QEIB: Predicting the Effects of Diffusion-limitation in a Predator-prey System

用于预测物种相互作用的生态学理论通常不考虑小尺度空间结构的影响。据推测，捕食者的成功，如瓢虫，或多或少是相同的，无论他们是在玉米植物或豌豆植物上发现的。这种假设不符合我们对世界的常识性经验。由于空间的复杂性，在某些环境中移动比在其他环境中移动更困难，这种移动性的限制应该会影响物种之间的相互作用，例如捕食者-猎物关系。随着环境变得更加复杂，捕食者和猎物的相遇率应该会降低。因此，以同样的方式，化学反应在复杂介质中减慢（即，由于分子在复杂空间中的缓慢运动，它们是“扩散受限的”），因此我们预期对具有复杂形状的植物的捕食成功率会降低。在拟议的研究中，基于这种期望的模型将被开发和测试使用捕食者-猎物系统，这是重要的农业。天然存在的豌豆突变体已被广泛用于商业用途，然而这些豌豆的更复杂的形状可能会改变益虫的功效。使用豌豆突变体与不同程度的叶片复杂性，作者将研究捕食成功的瓢虫异色瓢虫，一种常用的有益昆虫，在实验室和温室条件下豌豆蚜虫。通过使用这个实验系统，她将同时测试一个新的生态理论，并评估植物形态对生物控制程序的影响。

Ecological theories used to predict species interactions typically do not take into account the effects of small-scale spatial structure. It is assumed that the success of predators, like ladybugs, is more or less the same whether they are found on corn plants or pea plants. This assumption does not fit our commonsense experience of the world. It is harder to move through some environments than others because of spatial complexity, and this limitation of mobility should affect species interactions such as the predator-prey relationship. As environments become more complex the encounter rate of predators and prey should decrease. Therefore, in the same way that chemical reactions slow down in complex media (i.e., they are "diffusion-limited" because of the slow movement of molecules in complex spaces), so to we expect a reduction in predation success on plants with complex shapes. In the proposed research, models based on this expectation will be developed and tested using a predator-prey system that is important in agriculture. Naturally occurring pea mutants have been widely adopted for commercial use, however the more complex shape of these peas may alter the efficacy of beneficial insects. Using pea mutants with differing degrees of leaf complexity, the author will examine the predation success of the ladybug Harmonia axyridis, a commonly used beneficial insect, on pea aphids in laboratory and greenhouse conditions. By using this experimental system she will simultaneously test a new ecological theory and evaluate of the effects of plant morphology on biological control programs.