Dissertation Research: Ecological and Evolutionary Constraints to Herbivore Resistance in a Native Plant - Mulitiple Herbivore Community

[00:73176]虽然物理和化学防御使植物对其环境中几乎所有潜在的天敌具有免疫力，但大多数植物仍然受到能够克服这些防御的食草动物群落的攻击。进化生态学中的一个主要问题是，是什么阻止了植物进化出更好的食草性。本研究的论点是，只有通过检查以寄主植物为食的整个食草动物群落，才能揭示抗性进化的潜在限制。本研究将通过对马蹄莲（Solanum carolinense）食草昆虫群落的一系列野外实验，通过评估抗性的遗传变异，表征抗性的自然选择，以及研究昆虫与寄主植物之间的生态相互作用来研究这些制约因素。本研究解决了有关植物-食草动物共同进化和食草昆虫之间潜在竞争性质的基本科学问题。此外，马蹄莲是一种经济上重要的杂草，它与许多作物物种的密切亲缘关系使它成为许多作物害虫的储存库。因此，本研究也将为杂草控制和病虫害管理项目提供有价值的信息。

0073176RausherWhile physical and chemical defenses provide plants with immunity from nearly all of the potential natural enemies in their environment, most plants are still attacked by a community of herbivores that are able to overcome these defenses. A major question in evolutionary ecology is what prevents plants from evolving improved resistance to herbivory. The thesis of this research is that there are potential constraints on the evolution of resistance that are revealed only by examining the entire community of herbivores that feed on a host plant. Through a series of field experiments using the insect herbivore community of horsenettle (Solanum carolinense), this research will investigate these constraints by assessing genetic variation for resistance, characterizing natural selection acting on resistance, and investigating the ecological interactions among the insects and their host plant.This research addresses basic scientific questions regarding plant-herbivore coevolution and the nature of potential competition among plant-eating insects. In addition, horsenettle is an economically important weed, and its close kinship with a number of crop species enables it to act as a reservoir for a number of crop pests. Therefore, this research will also provide information that is of interest to weed control and pest management programs.