中文摘要：

以40个核桃（Juglans regia）地理群体及5个外类群植物为材料,利用苯丙氨酸解氨酶基因片段JRD5680序列对265个个体研究了我国不同地区核桃的群体遗传多样性、群体遗传结构以及单倍型地理分布。结果表明：核基因JRD5680序列长度为809 bp,其中G＋C碱基含量为46.2%,74个简约性信息位点。共30个单倍型,单倍型多样性变异小,表现出较低的遗传多样性（Hd=0.370,π=0.005 3）。核桃群体间有明显的谱系地理学结构（NST〉GST）,呈现地域性分布格局的特点。空间遗传结构分析表明,地理隔离距离与遗传距离之间也显示两者之间相关性显著（r=0.263 2;P=0.032 4＊）,不同地理分布核桃群体间存在着明显地理隔离效应。综合失配分析及中性检验的结果,可推断出近期历史上不同地区核桃没有发生群体扩张事件。遗传结构显示,核桃群体可分为两组（西南地区与其他地区）。AMOVA分析结果表明,核桃群体遗传变异主要存于群体之间（56.54%）,不同种之间的遗传分化水平较高（FST=0.885）。单倍型系统发育树中核桃与外类群物种均能形成单系分支,说明JRD5680序列在胡桃科中的具有较高的分子鉴别率。

英文摘要：

We studied the genetic diversity and population genetic structure of 265 individuals from different regions of China by using the roles of phenylalanine ammonia-lyase （PAL） nuclear gene JRD5680 DNA sequence of 40 common walnut（Juglans regia） and 5 out group plant species. The length of JRD5680 sequence was 809 bp, the content of G ＋ C was 46.2% with 74 information sites. A total of 30 haplotypes, haplotype diversity variation showed low genetic diversity （ Hd = 0. 370, π = 0. 005 3 ）. There is a clear geographical structure （NST 〉 GsT ） , which is a regional distribution pattern. The spatial genetic structure analysis showed that the correlation between geographical isolation and genetic distance was significant（ r =0. 263 2; P =0. 032 4 ＊ ）, and there was obvious geographical isolation effect among different geographic populations. The results of comprehensive mismatch analysis and neutral test can of the population expansion event. From the genetic groups（southwest and other regions）. By AMOVA, stored in the populations（56.54% ）, and the genetic be deduced from the recent history of the different regions structure, the walnut population can be divided into two the genetic variation among the populations was mainly differentiation among the populations was higher（ FST ： 0. 885 ）. The total of 5 species of Juglandaceae could be with high molecular identification radio in the members a single branch, and the JRD5680 sequence might be of the Juglandaceae.