【作者】 王晓琴；

【导师】 成仿云； 张德强；

【作者基本信息】 北京林业大学 ， 园林植物与观赏园艺， 2009， 博士

【摘要】 滇牡丹(Paeonia delavayi)是我国西南地区特有野生植物,遗传变异十分丰富,其紫色花和黄色花植株已成为欧美园林绿化中常见的观赏植物,并在欧美牡丹品种群的建成中发挥了重要的作用。滇牡丹作为国家二级保护植物,在植物红皮书中被列为渐危种,然而其珍贵的基因资源在我国尚未得到有效保护和开发利用,分类学及遗传多样性研究尚未系统揭示种内主要变异类型,对其丰富变异的起源未见任何研究报道,保护开发工作缺乏基础资料和理论指导。香格里拉位于滇牡丹分布区中心地带,本研究在其境内开展野外调查,并选取生态条件较为一致的野生群体,首次从表型和分子水平上系统开展遗传多样性研究,旨在揭示滇牡丹遗传变异及可能成因,并试图探索其种内丰富变异的起源,为滇牡丹保护和开发工作提供理论基础,主要研究结果如下:1.香格里拉气候、生态条件较为复杂,滇牡丹在其境内分布广泛;境内表型变异未见受海拔、气候等环境因素影响;滇牡丹花期5-6月,果期8-10月,无性繁殖方式多样。2.香格里拉滇牡丹在株高、一年生枝长、一年生枝颜色、叶裂片数、叶裂片宽、叶裂片长、叶柄长、叶长、叶宽、叶色、花瓣是否具斑、花色、花丝颜色、花药颜色、柱头颜色、心皮颜色、花盘颜色、花瓣数、花径、单枝开花数、花梗长、心皮数、萼片数、苞片数等24个性状均存在变异。相关分析表明19个性状与株高、17个性状与花色显著(P＜0.05)或极显著相关(P＜0.001),据此野生群体划分为10个花色组及组内低、中、高共25个类型。聚类分析表明绿色、黄绿色、黄色、橙色、复色和红色、紫红色、紫色、墨紫色、粉色等花色组分别聚为两组,复色组的高型与墨紫色组中型关系较近,不同花色组的低型聚在一起。3.数据分析表明滇牡丹种内株高、叶长及叶宽、小叶裂片数及裂片长与宽、花瓣数、花径、心皮数等数量性状变异连续。主成分分析表明紫色花植株和黄色花植株存在明显分化;紫色花植株、黄色花低矮植株及其他植株三者株高、花瓣数、花径、心皮数、萼片和苞片数、叶宽差异极显著,叶裂片数、叶裂片长差异显著。判别分析证实以上三个类群划分正确率达89.8%。4.采用ISSR标记技术对滇牡丹遗传多样性进行了研究,结果表明多态性条带比率(PPB)为80.60%,Nei’s基因多样性指数(H)为0.3506,Shannon’s多态性信息指数(I)为0.5032。判别分析结果表明10个花色组类群划分正确率达85.6%,组间基因分化系数Gst为0.2567。花色组间基因流Nm为1.4477,橙色组、复色组、红色组等中间花色组与黄色组及紫色组、墨紫色组之间均存在较高水平的基因交流。聚类分析表明橙色组、复色组与黄色组亲缘关系较近,红色组与墨紫色组亲缘关系较近,紫红色组与紫色组亲缘关系较近。类型间的聚类结果较为复杂,其中黄色组、橙色组、复色组的低矮类型聚在一起。综合以上研究,通过野外调查及从表型和分子水平上揭示香格里拉滇牡丹野生群体遗传多样性,结果表明(1)滇牡丹生态环境适应性较强,中间花色植株常伴随紫色花、黄色花植株共同分布:(2)香格里拉野生群体内存在10个花色组及25个类型,均具保护和开发价值;(3)不同花色组及类型间存在基因交流,亲缘关系主要与花色、株高差异程度有关,对于杂交育种工作具有指导意义。本研究(1)支持将原分类处理中的所有类群归为一个种,即滇牡丹P.delavayi;(2)证实滇牡丹种下除原变种P.delavayivar.delavayi外,存在黄牡丹P.delavayi var.lutea、矮黄牡丹P.delavayivat.humilis等类群;(3)揭示滇牡丹种内连续变异可能起源于种下原变种及变种间的天然杂交。更多还原

