Rothamsted Research, Harpenden, Herts AL5 2JQ, UK.
Biol Lett. 2010 Jun 23;6(3):314-7. doi: 10.1098/rsbl.2009.0953. Epub 2009 Dec 23.
Plants subjected to insect attack usually increase volatile emission which attracts natural enemies and repels further herbivore colonization. Less is known about the capacity of herbivores to suppress volatiles and the multitrophic consequences thereof. In our study, the African forage grass, Brachiaria brizantha, was exposed to ovipositing spotted stemborer, Chilo partellus, moths. A marked reduction in emission of the main volatile, (Z)-3-hexenyl acetate (Z3HA), occurred following oviposition but the ratio of certain other minor component volatiles to Z3HA was increased. While further herbivore colonization was reduced on plants after oviposition, the new volatile profile caused increased attraction of an adapted parasitoid, Cotesia sesamiae. Our results show that insect responses are dependent on the quality of volatile emission rather than merely the quantity in this multitrophic interaction.
遭受昆虫攻击的植物通常会增加挥发性排放，这会吸引天敌并阻止进一步的食草动物定殖。然而，关于食草动物抑制挥发物的能力及其多营养级后果的了解较少。在我们的研究中，非洲草料 Brachiaria brizantha 暴露于产卵的斑点茎螟 Chilo partellus 飞蛾中。产卵后，主要挥发性物质（Z）-3-己烯基乙酸酯（Z3HA）的排放明显减少，但某些其他次要成分挥发物与 Z3HA 的比例增加。虽然进一步的食草动物定殖在产卵后减少，但新的挥发性特征导致适应的寄生蜂 Cotesia sesamiae 的吸引力增加。我们的结果表明，昆虫的反应取决于挥发性排放的质量，而不仅仅是这种多营养级相互作用中的数量。
