荻草谷网蚜是一种在中国温带地区对小麦作物最具破坏性的蚜虫。但是关于这种蚜虫的遗传结构以及不同地理位置对种群的影响却知之甚少。在本研究中，我们通过使用一个线粒体基因COI，一个核基因EF-1α，以及两个内共生菌布赫纳氏菌基因gnd和trpA分析了中国18个地理种群，从而研究了荻草谷网蚜的种群遗传结构和种群历史动态。各群体的数据分析显示单倍型多样性高，核苷酸变异低。SAMOVA分析没有发现遗传距离和地理距离之间的相关性。然而，种群多样性较高的地区具有较高的单倍型多样性。因此，我们推测，在中国荻草谷网蚜的自然迁移途径主要有两条。一条路径是从云南到四川盆地，另外一条是从武汉、信阳、胶东半岛地区到西北地区。基于这一假设，我们推断这些蚜虫首先出现在西南和南部地区，并在东南和西南季风的帮助下于春夏季在北方发生。秋季，蚜虫随东北和西北季风向南扩散。

The full-length cDNA of functionally-unknown salivary protein C002 in Schizaphis graminum was cloned using rapid amplification of cDNA ends (RACE) and designated as SgC002 (GenBank accession no. KC977563). It is 767 bp long and encodes a protein of 190 amino acid residues with a predicted mass of 21.5 kDa and a predicted cleavage site of N-terminal signal peptide between the 24th and the 25th residues. SgC002 is specifically expressed in salivary gland with the highest level at the 2nd instar. Introducing SgC002-specific 476-siRNA, but not 546-siRNA to aphids through artificial diet significantly suppressed SgC002 expression. Silencing SgC002 gene led to lethality of the aphid on wheat plants, but not on pure artificial diet. Our study demonstrated that artificial diet-mediated RNAi can be a useful tool for research on the roles of genes in aphid salivary gland, and also provided new insights into the characteristics of C002 in wheat aphids.