【Abstract】 Paeonia delavayi,native to Southwest of China,has rich phenotypic variation.The plants with purple and yellow flowers were introduced into France in1884 and have been used widely in European and American gardens.Moreover,they have played great roles in Moutan cultivars breeding in France and the U.S.A.As a vulnerable plant,P.delavayi hasn’t been protected effectively or developed in China.The taxonomy and genetic diversity research about it has never revealed main types of variation yet and the origin of variation has been a mystery.To supply fundamental data and theoretical direction of its protection and development,on basis of system investigation,the phenotypic variation and ISSR markers diversity have been studied on a population under the same ecological conditions.The results are as follows:There are complicated climatic and ecological conditions in Shangfi-la and it is typical of P.delavayi distribution zones.P.delavayi is widely distributed in Shangri-la.There was variation on height,length of current season stem,segment number,segment width,segment length,leaf length,leaf width,leafstalk length,petal number,flower size,flower number on one branch,pedicle length,carpel number,sepal numberand bract number of P. delavayi.Other thaits are significantly relative to height and flower color.Ten groups were listed as green,kelly,yellow,orange,secondary,red,magenta,purple,dark purple,pink flower groups in the population and low,medium and high types existed in a group except green flower group because of its limited number.Moreover,there were no low type in pueple and dark purple flower group.Through cluster analysis on basis of 24 traits,the ten groups were classified into two clusters.The five groups from green to secondary color were in ClusterⅠwhile the left five groups were in ClusterⅡ.The short types of all groups gathered in one cluster.P.delavayi showed continuous variation on height,leaf length,leaf width,segment number,segment width,segment length,petal number,flower size and carpel number and it supported that Hong recognized only one species,P.delavayi.At the same time,the three species in the former taxonomic treatment were discussed further.The result showed segment width of leaf was susceptible to environmental factors especially light and P potanini wasn’t able to be recognized on grounds of it.The plants with purple flowers,the short plants with yellow flowers and the other plants with yellow flowers showed significant difference on height,leaf width,segment number,segment length,petal number,flower size and carpel number of sepal bract.The paper identified that P.delavayi var.lutea and P.delavayi var.humilis as infraspecific taxa.ISSR markers revealed a total of 134 bands were amplified from 180 individuals of P.delavayi.A relatively high level of infraspeeific genetic diversity was revealed: PPB=80.6%,H=0.3506 and I=0.5034.The discriminant analysis showed that the classification accuracy among ten groups was 85.6%.The gene differation Gst was 0.2567 while the gene flow Nm was 1.4477.Gene exchange existed widely among groups,especially among thee groups with in-between color flowers.High gene flow existed between them and plants with yellow flowers or with purple flowers.Moreover,the cluster analysis revealed the ten groups gathered.The green,the kelly,the yellow flower groups had close relationship while the red and the dark purple flower groups comes closer and the margeta and the purple flower groups are closer.From the research above,it was summarized(1) P.delavayi population in Shangri-la had great genetic polymorphism;(2)flower color and height were leading factors in genetic diversity and there were ten flower color groups with 25 height types in them with great ornamental value;(3)gene exchange existed widely among groups and types and their relationship dependeded on difference of flower color and height,which helps guide cross-breeding.The paper(1) supports that Hong recognized only one species,P.delavayi.(2) identifies that P.delavayi var.lutea and P.delavayi var.humilis as infraspecific taxa.(3)reveals infraspecific variation of P.delavayi may originate from spontaneous hybridization between the infraspecific variaties.更多还原