甘肃不同地理种群桃蚜的遗传相似性

Genetic Similarity of Myzus persicae from Different Geographical Populations in Gansu Province

【目的】探讨甘肃不同地理种群桃蚜Myzus persicae的遗传相似性和遗传差异,遗传距离与地理距离、海拔之间的关系,以期得到桃蚜种群遗传分化和迁飞的分子证据。【方法】利用7对SSR引物对13个桃蚜地理种群进行遗传相似性和聚类分析。【结果】7对SSR引物共检测到43个多态性位点,多态性条带百分率PPB为95.56%。13个桃蚜地理种群观测等位基因数Na为1.3333,有效等位基因数Ne为1.2293,Nei′s基因多样性指数为0.1311,Shannon信息指数I为0.1898,多态位点百分率P为33.33%。临洮、临夏、岷县、兰州种群的遗传多样性较高,天水、酒泉、漳县种群相对较低。种群聚类分析结果显示,桃蚜分为河西和河东两大类群,AMOVA分析结果表明,类群间遗传变异占总变异的1.76%,种群间变异占17.21%,种群内占81.03%。Mentel检测表明,遗传分化与地理距离、海拔无显著相关性。【结论】甘肃省桃蚜种群具有非常丰富的遗传多样性,遗传变异主要来自种群内部,种群间的基因交流较少,容易发生遗传漂变;陕北、陇东、陇南是陇中桃蚜虫源地,应加强对上述地区桃蚜的监测和治理。

【Objective】 The genetic similarity and genetic difference of Myzus persicae among geo-populations from different regions in Gansu province were detected to analyze the relationship between genetic distance and geographical distance and elevations. The objective was to acquire molecular evidences of the genetic differentiation and migration of peach aphids. 【Method】 The genetic similarity and clustering of 13 geo-populations of Myzus persicae were analyzed using 7 SSR primers. 【Result】 A total of 43 polymorphic loci were detected with 7 SSR primers, the percentage of polymorphic bands （PPB） was 95.56%. For these geo-populations, the average number of alleles （Na） per locus was 1.3333, and the effective number of alleles （Ne） was 1.2293. The Nei′s gene diversity （H） and Shannon information index （I） were 0.1311 and 0.1898, the percentage in polymorphic loci was 33.33%. The genetic diversity of Lintao, Linxia, Minxian and Lanzhou populations was higher, and the diversity of Tianshui, Jiuquan and Zhangxian was lower compared with others. The cluster analysis showed that the populations could be divided into Hexi and Hedong groups. Analysis of AMOVA showed that there were about 1.76% of the total variations between two groups, 17.21% of the total variations among populations, 81.03% presented within populations. Mantel test revealed that there were no significant correlation between genetic distance and geographical distance and elevations. 【Conclusion】 Gansu populations of Myzus persicae have relatively high levels of genetic diversity. The genetic differentiation was mainly from inner populations and gene is seldom exchanged among populations, so genetic drift occurres easily. North of Shanxi, East of Gansu and South of Gansu are the source regions of Myzus persicae in the middle part of Gansu.