泥东风螺4个群体遗传多样性的AFLP分析

Genetic distance in four populations of Babylonia lutosa(Lamer) assessed by AFLP makers

利用AFLP分子标记方法对4个群体（福建连江野生、连江养殖、长乐养殖、广西野生）的泥东风螺进行遗传多样性分析。结果：用11对引物共扩增出908条有效片段，其中684条（75．33％）为多态性片段，224条片段（24．67％）为4个群体所共有；遗传多样性指数分析显示，4个群体的有效等位基因数、平均等位基因数、Shannon’s多样性指数和平均杂合度依次为1．5006、1．9740、0．4647、0．3034，Nei’s遗传距离为0．1284～0．1806，遗传相似系数为0．8348～0．8795，表明4个泥东风螺群体具有较为丰富的遗传多样性，且群体间具有较高的遗传相似性；分子方差分析（AMOVA）结果显示，4个群体中83．49％的变异来源于群体内，14．65％的变异来源于地区间，而群体间的遗传变异仅为1．86％，且4个群体间的遗传分化（GST）为0．1954，基因流（NM）为2．0586，说明群体间的基因交流水平较低；UPGMA聚类分析和主坐标（PCA）分析结果表明，长乐养殖群体和广西野生群体遗传距离最近，而连江野生群体与其他3个群体的遗传距离最远。

Genetic diversity of Lianjiang wild population （LJWN）, Lianjiang cultured population （LJYN）, Changle cultured population （CLYN）, Guangxi wild population （GXWN） of Babylonia lutosa （Lamer） was analyzed by amplified fragment length polymorphisms （AFLP）. For the assessment, total 908 bands were generated from four populations using 11 different primer combinations, 684 （75.33%） were polymorphic fragments of which 224 （24.67%） are shared by the four populations. Genetic diversity index analysis showed, the effective number of alleles, the average number of alleles, Shannon＇s diversity index and average heterozygosity were 1.500 6, 1.974 0, 0.464 7, 0.303 4, respectively; Nei＇s genetic distance and genetic similarity coefficient were ranged from 0.128 4 to 0.180 6 and 0.834 8 to 0.879 5, indicating relatively rich genetic diversity and high genetic similarity among the four populations of Babylonia lutosa （Lamer）.Results of analysis of molecular variance （AMOVA） and assignment test revealed 83.49% variation within population, 14.65% variation from region difference and 1.86% variation among the four populations. Genetic variance GST and NM were 0.195 4 and 2.058 6 among four population groups indicating that the gene exchange level is very low. The analysis results of UPGMA and PCA showed that the nearest genetic distance exists between CLYN population and GXWN population. Genetic distance between LJWN population and other 3 populations was the farthest.