Department of Entomology, China Agricultural University, Yuanmingyuan West Road, Beijing 100193, China.
J Econ Entomol. 2012 Apr;105(2):583-91. doi: 10.1603/ec11368.
The spiraea aphid (Aphis spiraecola Patch) is a primary pest of fruit trees, particularly pear trees in China. Despite the economic importance of this pest, little is known about its genetic structure or its patterns of dispersal at local and regional scales; however, knowledge of these characteristics is important for establishing effective control strategies for this pest. The genetic variability of 431 individuals from 21 populations on pear trees in China was investigated using eight polymorphic microsatellite loci. The high polymorphism of these markers was evident from the expected heterozygosity value (He = 0.824) and the Polymorphism Information Content (PIC = 0.805), indicating that the spiraea aphid maintains a high level of genetic diversity. The analysis of molecular variance revealed a middle level of population differentiation (F(ST) = 0.1478) among A. spiraecola populations. This result is consistent with the results of the STRUCTURE analysis (K = 3), the unweighted pair-group method with arithmetic average tree and the Mantel test (r = 0.6392; P < 0.05). Our results indicate high levels of genetic exchange in the spiraea aphid, possibly facilitated by geography and climate. Our findings emphasize the importance of considering regional differences in studies of population structure, even when strong isolation-by-distance influences the genetic population structure of species.
梨树上的绣线菊蚜（Aphis spiraecola Patch）是一种主要的果树害虫，在中国尤其对梨树危害严重。尽管这种害虫具有重要的经济意义，但对其遗传结构及其在局部和区域尺度上的扩散模式知之甚少；然而，了解这些特征对于制定该害虫的有效防治策略非常重要。本研究利用 8 个多态性微卫星标记，对中国 21 个梨树上的 431 个绣线菊蚜个体的遗传变异进行了调查。这些标记的高多态性从预期杂合度值（He = 0.824）和多态信息含量（PIC = 0.805）中得到明显体现，表明绣线菊蚜保持着高水平的遗传多样性。分子方差分析显示，A. spiraecola 种群之间存在中等水平的种群分化（F（ST）= 0.1478）。这一结果与 STRUCTURE 分析（K = 3）、非加权组平均法（unweighted pair-group method with arithmetic average tree）和 Mantel 检验（r = 0.6392；P < 0.05）的结果一致。我们的结果表明，绣线菊蚜具有高水平的遗传交换，这可能是由地理和气候因素促成的。我们的研究结果强调了在种群结构研究中考虑区域差异的重要性，即使强的距离隔离对物种的遗传种群结构有影响。
