Temperature effects on a caterpillar host immune response to parasitism

Species interactions structuring agricultural communities can provide insight into the functioning and stability of the community, and structure can be visualized with interaction networks. An understanding of which species are present in a given area and how they interact over time is imperative for making informed decisions about appropriate integrative pest management strategies that reduce the use of pesticides and increase yield. Parasitoids of lepidopteran agricultural pests can serve as effective biological control agents to reduce crop damage. Host plants often mediate the interaction between herbivores and parasitoids because cultivars can differ in nutritional quality, volatile emission, and other characteristics that can exert strong bottom-up effects. Conversely, parasitoids are known to strongly regulate herbivore populations. Interaction networks can exhibit strong temporal variation due to turnover of species. The objectives of this study were to characterize the multi-trophic network between Brassica host plants, lepidopteran herbivores, and parasitoids, in addition to understanding how the community of herbivores and natural enemies varies across 3 years at an organic farm in VA.