Department of Entomology, University of Minnesota, St. Paul, MN 55108, USA.
J Chem Ecol. 2009 Sep;35(9):1108-16. doi: 10.1007/s10886-009-9683-8. Epub 2009 Sep 8.
Social insects that live in large colonies are vulnerable to disease transmission due to relatively high genetic relatedness among individuals and high rates of contact within and across generations. While individual insects rely on innate immune responses, groups of individuals also have evolved social immunity. Hygienic behavior, in which individual honeybees detect chemical stimuli from diseased larvae and subsequently remove the diseased brood from the nest, is one type of social immunity that reduces pathogen transmission. Three volatile compounds, collected from larvae infected with the fungal pathogen Ascosphaera apis and detected by adult honey bees, were identified by coupled gas chromatography-electroantennographic detection and gas chromatography-mass spectrometry. These three compounds, phenethyl acetate, 2-phenylethanol, and benzyl alcohol, were present in volatile collections from infected larvae but were absent from collections from healthy larvae. Two field bioassays revealed that one of the compounds, phenethyl acetate is a key compound associated with Ascosphaera apis-infected larvae that induces hygienic behavior.
群居的社会性昆虫由于个体间遗传相关性较高，且个体间及代际间的接触频率较高，因此易受到疾病传播的影响。虽然个体昆虫依赖先天免疫反应，但群体昆虫也进化出了社会免疫。卫生行为是一种社会免疫，即个别蜜蜂从患病幼虫身上检测到化学刺激物，然后将患病的幼虫从巢中移走，从而降低病原体的传播。从感染真菌病原体 Ascosphaera apis 的幼虫中收集到的三种挥发性化合物，被成年蜜蜂检测到，然后通过气相色谱-触角电位检测和气相色谱-质谱联用技术进行鉴定。这三种化合物，乙酸苯乙酯、2-苯乙醇和苯甲醇，存在于感染幼虫的挥发性混合物中，但不存在于健康幼虫的混合物中。两项野外生物测定表明，其中一种化合物，乙酸苯乙酯，是一种与感染 Ascosphaera apis 的幼虫相关的关键化合物，它能诱导卫生行为。
