Chemical Ecology of Resin Secretion in Dalechampia (Euphorbiacea): Radical Evolutionary Shifts in the Functions of Triterpenses?

植物次生化学物质介导了植物与植物之间的许多关系。 植物和它们的互利者和拮抗者。 数量和 这些植物与动物关系的特殊性产生了许多 热带地区的生物多样性。 植物通常使用二级 作为防御食草动物或作为引诱剂 互助主义者 化学上相似的化合物可能有不同的作用 在相关植物中发挥作用。 拟议的研究将 通过测试阐明植物-动物相互作用的模型系统 这种假设认为，萜类树脂，其功能是花， 在大多数Dalechampia物种中，蜜蜂的奖励， 原始种的叶、托叶和花的小苞片， 防御食草动物和/或病原体，并且在 授粉 Rhopalostylis的原始种，根据 这一假设，应该保护花和叶， 食草动物与树脂，同时提供传粉者一些其他 奖励，如花粉或香料。 为了验证这些想法， 拟议的项目将i）确定萜类化合物是否 无腺体和有腺体物种的树脂阻止食草动物， 通过在饲养试验中使用树脂提取物， 食草动物; ii）确定是否萜烯树脂 抑制微生物，通过在生物测定中测试提取物， 微生物; iii）研究化学关系 植物和植物树脂之间的关系， 分析产生的化合物;和iv）观察 无腺体植物的授粉和食草 Dalechampia的种类 这项研究的信息将给我们 更深入地了解动植物的化学基础 互动，这种互动如何演变，以及如何新颖 互惠生。

Plant secondary chemicals mediate many relationships between plants and their mutualists and antagonists. The number and specificity of these plant-animal relationships generates much of the biodiversity of the tropics. Plants commonly use secondary compounds as defense against herbivores or as attractants for mutualists. Chemically similar compounds may serve different functions in related plants. The proposed research will elucidate a model system of plant-animal interactions by testing the hypothesis that terpenoid resins, which function as floral rewards for bees in most species of Dalechampia, function in the leaves, stipules, and floral bractlets of primitive species as a defense against herbivores and/or pathogens, and play no role in pollination. Primitive species of Rhopalostylis, according to the hypothesis, should defend flowers and leaves against herbivores with resin, while offering pollinators some other reward, such as pollen or fragrances. To test these ideas the proposed project will i) establish whether or not the terpenoid resins of glandless and gland-bearing species deter herbivores, by using resin extracts in feeding trials with natural herbivores; ii) establish whether or not the terpenoid resins inhibit microorganisms, by testing extracts in bioassays with microorganisms; iii) investigate the chemical relationships between the floral and vegetative resins by surveying and analyzing the compounds produced; and iv) make observations on the pollination of, and herbivory on, primitively glandless species of Dalechampia. Information from this study will give us greater insight into the chemical basis of plant-animal interactions, how such interactions evolve, and how novel mutualisms arise.