绿色豌豆蚜不同地理种群的遗传多样性

豌豆蚜是我国苜蓿上危害最为严重的害虫之一。利用微卫星标记研究了我国绿色型豌豆蚜10个地理种群的遗传相似性、基因分化、遗传距离与地理距离和海拔之间的关系及其基因结构。选取15对引物扩增300个个体,共检测到41个多态性条带,多态性条带百分率(PPB)为100%。10个豌豆蚜地理种群观测等位基因数(Na)为1.592 7,有效等位基因数(Ne)为1.356 9,Nei’s基因多样性指数为0.206 6,Shannon-Wiener指数(I)为0.307 6。新疆维吾尔自治区、陕西省、河南省种群的遗传多样性较高,内蒙古自治区、山东省、青海省种群相对较低。然而,10个地理种群豌豆蚜(绿色型)的遗传分化较高(Gst=0.399 6)。种群聚类分析结果显示,全部豌豆蚜种群明显聚为两大类群,山东省、河南省种群为一大类群,其余为另一大类群。Mentel检测表明,遗传分化与地理距离、海拔无显著相关性。我国豌豆蚜种群具有非常丰富的遗传多样性,应加强豌豆蚜的监测和治理。

Genetic diversity of Acyrthosiphon pisum (green form) from differentgeographical populations

Acyrthosiphon pisum is one of the most devastating pests of alfalfa (Medicago sativa L.) in China. Using micro-satellite markers, we studied the genetic similarity and genetic differentiation among the pest geo-populations, and their relationships with genetic distance, geographical distance and elevation. We also evaluated genetic structure of ten A. pisum (green form) populations in different regions of China (Beijing City, Inner Mongolia Autonomous Region, Ningxia Hui Autonomous Region, Xinjiang Uygur Autonomous Region, and Gansu, Shaanxi, Shandong, Henan, Shanxi and Qinghai Provinces). A total of 41 (100%) polymorphic bands were detected using 15 pairs of SSR primers in 300 individuals across 10 populations. The number of observed alleles (N_a) per locus was 1.592 7 and that of effective alleles (N_e) was 1.356 9, with Nei's genetic diversity (H) of 0.206 6 and Shannon-Wiener diversity index (I) of 0.307 6. Populations from Xinjiang Uygur Autonomous Region, Shaanxi Province and Henan Province showed strong genetic diversity. In contrast, genetic diversity of Mongolia Autonomous Region, Shandong Province and Qinghai Province populations was much weak. Overall, there was a high genetic divergence among the 10 A. pisum populations (G_st = 0.399 6). Based on cluster analysis, the 10 A. pisum populations were divided into two distinct clusters. Cluster one (i) consisted of the populations from Shandong and Henan Provinces, while cluster two (ii) consisted of the populations from Beijing City, Inner Mongolia Autonomous Region, Ningxia Hui Autonomous Region, Xinjiang Uygur Autonomous Region, and Gansu, Shaanxi, Shanxi and Qinghai Provinces. Mantel-test analysis showed that genetic distance of A. pisum was no significantly correlated with geographic distance and elevation. As A. pisum (green form) population showed relatively high genetic diversity in China, there was the need to strengthen monitoring and management of pea aphids.