【作者】 赵杨；

【导师】 陈晓阳；

【作者基本信息】 北京林业大学 ， 林木遗传育种， 2006， 博士

【摘要】 本研究选取二色胡枝子分布区内14个种源的161个样本为试材,通过形态学性状调查、种子储藏蛋白测定和ISSR、AFLP两种分子标记,从三个层次对二色胡枝子遗传变异规律进行研究。同时,采用ISSR分子标记技术和ITS序列分析,研究胡枝子属主要种之间的亲缘关系。研究结果如下:(1)通过对19个性状分析表明,除地径、分枝数、旗瓣长和荚果长外,其余15个性状种源间差异均达到显著水平或者极显著水平,二色胡枝子性状变异主要存在于种源内。19个形态学性状中,变异系数平均值最大的是单株产种量,其次是分枝数,变异最小的是荚果的形态性状。主成分分析分析结果显示,花部性状、株高、地径、节间长度、叶宽等性状是造成二色胡枝子形态学性状变异的主要因素。聚类分析结果表明14个二色胡枝子种源可以分为3类。(2)对14个种源147个个体单粒种子盐溶蛋白进行了电泳检测,共检测到28个蛋白单体,其中多态性单体23个,多态百分率为82.14%,各种源内多态百分率平均为33%。各种源间的遗传分化系数Gst为0.4669。种源内变异是二色胡枝子遗传多样性的主要来源。聚类分析结果将14个二色胡枝子种源分为三类,种源间地理距离和遗传距离相关性不显著。(3)建立和优化了二色胡枝子ISSR反应体系。筛选出16条ISSR引物用于遗传多样性研究,共扩增出ISSR标记229个,多态性标记百分率为91%,二色胡枝子无论在种水平(P=91%,H=0.392,I=0.576)还是在种源水平((P=68.2%,H=0.227,I=0.392)都表现出较高的遗传多样性。各遗传多样性参数与地理因子(经、纬度)、气候因子(年均温,年降水)间均无显著相关性。遗传多样性主要存在于种源内,占75.66%左右。种源间有一定的基因流(Nm=1.0522)。基于遗传距离的聚类结果将14个种源分为三大类。(4)利用AFLP技术对胡枝子遗传多样性进行了分析,5对引物共检测到AFLP标记253个,多态带百分率(P)为96.8%,二色胡枝子种群的平均位点等位基因数(A)为1.968,平均有效等位基因数(Ae)为1.643,Nei’s基因多样性指数(H)更多还原

【Abstract】 Fourteen provenances of Lespedeza bicolor in China, about 161 samples, were selected and investigated in this study. Genetic diversities of Lespedeza bicolor were evaluated through phenotype study, seed saved protein SDS-PAGE and two molecular markers (ISSR, AFLP). Additionally, the phylogenetic relationship among some main species of Lepedeza Michx was explored by means of ISSR markers and data of ITS sequences. The results and conclusions obtained are as follows.1. The variation of phenotypic characteristics was complicated. The variation within provenances is higher than that among provenances in this study. The average variation coefficient of the SY(seed yield per plant), among the nineteen morphological traits, is the highest and followed by the BN (branch number). According to the PCA, the traits about bloom, plant height, ground diameter, internode length and leaf width were the main traits for the phenotypic variations analysis. Based on cluster analysis, fourteen provenances of Lespedeza bicolor were divided into three groups by phenotypic traits.2. SSP inheritance and variation were studied by using SDS-PAGE among 147 samples from fourteen provenances of Lespedeza bicolor. 28 loci were tested totally, in which 23 loci were polymorphic. The polymorphic rate was 82.14%. The average coefficient of gene differentiation (Gst) was 0.4669 and approximate 53.3% of the SSP variation occurred within provenances. According to the UPGMA cluster analysis based on the genetic distance, fourteen provenances of Lespedeza bicolor were divided into three更多还原