Itoh Yuki, Okumura Yukiko, Fujii Takeshi, Ishikawa Yukio, Ômura Hisashi
Graduate School of Biosphere Science, Hiroshima University, Higashihiroshima, Hiroshima, 739-8528, Japan.
Laboratory of Applied Entomology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, 113-8657, Japan.
J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2018 Feb;204(2):245-255. doi: 10.1007/s00359-017-1237-x. Epub 2017 Dec 1.
Mating might significantly affect the host selection behaviors of phytophagous insects. Here, we investigated the post-mating changes in behavioral and antennal responses of Pieris rapae (Lepidoptera: Pieridae) females to host plant volatiles. In two-choice bioassays using artificial plant models, mated females visited the model scented with synthetic blends (15-, 9-, or 6-components) of cabbage plant volatiles more frequently than the unscented control, whereas virgin females did not exhibit this preference. Because single compounds and the 3-component blend did not induce preferential visiting, mated females apparently utilized complex odor blends as their host-finding cue. Moreover, 2- to 4-day-old mated females visited the models, scented and unscented, more frequently than did their virgin counterparts. Therefore, mating enhanced the host-finding behavior of young females and their responsiveness to plant volatiles. Gas chromatography-electroantennographic detector analysis revealed that eight of the 15 compounds in the cabbage plant volatiles elicited responses from female antennae. However, post-mating and age-dependent changes in antennal responses were not detected. Because female peripheral (antennal) sensitivity to volatiles remained practically unchanged after emergence, post-mating changes in host selection might be attributed to changes in the central nervous system.
交配可能会显著影响植食性昆虫的寄主选择行为。在此，我们研究了菜粉蝶（鳞翅目：粉蝶科）雌虫交配后对寄主植物挥发物的行为和触角反应变化。在使用人工植物模型的双选生物测定中，已交配雌虫比未交配雌虫更频繁地访问用甘蓝植物挥发物的合成混合物（15种、9种或6种成分）加香的模型，而未交配雌虫没有表现出这种偏好。由于单一化合物和3种成分的混合物不会诱导优先访问，已交配雌虫显然利用复杂的气味混合物作为其寻找寄主的线索。此外，2至4日龄的已交配雌虫比未交配雌虫更频繁地访问加香和未加香的模型。因此，交配增强了年轻雌虫的寻找寄主行为及其对植物挥发物的反应性。气相色谱-触角电位检测分析表明，甘蓝植物挥发物中的15种化合物中有8种引起了雌虫触角的反应。然而，未检测到交配后和年龄依赖性的触角反应变化。由于雌虫羽化后对挥发物的外周（触角）敏感性基本保持不变，交配后寄主选择的变化可能归因于中枢神经系统的变化。
