Dissertation Research: Control of Insect Populations by Generalist Predators: Impact of Intraguild Predation

[9701180] Wise这项拟议的研究将调查多面手地面捕食者——狼蛛（Lycosidae）和地甲虫（Carabidae）——对蔬菜害虫的捕食动态。Carabids和lycosidids是一种广泛的食草动物，它们也互相捕食——这种行为被定义为内部捕食（IGP）。将解决四个具体问题：(1)石松类和甲壳类的捕食是否会抑制食草昆虫的密度？(2)石蜡类和石蜡类是否对其他捕食者种群产生负面影响？(3) IGP是否限制石蜡果苷和石蜡果苷的数量？(4)陆食动物种群的大小结构是否影响其对食草动物种群的影响？可操作的田间试验将通过控制石松类和瓢虫向围栏菜园的迁移，观察对害虫密度、其他捕食者密度和植物生产力的影响来解决上述问题。实地试验将辅以实验室喂养试验。该研究将阐明IGP在多大程度上限制了多面手捕食者对食草动物密度的影响。由于这项研究将在一个农业系统中进行，其结果将增进对本土多面手捕食者作为生物防治剂的局限性和优势的了解，这将有助于更有效地利用它们进行病虫害综合治理。

9701180 Wise The proposed research will investigate the dynamics of predation by generalist ground predators - wolf spiders (Lycosidae) and ground beetles (Carabidae) - on insect pests of vegetables. Carabids and lycosids, which consume a wide spectrum of herbivore species, also prey on each other - behavior defined as intraguild predation (IGP). Four specific questions will be addressed: (1) Does predation by lycosids and carabids suppress densities of herbivorous insects? (2) Do lycosids and carabids negatively impact populations of other predators? (3) Does IGP limit carabid and lycosid populations? (4) Does the size structure of the ground-predator guild influence its impact on herbivore populations? Manipulative field experiments will address the above questions by controlling immigration of lycosids and carabids into fenced vegetable gardens, and observing effects on pest densities, densities of other predators, and plant productivity. The field experiments will be complemented with laboratory feeding trials. The research will elucidate the extent to which IGP limits the impact of generalist predators on herbivore densities. Since the study will be conducted in an agricultural system, results will improve understanding of the limitations and strengths of indigenous generalist predators as biological control agents, which will contribute to their more effective use in integrated pest management.