Spatial Dynamics of Host/Parasitoid Interactions: Indirect Effects of Aphids

生物体之间的间接相互作用越来越普遍， 许多生态系统的重要因素。 本研究 测试了植食性昆虫相互作用的一般假设， 间接地通过对空间动态的强烈影响， 天敌活动。 特别是，它评估是否 蚜虫（通常是最丰富和广泛的所有 温带生态系统中的植食性昆虫）影响空间 其他昆虫寄生强度的变化; 寄生蜂可能在局部地区积累， 长寿和繁殖力，通过消耗蚜虫蜜露。 昆虫 苜蓿群落提供了一个极好的测试系统。 领域 苜蓿试验将测试豌豆的间接影响 蚜虫对苜蓿象鼻虫，作为介导的寄生蜂 特有的象鼻虫，并受到天敌的影响， 豌豆蚜虫（瓢虫）。 调查间接网络 以及苜蓿昆虫群落中的直接相互作用 提供了机会，不仅可以测试一般 生态利益，而且有助于更有效地 苜蓿害虫的防治

Indirect interactions among organisms are emerging as widespread, important factors in many ecological communities. This research tests the general hypothesis that phytophagous insects interact indirectly through strong effects on the spatial dynamics of natural enemy activity. In particular, it assesses whether aphids (typically among the most abundant and widespread of all phytophagous insects in temperate ecosystems) influence spatial variation in the intensity of parasitism of other insects; parasitoids may accumulate in local areas, and increase their longevity and fecundity, by consuming aphid honeydew. Insect communities of alfalfa provide an excellent test system. Field experiments in alfalfa will test for indirect effects of pea aphids on the alfalfa weevil, as mediated by a parasite wasp specific to the weevil, and as influenced by natural enemies of the pea aphid (ladybeetles). Investigating the web of indirect as well as direct interactions in alfalfa insect communities provides opportunity not only to test for processes of general ecological interest, but also to contribute to more effective management of alfalfa insect pests.