Collaborative Research: Plant Secondary Metabolites as Mediators of Trophic Interactions in a Tropical Forest Community.

研究土壤质量、光效、植物化学和昆虫丰度如何相互作用是理解生态系统功能的重要组成部分。热带雨林的灌木，Piper cenocladum和它的伴生昆虫对这类研究是有用的。花椒为蚂蚁提供食物和庇护所，保护蚂蚁免受昆虫食草动物的侵害，它产生的几种毒素随着土壤质量和光照的适度增加而增加。先前对该系统的研究表明，蚂蚁控制了专门的食草昆虫，而植物毒素阻止了更广泛饮食的昆虫的食草性。这些结果是这种不寻常的反植物共生关系所特有的，还是在许多雨林下层植物中都可能发生的常见现象？作为探索先前结果的普遍性的一步，拟议的研究将检查昆虫、土壤和光对一种密切相关的植物物种的影响，这种植物物种尚未与蚂蚁进化成共生关系。生态学家和化学家之间拟议的合作将允许对昆虫捕食者与植物毒素在控制昆虫食草动物中的作用进行深入研究。研究结果将为生态学理论提供有价值的信息，并为保护生物学和农业的实际决策提供指导。

Studying how soil quality, light availability, plant chemistry, and insect abundance interact is an important component of understanding how ecosystems function. The rain forest shrub, Piper cenocladum, and its associated insects have been useful for such studies. Piper cenocladum provides food and shelter for ants that protect it from insect herbivores, and it produces several toxins that increase with moderate increases in soil quality and light availability. Previous research with this system demonstrated that the ants controlled specialized insect herbivores, while the plant toxins deterred herbivory by insects with broader diets. Are these results unique to this unusual ant-plant mutualism or are these common phenomena that can happen in many rain forest understory plants? As one step towards exploring the generality of previous results, the proposed study will examine the effects of insects, soil, and light on a closely related plant species that has not evolved a mutualism with ants. The proposed collaboration between ecologists and chemists will allow for a thorough study examining the roles of insect predators versus plant toxins in controlling insect herbivores. Results from the work will provide valuable information for ecological theory and guidance for practical decisions in conservation biology and agriculture.