【作者】 何淼；

【导师】 卓丽环；

【作者基本信息】 东北林业大学 ， 园林植物与观赏园艺， 2007， 博士

【摘要】 本文选取来自于核基因组和叶绿体的三个DNA序列片段，对东北地区丁香属进行系统发育的重建，主要探讨了东北地区丁香属下系统的划分和属下分类群间的亲缘关系。对东北地区丁香属植物进行大量的分子系统学研究的同时，还对其形态性状进行了分支分析，探讨了丁香属的起源和演化问题。主要内容包括：1、基于形态性状的分支分析通过对东北地区应用的丁香属植物的形态学性状的观察，采用分支系统学的方法，对其进行分支分析，利用PHYLIP和MEGA软件，分别应用最大简约法和UPGMA法对其进行系统发育分析，结果表明：东北地区丁香属植物分为4个分支，分别属于Rehder(1928)分类方法组1和组2中的不同的系，从一个侧面说明基于经典分类划分的系是比较自然的，而我们研究后认为去除组的划分，将丁香属分为五系，即顶生花序系(Ser．Villosae)、欧丁香系(Ser．Syringa)、巧玲花系(Ser．Pubescentes)、羽叶丁香系(Ser．Pinnatifoliae)和短花冠系(Ser．Ligustrina)。2、叶绿体TrnL-trnF间区序列及系统发育扩增并分析了东北地区丁香属11种植物及外类群的trnL-trnF基因间隔区序列，其长度变异范围为362-374bp，排序后的长度为382bp，其中35个变异位点，所占比例为9.16％，序列的G+C平均含量为37.2％，说明trnL-trnF序列的A+T含量较高。对东北地区丁香属植物基于cpDNA的TrnL-trnF间区序列应用MP法、ML法、UPGMA法和NJ法构建系统发育树，结果表明：在东北地区丁香属植物内稳定的分成四个类群，洋丁香、朝鲜丁香、什锦丁香和紫丁香构成一个类群，即欧丁香系(Ser．Syringa)，关东丁香、小叶丁香和毛丁香构成一个类群，即巧玲花系(Ser．Pubescentes)，红丁香和辽东丁香构成一个类群，即顶生花序系(Ser．Villosae)，北京丁香和暴马丁香构成一个类群，即短花冠管组(Sect．Ligustrina)。不同方法分析的各类群之间的关系不同，构建的发育树存在一定的差异。3、nrDNA ITS序列的分析及系统发育东北地区丁香属11种植物及外类群的ITS序列4种核苷酸量平均为A=30.5％，C=21.5％，G=32.0％，T=16.0％。将所获得的ITS序列排序后，比较形成了一个含623个位点的矩阵，其中544个不变位点，79个变异位点，所占比例为12.7％，ITS序列的G+C含量较高，都在50％以上，平均含量为54.8％。东北地区丁香属内G+C含量相差不大，最低的是洋丁香，为53.86％，最高的为北京丁香为55.86％，而东北连翘的G+C含量为54.9％。对东北地区丁香属植物基于ITS区序列构建的系统发育树分析后发现，在东北地区丁香属植物内稳定的分成四个类群，与TrnL-trnF间区研究结果相同，但基于不同的系统分析方法构建的系统发育树在属下各分类群的之间的亲缘关系的确定上有一定的差异。4、nrDNA ETS序列的分析及系统发育东北地区丁香属11种植物ETS序列4种核苷酸量平均为A=19.8％，C=24.5％，G=24.6％，T=31.2％。将所获得的ETS序列排序后，比较形成了一个含380个位点的矩阵，其中323个不变位点，57个变异位点，所占比例为15％，东北地区丁香属植物ETS序列的G+C含量在48％-50％以下，平均含量为48.99％。东北地区丁香属内G+C含量相差不大，最低的是毛丁香，为48.1％，最高的为朝鲜丁香为50.0％，而辽东水腊的G+C含量为48.94％。对东北地区丁香属植物基于ETS区序列构建的系统发育树分析后发现，在东北地区丁香属植物内稳定的分成四个类群，与TrnL-trnF间区、ITS序列的研究结果相同，但应用系统分析方法所构建的系统发育树在属下各分类群的之间的亲缘关系的确定上与TrnL-trnF间区、ITS序列的研究结果有一定的差异。综合文献资料和本研究结果，我们认为：1、cpDNA TrnL-trnF间区序列、nrDNA ITS和ETS序列在研究丁香属下分类和丁香属植物的系统进化方面可以提供一定的变异位点，在种间的系统发育重建研究中可以提供较丰富的信息，具有一定的研究价值。2、丁香属植物的经典分类划分的系是比较自然的，而我们研究后认为去除组的划分，将丁香属分为五系，即顶生花序系(Ser．Villosae)、欧丁香系(Ser．Syringa)、巧玲花系(Ser．Pubescentes)、羽叶丁香系(Ser．Pinnatifoliae)和短花冠系(Ser．Ligustrina)。3、基于不同的序列和不同的系统分析方法构建的系统发育树在属下基部分支的确定上有一定的差异，但按照多数原则，我们推断：欧丁香系(Ser．Syringa)为基部分支，巧玲花系(Ser．Pubescentes)是进化过程中的一个中间类群，项生花系(Ser．Villosae)可能是一个较原始的类群。更多还原

