Parsnip Webworms as Selective Agents On Primary Metabolites of Wild Parsnip

9509826 Berenbaum引种的植食性昆虫防己网虫和野草防风之间的相互作用是对昆虫在寄主植物中选择化学抗性的能力进行估计的极少数自然系统之一。到目前为止，人们对这一系统的关注集中在呋喃香豆素的作用上，呋喃香豆素是植物产生的杀虫化合物，在赋予对该害虫的抗性方面发挥作用。这项提议的重点是确定昆虫草食动物是否选择了植物初级代谢物，这些代谢物可能作为昆虫的营养物质。近二十年来，植物营养质量可以随着昆虫食草性的反应而进化的假说实际上一直没有得到检验。这项研究是少数几个研究植物初级代谢物变化对昆虫抗性的影响的研究之一，因此可以用来评估这一假说及其对植物/昆虫相互作用研究的意义。除了对基础研究的重要性外，该项目还对消耗农作物的害虫物种的管理产生了影响。目前有兴趣开发新的机制来减少农业生态系统中的虫害问题，同时减少对这些系统的化学投入。由于人类并不像许多植食性昆虫那样只以单一植物物种为食，因此在没有化学投入的情况下，对植物中营养水平进行选择性育种可能会减少昆虫的损害，对人类消费者几乎没有不利影响。

9509826 Berenbaum The interactions between the parsnip webworm, an introduced plant-feeding insect, and the wild parsnip, an introduced weed that serves as its principal host throughout its range, is one of very few natural systems in which estimates have been made of the ability of an insect to select for chemically based resistance in its hostplant. To date, attention in this system has focused on the role of furanocoumarins, insecticidal compounds produced by the plant, in conferring resistance against the insect. The focus of this proposal is to determine whether plant primary metabolites, which may serve as nutrients for insects, are under selection by insect herbivores. The hypothesis that plant nutritional quality can evolve in response to insect herbivory has remained effectively untested for almost two decades. This study is one of few to examine the consequences of variation in plant primary metabolites on insect resistance and as such can be used to evaluate that hypothesis and its implication for studies of plant/insect interactions. In addition to its importance to basic studies, this project has implications for the management of crop-consuming pest species. There is currently interest in developing novel mechanisms to reduce pest problems in agroecosystems and at the same time reduce chemical inputs to those systems. Because humans do not feed exclusively on a single plant species, as do many phytophagous insects, selective breeding for altered nutrient levels in plants may lead to reductions in insect damage in the absence of chemical inputs, with little or no adverse impacts on human consumers.