Dissertation Research: Influence of Population Dynamics and Community Interactions on Mutualistic Outcomes in an Obligate Pollination Mutualism

9800885 Strauss影响植食性的植物性状通常不考虑对授粉的影响，反之亦然。这可能导致对这些性状的选择的不完全理解。两种Castilleja hemiparasis，它可以从羽扇豆寄主植物中获得生物碱，将被用来测试是否对食草动物的化学防御也阻止传粉者。Castilleja物种将与同种羽扇豆的低生物碱或高生物碱品种一起生长，以测试生物碱吸收对草食动物和授粉的影响。初步的数据支持这一假设，这是一个生态之间的权衡草食动物的防御和传粉者的吸引力。如果存在这样的权衡，它表明了限制化学防御发展的新可能性。该研究在整个植物水平上整合了化学生态学，推进了寄生植物生态学的基础知识，并开发了一种新的方法来评估新型防御化学物质在体内的后果。植物-动物相互作用可能受到多重选择压力的限制这一概念在自然和农业系统中都有广泛的应用。

9800885 Strauss Plant traits that affect herbivory are usually studies without considering effects on pollination, or vice versa. This may result in an incomplete understanding of selection on these traits. Two species of Castilleja hemiparasites, which can obtain alkaloids from Lupinus host plants, will be used to test whether chemical defense against herbivores also deters pollinators. Castilleja species will be grown with either low-alkaloid or high-alkaloid varieties of conspecific lupines to test the consequences of alkaloid uptake on herbivory and pollination. Preliminary data support the hypothesis that these is an ecological tradeoff between herbivore defense and pollinator attraction. If such a tradeoff exists, it suggests new possibilities for constraints on the development of chemical defenses. The proposed research integrates chemical ecology at the whole plant level, advances basic knowledge of the ecology of parasitic plants, and develops a new methods to assess consequences of novel defensive chemicals in vivo. The concept that plant-animal interactions may be constrained by multiple selection pressures has broad applications in both natural and agricultural systems.