【Abstract】 The phylogenetic relationships of Syringa in Northeastern China were investigated by means of molecular systimatics, which was based on three DNA sequences from genomes,including chloroplast DNA trnL-trnF, nrlTS and nrETS gene.The present study includes classification within the Genus Syringa and relationships of taxa groups.In addition, a cladistic analysis based on the morphology of Syringa was carried on. The results were summarized as follows,1. Cladistic analysis based on the morphologic charactersA cladistic analysis of the genus Syringa from the Northeastern China was carried out through surveying on the morphologic characters and using MP and UPGMA methods by MEGA 3.1 and PHYLIP 3.65. The results showed, 11species of Syringa were divided into four clades and belonged to relevant Series of SectⅠ. Ligustrina and SectⅡ. Syringa classified by Rehder (1928). So it is well supported to Rehder’s infrageneric system. Through analysis we considered that the genus Syringa would be divided into five series, Ser. Villosae, Ser. Syringa, Ser. Pubescentes, Ser. Pinnatifoliae and Ser. Ligustrina.2. Studied on the cpDNA TrnL-trnF Intergenic Spacer Sequence in the Genus Syringa of Northeastern ChinaThe cpDNA TrnL-trnF intergenic spacer sequence in the genus Syringa were amplified and sequenced successfully, the size of which are about 362-374bp.After alignment the size of sequences are 382bp,including 35 mutations. The contents of G+C are37.2%, which showed the trnL-trnF sequences were AT-rich fragment. Based on TrnL-trnF Intergenic Spacer Sequence, the phylogenetic reconstruction were performed using the parsimonious anlysis (MP), the maximum likelihood (ML),UPGMA and the neighbor-joining(NJ)methods, repectively.The results show that: 11species of Syringa were divided into four groups, Syringa chinensis, S. dilatata, S. oblata and S. vugaris were one group ; S. pubescens ,S. velutina and S. microphylla were one group ; S. villosa and S. wolfii one group; S. pekinensis and S. reticulata var. mandshurica one group. The relationships among groups were different based on different methods, and the phylogenetic trees were different.3. Studied on the nrDNA ITS Sequence in the Genus Syringa of Northeastern ChinaThe average content of A is 30.5%, C 21.5%, G32.0%,T16.0% in 11 species of Syringa and outgroup species. After alignment the size of sequences are 623bp, including 79 mutations, and the rate is 12.7%.The contents of G+C are higher than 50%, and the average is 54.8%. The difference of the contents of G+C is not significant, the smallest one is 53.86%( S. vugaris), the biggest one is 55.86%( S. pekinensis) , and the contents of G+C of Forsythia mandshurica is 54.9%.Based on the ITS sequences the phylogenetic reconstruction showed the similar results with the cpDNA TrnL-trnF Intergenic Spacer Sequence,but based on the different methods the relationships among series below genus were different. 4. Studied on the nrDNA ETS Sequence in the Genus Syringa of Northeastern ChinaThe average content of A is 19.8%,C 24.5%, G24.6%,T31.2% in 11 species of Syringa and outgroup species. After alignment the size of sequences are 380bp, including 57 mutations, and the rate is 15%.The contents of G+C are from 48% to 50%, and the average is 48.99%. The difference of the contents of G+C is not significant, the smallest one is 48.1%(S. pubescen), the biggest one is 50% ( S. dilatata), and the contents of G+C of Ligustrum obtusifolium is 48.94%. Based on the ETS sequences the phylogenetic reconstruction showed the similar results with the cpDNA TrnL-trnF Intergenic Spacer Sequences and ITS sequences, but the relationships among series below genus were different with the results of the cpDNA TrnL-trnF Intergenic Spacer Sequences and ITS sequences.Based on the former literatures and present studies, the main conclusions are presented as follows:1. The cpDNA TrnL-trnF Intergenic Spacer Sequences ,nrDNA ITS and ETS sequences have some mutations among the Genus Syringa and it is feasible using these three sequences to discuss the phylogeny relationship in Syringa.2. Syringa should be divided into five series, including Ser. Villtosae,Ser. Syringa,Ser. Pubescentes ,Ser. Pinnatifoliae and Ser. Ligustrina.3. Based on the different sequences and the different analysical methods The relationships among series were different, but we con conclude that Ser. Syringa is the base clade, Ser. Pubescentes is the mid-type ,and the Ser. Villosae may be one original type.更多还原