Department of Horticulture, College of Tea and Food Science, Wuyi University, Wuyishan 354300, PR China.
Biological Control Research Institute, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China.
J Insect Sci. 2021 May 1;21(3). doi: 10.1093/jisesa/ieab036.
Aphidius gifuensis Ashmaed is a generalist endoparasitoid that parasitizes a variety of aphid species. In China, it is widely used as a biological control agent to protect vegetables and tobaccos in open fields; control efficiency is largely dependent on its host-seeking ability. In this study, a six-choice olfactometer was used to investigate the olfactory responses of A. gifuensis to tobacco plants that had suffered damage (either varying degrees of mechanical damage or from aphid-feeding at different time intervals) and tobacco volatiles with different dosages. Furthermore, the regularity of A. gifuensis females' response toward an aphid/tobacco complex was monitored using a Y-tube olfactometer. Our findings suggest that tobacco plants are significantly attractive to A. gifuensis after they have been punctured with 50 holes, or housed with Myzus persicae (Sulzer) at a density of 400 aphids, except at an infestation time of 12 h. Moreover, aphid density had a more significant effect on the response than the time interval since aphid application. Aphidius gifuensis was found to be active during the daytime and preferred to search for their aphid hosts at 14:00 h. Five EAG-active tobacco volatiles (trans-2-hexenal, methyl salicylate, benzaldehyde, cis-3-hexen-1-ol, and 1-hexanal) were found to significantly attract A. gifuensis females at different concentration ranges. The practical implications of these results are discussed in the framework of the sustainable biological control of pest aphids in agricultural production systems.
异色瓢虫（Aphidius gifuensis Ashmaed）是一种广食性内寄生蜂，可寄生多种蚜虫。在中国，它被广泛用作生物防治剂来保护露天蔬菜和烟草；控制效率在很大程度上取决于其寻找宿主的能力。在这项研究中，使用六臂嗅觉仪研究了异色瓢虫对遭受不同程度机械损伤或不同时间间隔取食蚜虫的烟草植株以及不同剂量烟草挥发物的嗅觉反应。此外，使用 Y 型嗅觉仪监测了异色瓢虫雌蜂对蚜虫/烟草复合体的反应规律。我们的研究结果表明，烟草植株在被刺 50 个孔或每平方米饲养 400 头桃蚜（Myzus persicae （Sulzer））后，除了在 12 小时的侵害时间外，对异色瓢虫具有显著的吸引力。此外，蚜虫密度对反应的影响比蚜虫应用后的时间间隔更为显著。异色瓢虫在白天活跃，在 14:00 时更喜欢寻找它们的蚜虫宿主。发现五种 EAG 活性烟草挥发物（反-2-己烯醛、甲基水杨酸酯、苯甲醛、顺-3-己烯-1-醇和 1-己醛）在不同浓度范围内显著吸引异色瓢虫雌蜂。这些结果在农业生产系统中对可持续控制害虫蚜虫的生物防治方面具有实际意义。
