State Key Laboratory of Crop Stress Biology for Arid Areas, Northwest A&F University, Yangling, Shaanxi, China.
College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China.
J Econ Entomol. 2019 May 22;112(3):1217-1226. doi: 10.1093/jee/toy426.
The English grain aphid, Sitobion avenae (Fabricius), is a cosmopolitan insect pest on cereals. Many studies on life-history traits indicate that S. avenae clones from different areas have diverged on various host plants. However, direct genetic evidence for this phenomenon is rare. Thus, S. avenae clones were collected from barley (Hordeum vulgare L.) and wheat (Triticum aestivum L.) in four provinces (i.e., Hubei, Henan, Jiangsu, and Zhejiang) of China, and characterized using six microsatellite markers. In total, 92 multilocus genotypes were found from 302 individuals of S. avenae. Population Jiangsu was found to have relatively high levels of genotypic diversity among the four geographical populations. Substantial long-distance migration of S. avenae was found from Zhejiang to the other three provinces. Thus, relatively low genetic differentiation was found between these geographic populations. Barley clones of S. avenae showed higher gene diversity compared with wheat clones. The gene flow from barley to wheat clones appeared to be more likely than that in the reverse direction. Diversity indices and structure for S. avenae clones suggested highest level of genetic divergence between barley and wheat clones in Jiangsu among all sampling locations. Besides Jiangsu, pairwise FST values indicated moderate levels of genetic divergence between barley and wheat clones in Zhejiang. Thus, compared with geographical factors, plant factors could be relatively more important in promoting genetic differentiation in S. avenae. Our results provide insights into genetic differentiation of S. avenae on different plants, as well as a basis for exploring the molecular mechanism for its differentiation on plants and biotype development.
禾谷缢管蚜（Sitobion avenae）是一种世界性的谷类害虫。许多关于生活史特征的研究表明，来自不同地区的 S. avenae 克隆在各种宿主植物上已经发生了分化。然而，这种现象的直接遗传证据很少。因此，从中国四个省份（湖北、河南、江苏和浙江）的大麦（Hordeum vulgare L.）和小麦（Triticum aestivum L.）中收集了 S. avenae 克隆，并使用六个微卫星标记进行了特征描述。总共从 302 个 S. avenae 个体中发现了 92 个多基因座基因型。四个地理种群中，江苏种群的基因型多样性相对较高。从浙江到其他三个省份发现了大量的 S. avenae 远距离迁移。因此，这些地理种群之间的遗传分化相对较低。与小麦克隆相比，大麦克隆的 S. avenae 显示出更高的基因多样性。大麦向小麦克隆的基因流动似乎比反向方向更有可能。S. avenae 克隆的多样性指数和结构表明，在所有采样地点中，江苏的大麦和小麦克隆之间的遗传分化水平最高。除了江苏，成对的 FST 值表明在浙江，大麦和小麦克隆之间存在中度的遗传分化。因此，与地理因素相比，植物因素可能在促进 S. avenae 的遗传分化方面更为重要。我们的研究结果为 S. avenae 在不同植物上的遗传分化提供了新的见解，也为探索其在植物上的分化和生物型发育的分子机制提供了基础。
