新疆野苹果群体遗传结构和遗传多样性的SRAP分析

 采用SRAP标记，对中国新疆野苹果4个种下居群的群体遗传结构和遗传多样性进行了研究。结果表明：10对SRAP引物总共扩增了209条带，其中206条是多态性带（98.56%）。巩留群体、新源群体、霍城群体和裕民群体分别扩增了180、169、178和165条多态性带，巩留群体的随机交配杂合度（hs = 0.3037 ± 0.0058）最高，其次为霍城群体。UPGMA聚类分析和群体间遗传分化系数显示，巩留群体和新源群体之间，以及霍城群体和裕民群体之间，遗传关系最近，群体间遗传变异最低。新疆野苹果群体内遗传变异高于群体间，占总变异的87.9%，主坐标轴分析显示4个群体是相对独立，其中巩留群体和新源群体，霍城群体和裕民群体之间，有较高的基因交流。所有参数分析表明，巩留群体遗传多样性最丰富，故在制定新疆野苹果原地和异地种质保护计划时应优先考虑巩留群体。

SRAP Markers for Population Genetic Structure and Genetic Diversity in Malus sieversii from Xinjiang,China

The genetic diversity and genetic structure of four Malus sieversii eco-geographical populations from Xinjiang, China were studied　by SRAP marker. The results showed that 209 bands were amplified totally by ten pair SRAP primers, of which 206 bands (98.56%) were polymorphic in the species level and the number of polymorphic bands (A) was 180, 169, 178 and 165, respectively, at Gongliu, Xinyuan, Huocheng, and Yumin populations. The average panmictic heterozygosity (hs = 0.3037 ± 0.0058) in the Gongliu population was the highest, followed by the Huocheng population. UPGMA cluster analysis and genetic differentiation among populations showed that there had closer genetic relationship between Gongliu and Xinyuan populations and between Huocheng and Yumin populations and lower genetic variation between the populations. For M. sieversii, genetic variation within population, which was higher than between the populations, accounted for 87.9% of total variation. The principal coordinates analysis showed that the four populations were relatively independent populations, in which between the Gongliu and Xinyuan populations and between Huocheng and Yumin populations had higher gene exchange. On the basis of the study of population genetic structure and genetic diversity, Gongliu population should be given a high priority consideration in Malus sieversii germplasm conservation both in situ and ex situ.