Wu Han, Xu Meng, Hou Chao, Huang Ling-Qiao, Dong Jun-Feng, Wang Chen-Zhu
State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences Beijing, China.
State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences Beijing, China ; Department of Plant Protection, Forestry College, Henan University of Science and Technology Luoyang, China.
Front Behav Neurosci. 2015 Aug 4;9:206. doi: 10.3389/fnbeh.2015.00206. eCollection 2015.
Sex pheromone communication of moths helps to understand the mechanisms underlying reproductive isolation and speciation. Helicoverpa armigera and Helicoverpa assulta use (Z)-11-hexadecenal (Z11-16:Ald) and (Z)-9-hexadecenal (Z9-16:Ald) as pheromone components in reversed ratios, 97:3 and 5:95, respectively. H. armigera also produces trace amount of (Z)-9-tetradecenal (Z9-14:Ald) in the sex pheromone gland, but H. assulta does not. Wind tunnel studies revealed that the addition of small amounts (0.3%) of Z9-14:Ald to the main pheromone blend of H. armigera increased the males' attraction, but at higher doses (1%, 10%) the same compound acted as an inhibitor. In H. assulta, Z9-14:Ald reduced male attraction when presented as 1% to the pheromone blend, but was ineffective at lower concentrations (0.3%). Three types (A-C) of sensilla trichodea in antennae were identified by single sensillum recording, responding to Z11-16:Ald, Z9-14:Ald, and both Z9-16:Ald and Z9-14:Ald, respectively. Calcium imaging in the antennal lobes (ALs) revealed that the input information of the three chemicals was transmitted to three units of the macroglomerular complex (MGC) in ALs in both species: a large glomerulus for the major pheromone components, a small one for the minor pheromone components, and a third one for the behavioral antagonists. The type A and C neurons tuned to Z11-16:Ald and Z9-16:Ald had a reversed target in the MGC between the two species. In H. armigera, low doses (1, 10 μg) of Z9-14:Ald dominantly activated the glomerulus which processes the minor pheromone component, while a higher dose (100 μg) also evoked an equal activity in the antagonistic glomerulus. In H. assulta, instead, Z9-14:Ald always strongly activated the antagonistic glomerulus. These results suggest that Z9-14:Ald plays different roles in the sexual communication of two Helicoverpa species through activation of functionally different olfactory pathways.
蛾类的性信息素通讯有助于理解生殖隔离和物种形成的潜在机制。棉铃虫和烟青虫分别以97:3和5:95的相反比例使用（Z）-11-十六碳烯醛（Z11-16:Ald）和（Z）-9-十六碳烯醛（Z9-16:Ald）作为性信息素成分。棉铃虫在性信息素腺体中也会产生微量的（Z）-9-十四碳烯醛（Z9-14:Ald），但烟青虫不会。风洞研究表明，向棉铃虫的主要性信息素混合物中添加少量（0.3%）的Z9-14:Ald会增加雄性的吸引力，但在较高剂量（1%、10%）时，相同的化合物会起到抑制剂的作用。在烟青虫中，当以1%的比例添加到性信息素混合物中时，Z9-14:Ald会降低雄性的吸引力，但在较低浓度（0.3%）时无效。通过单感器记录在触角中鉴定出三种类型（A-C）的毛形感器，它们分别对Z11-16:Ald、Z9-14:Ald以及Z9-16:Ald和Z9-14:Ald都有反应。触角叶中的钙成像显示，这三种化学物质的输入信息在两个物种中都被传递到触角叶中大体肾小球复合体（MGC）的三个单元：一个大的肾小球用于主要性信息素成分，一个小的用于次要性信息素成分，第三个用于行为拮抗剂。在两个物种之间，调谐到Z11-16:Ald和Z9-16:Ald的A型和C型神经元在MGC中有相反的靶点。在棉铃虫中，低剂量（1、10μg）的Z9-14:Ald主要激活处理次要性信息素成分的肾小球，而较高剂量（100μg）也会在拮抗肾小球中引发同等的活性。相反，在烟青虫中，Z9-14:Ald总是强烈激活拮抗肾小球。这些结果表明，Z9-14:Ald通过激活功能不同的嗅觉通路，在两种棉铃虫的性通讯中发挥不同的作用。
