejiang。 The results are as follows: (1) In this experiment, the Torreya jiulongshanensis, Torreya fargesii and Torreya jackii which are all with wrinkled albumenin and the Torreya with slightly wrinkled albumenin all gathered in the first branch。 It is coincident with the results of Liu et al。’s study (2001) based on the r DNA ITS sequences。 So the degree of wrinkle can’t be regarded as the rule of grouping the torrreya。 (2) The taxonomic status of Torreya jiulongshanensis is still fuzzy because of the indefensibility in the possibility of hybridization and the lack of evidence of being a particular species from Torreya grandis and Torreya jackii。 So its taxonomy hangs in doubt。 (3) This study chooses trnL-trnF and trnfM-trnS which show great variability and universality and few variable sites/informative sites are manifested in the result-- less than 5 %。 It may result in low resolution in phylogenetic relation tree and ambiguous differentiation among species which are quite different morphologicaly。 The solution is increasing the samples then conducting a joint analysis of the nuclear genes chloroplast genes and mitochondrial genes which may be one of the methods of solving the problem in phylogenetic relationships of the Torreyas。源-于,优W尔Y论L文.网wwW.youeRw.com 原文+QQ75201,8766

毕业论文关键词：榧属植物，叶绿体基因，系统发育关系

Keyword: Torreya, chloroplast genes, phylogenetic relationships

目录 3

1 引  言 4

2 材料与方法 4

2。1 实验材料 4

2。2 实验方法 5

2。2。1 基因组DNA的提取 5

2。2。2 PCR扩增 5

2。2。3序列编辑和系统发育关系分析 5

3 结果 6

3。1 DNA提取和PCR扩增 6

3。2 聚类分析 7

3。3 系统发育关系树 8From~优E尔L论E文W网wWw.YoUeRw.com 加QQ7520.18766

4 结语 9

4。1 从浙江的榧属植物系统发育看榧属的系统学