Herbivore-induced plant volatiles: plant and insect responses

挥发性有机化合物可以在植物生态中发挥主导作用。食草动物诱导的植物挥发物(HIPV)在许多农艺植物中都有很好的文献记载，它们在吸引寄生蜂和捕食者方面发挥了作用，从而为发射植物提供了间接防御。人们还不太清楚的是，HIPV在攻击同一种植物的不同类型的昆虫食草动物中的影响，以及昆虫食草动物是否能习惯于来自宿主植物的这些嗅觉信号。据预测，全球气候变化的关键参数--二氧化碳和温度上升--将改变植物的防御化学，并可能使农作物更容易受到虫害的影响。这些大气因素对HIPV的影响研究很少。我建议从植物、食草动物群落和个体食草动物三个角度来探讨HIPV。具体而言，拟议研究的目标是： 1.研究温室番茄与大田番茄HIPVS的质量和数量差异，以及CO2浓度的增加是否会增加HIPVS； 2.确定HIPV对不同食草动物(飞蛾、蚜虫、粉虱)登陆/定居的影响是积极的(吸引)还是消极的(排斥/威慑)，包括对同种(即诱导物种)的影响； 3.确定食草动物在长期接触HIPV后是否会习惯于HIPV 这些研究将加深我们对HIPV在昆虫-植物相互作用中的作用的理解，特别是关于它们在昆虫草食动物群落生态学中的作用。在实践方面，通过了解植物防御系统如何随着非生物因素的变化，以及昆虫如何在种群和个体基础上对HIPV做出反应，我们可以更好地预测全球气候变化可能如何影响粮食生产。最终，我们可能会转向HIPV，通过操纵害虫种群来更好地管理害虫。

Volatile organic compounds can play a dominant role in the ecology of plants. Herbivore-induced plant volatiles (HIPVs) are well documented for a number of agronomic plants, as is their role in attracting parasitoids and predators, thus providing indirect defense for the emitting plant. What is far less well know is the influence of HIPVs among different types of insect herbivores attacking the same plant, and whether insect herbivores can habituate to these olfactory signals from their host plants. Key parameters of global climate change - increasing CO2 and temperature - are predicted to alter plant defensive chemistry and may make crops more vulnerable to pests. Effects of these atmospheric factors on HIPVs has been little studied. I propose to explore HIPVs from three perspectives, that of the plant, the herbivore community and individual herbivores. Specifically, the objectives of the proposed research are: 1. To determine qualitative and quantitative differences in HIPVs between greenhouse grown and field grown tomato plants of comparable age, and if HIPVs are increased by CO2 enrichment; 2. To determine if HIPVs influence landing/settling by different herbivores (looper moths, aphids, whiteflies) either positively (attraction) or negatively (repellence/deterrence), including influence on conspecifics (i.e. the inducing species); 3. To determine if herbivores can become habituated to HIPVs after prolonged exposure These studies will enhance our understanding of the role of HIPVs in insect-plant interactions, in particular regarding their role in community ecology of insect herbivores. On the practical side, we may better predict how global climate change might impact food production by understanding how plant defences may change in response to abiotic factors, and how insects may in turn respond to HIPVs on a population and individual basis. Ultimately we may be able to turn to HIPVs to better effect pest management via manipulation of pest populations.