Department of Entomology, College of Agronomy and Biotechnology, China Agricultural University, Yuanmingyuan West Rd. 2, Haidian District, Beijing 100193, China.
J Econ Entomol. 2011 Jun;104(3):1065-74. doi: 10.1603/ec10395.
The melon fruit fly, Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae), is widespread agricultural pest, and it is known to have the potential to establish invasive populations in various tropical and subtropical areas. Despite the economic risk associated with a putative stable presence of this fly, the population genetics of this pest have remained relatively unexplored in Asia, the main area for distribution of this pest. The goals for this study were to employ nuclear markers to examine geographic collections for population genetic structure and quantify the extent of gene flow within these Southeast Asian and Chinese populations. To achieve these goals, we used 12 polymorphic microsatellite markers. A low level of genetic diversity was found among collections from China and higher levels were seen in Southeast Asia collections. Three genetically distinct groups, Southeast Asia, southwest China, and southeast China, were recovered by Bayesian model-based clustering methods, the phylogenetic reconstruction and the principal coordinate analysis. The Mantel test clearly shows geographical distance contributed in the genetic structuring of B. cucurbitae's populations. No recent bottlenecks for any of the populations examined. The results of clustering, migration analyses, and Mantel test, strongly suggest that the regional structure observed may be due to geographical factors such as mountains, rivers, and islands. We found a high rate of migration in some sites from the southwest China region (cluster 1) and the southeast China region (cluster 2), suggesting that China-Guangdong-Guangzhou (GZ) may be the center of melon fruit fly in the southeast China region.
瓜实蝇，Bactrocera cucurbitae (Coquillett)（双翅目：实蝇科），是一种广泛分布的农业害虫，已知有在各种热带和亚热带地区建立入侵种群的潜力。尽管这种蝇类的稳定存在带来了经济风险，但在亚洲这个主要分布区，该害虫的种群遗传学仍未得到充分研究。本研究的目的是利用核标记来研究地理种群的遗传结构，并量化这些东南亚和中国种群内的基因流动程度。为了实现这些目标，我们使用了 12 个多态性微卫星标记。在中国和东南亚的采集品系中发现了较低水平的遗传多样性。贝叶斯模型聚类方法、系统发育重建和主坐标分析结果显示，存在三个遗传上明显不同的群体，即东南亚、中国西南部和中国东南部。Mantel 检验清楚地表明，地理距离对 B. cucurbitae 种群的遗传结构有贡献。没有发现任何种群近期出现瓶颈。聚类、迁移分析和 Mantel 检验的结果强烈表明，观察到的区域结构可能是由于地理因素，如山脉、河流和岛屿造成的。我们发现中国西南部（集群 1）和中国东南部（集群 2）一些地区的迁移率很高，这表明中国-广东-广州（GZ）可能是中国东南部瓜实蝇的中心。
