Insect Ecology at Purdue - Ian Kaplan's Lab

Sustainable Ag

While all of our research is relevant to sustainable agriculture, several ongoing lab projects are unified by their specific contributions under this broad umbrella. This work tends to be driven by its immediate application potential or implications, as opposed to long-term fundamental research in agroecosystem management. Recent lab efforts in this area focused on the ecosystem services provided by cover crops in organic vegetable systems; namely, weed seed predation by a guild of granivorous beetles and rodents. This research emphasizes biocontrol of post-dispersal weed seeds, and the ecological factors (e.g., intraguild predation between vertebrates/invertebrates, phase of the moon) that mediate flux to the seedbank.

fluorescent powder on mouse

Figure 1. Using fluorescent powder to track mice through a cover crop matrix.

In addition, we are currently studying techniques to establish and maintain beneficial insects in high tunnels for pest biocontrol. High tunnels are analogous to a simple greenhouse; however, unlike greenhouses, they do not provide supplemental lighting or regulate temperature with an automated heating/cooling system. High tunnels, thus, represent a hybrid growth environment with features characteristic of both greenhouse and field settings, but virtually nothing is known about insect management in this unique environment. We have been testing various methods for retaining mass-released predators (e.g., ladybugs, lacewings, Orius) used in augmentation to control aphids and caterpillars. In addition to biocontrol, we are studying the utility of grafting as a tool for enhancing resistance to both soil pathogens belowground and insect pests aboveground.

tunnel

Figure 2. Because they allow farmers to generate a crop far earlier in the spring and extend production late into the fall compared with open-field cultivation, high tunnel popularity among fruit and vegetable growers is on the rise worldwide, particularly in the U.S. where adoption has been more recent.

Last, we are investigating the non-target effects of insecticides on native insect communities. This research focuses primarily on the herbivorous insect fauna associated with milkweed (Asclepias sp.), which commonly grows in close proximity to agricultural fields in the Midwest.