Chemical Ecology of Plant-Pest Interactions: A Community Approach

由于缺乏移动性，植物不得不对不断变化的环境条件和虫害、疾病等压力做出动态反应。大多数研究都是孤立地检查对单个敌人物种的反应。然而，植物受到昆虫和疾病群落的攻击。许多研究表明，植物对各种敌人反应的关键生化机制有相当大的重叠。我们假设重叠的植物反应通常会对多个敌人产生重叠的影响，从而决定哪些害虫会在空间或时间的任何点上真正侵扰植物。我们将通过研究几种黄瓜品种对病虫害的反应来验证这一假设。我们把重点放在黄瓜上，因为它们的抗性机制、害虫和病原体都得到了充分的研究。首先，我们将描述单个植物对病毒、细菌和真菌感染和四种黄瓜食性昆虫之一的侵染的生化反应的重叠。然后，我们将用每一种其他害虫“挑战”这些有反应的植物，并确定哪些生化机制对一种以上的害虫提供“交叉抗性”。最后，通过将田间生长的幼苗暴露于与上述相同的侵染/侵染处理中，然后允许害虫群落在整个生长季节自然发展，评估害虫群落积累和植物产量，来评估“杂交”或广义抗性因子的生态重要性。这项研究将把植物、昆虫和植物疾病之间的相互作用置于一个现实的社区背景下。广泛的目标是发展一种预测性的植物-害虫科学，这将提供改进的植物育种、基因工程和种植实践，以提高害虫抗性和减少作物损失，以及了解植物-害虫相互作用的发展。

9420013 Schultz Because they lack mobility, plants have had to develop dynamic responses to changing environmental conditions and stresses such as insects and disease. Most studies have examined responses to individual enemy species in isolation. However, plants are attacked by communities of insects and diseases. Many studies reveal considerable overlap in the key biochemical mechanisms of plant responses to various enemies. We hypothesize that overlapping plant responses frequently yield overlapping effects on multiple enemies, determining which pests will actually infest a plant at any point in space or time. We will test this hypothesis by examining the responses of several cucumber varieties to insect pests and diseases. We focus on cucumbers because they have well-studied resistance mechanisms, insect pests, and pathogens. First, we will characterize overlap in biochemical responses of individual plants to infection by a virus, bacterium, and fungus, and infestation with one of four cucumber-feeding insects. We will then "challenge" these responding plants with each of the other pests and determine which biochemical mechanisms provide "cross resistance" to more than one. Finally, the ecological importance of "crossed" or generalized resistance factors will be assessed by exposing young field-grown plants to the same infection/infestation treatments as above, but then allowing natural development of the pest community throughout the growing season, assessing both pest community accumulation and plant yield. This research will put interactions among plants, insects, and plant diseases into a realistic community context. The broad goal is developing a predictive plant-pest science that will provide improved plant breeding, genetic engineering, and cultivation practices for improved pest resistance and reduced crop losses, as well as understanding the development of plant-pest interactions.