Dissertation Research: Effects of Enriched CO2 Environments on Plants and Insects: Herbivory and Resource Allocation

模拟富集CO2大气的能力提供了一个独特的机会：1)在这些条件下研究植物/草食动物相互作用的动力学；2)研究碳氮有效度控制下的植物配置模式。我们将研究在二氧化碳浓度增加的环境中，食草动物以植物为食的营养生态学和适应性。此外，还将比较不同CO2条件下食草动物对植物适应度的影响。车前草（车前草科）是一种多年生草本植物，含有环烯醚萜苷，而一种特殊的草食动物，用这些化合物作为取食和产卵的刺激物，将成为研究这些相互作用的一个很好的系统。为了研究碳和氮资源在生长、繁殖和防御方面的平衡分配，我们将在不同的碳（CO2）和氮可用性条件下生长两种植物，它们含有不同种类的化感物质。将测定杉木（含有环烯醚萜苷）和毛地黄(含有氮基（生物碱）和碳基（酚类和环烯醚萜苷）的化感物质的生长、繁殖产量和化感物质含量。

The ability to simulate enriched CO2 atmospheres provides a unique opportunity to: 1) study the dynamics of plant/herbivore interactions under these conditions; and 2) examine plant allocation patterns under controlled carbon and nitrogen availabilities. The nutritional ecology and fitness of herbivores feeding on plants grown in enhanced CO2 environments over several generations will be investigated. In addition, the effects of herbivores on plant fitness under different CO2 conditions will be compared. Plantago lanceolata (Plantaginaceae), a herbaceous perennial which contains iridoid glycosides, and a specialist herbivore, Junonia coenia (Lepidoptera: Nymphalidae), which uses these compounds as feeding and oviposition stimulants, will serve as an excellent system to study these interactions. To examine trade-offs in allocation of carbon and nitrogen resources to growth, reproduction, and defense, individuals of two plant species, differing in the classes of allelochemicals they contain, will be grown under varying carbon (CO2) and nitrogen availabilities. Growth, reproductive output and allelochemical content will be determined for P. lanceolata (which contains iridoid glycosides) and Penstemon digitalis (Scrophulariaceae) which contains both nitrogen-based (alkaloids) and carbon-based (phenolics and iridoid glycosides) allelochemicals.