Predicting Spatial Patterns of Insect Pest Populations in Agriculture Based on Land-Use, Insect Diet Breadth, and Insect DispersalEPA Grant Number: F07F21015
Title: Predicting Spatial Patterns of Insect Pest Populations in Agriculture Based on Land-Use, Insect Diet Breadth, and Insect Dispersal
Investigators: O'Rourke, Megan
Institution: Cornell University
EPA Project Officer: Just, Theodore J.
Project Period: January 1, 2007 through January 1, 2010
RFA: STAR Graduate Fellowships (2007) RFA Text | Recipients Lists
Research Category: Biology/Life Sciences , Fellowship - Ecology and Evolutionary Biology , Academic Fellowships
The purpose of this research is to understand how land-use patterns may affect the population dynamics of insects in agriculture. There are four main objectives to this research: 1) to understand whether insect populations correlate to land-use variables at local and regional scales; 2) to understand whether land-use patterns affect insect diet breadth; 3) to understand whether land-use patterns affect insect dispersal; 4) to model insect populations based on land-use, diet breadth, and dispersal and to try to match predictions to observed dynamics.
This research focuses on the effects of land-use patterns on three of the most economically important herbivores of field corn--the northern corn rootworm, the western corn rootworm, and the European corn borer--and on one beneficial insect, the pink-spotted lady beetle. The first phase of the research consists of quantifying populations of these insects in different regions of New York where corn is more and less abundant in the landscape. Landscape metrics of sampled fields and county-wide measurements of land-use are being analyzed with GIS software and have shown correlations with insect populations. Additionally, experiments are planned to understand how land-use patterns affect insect diet breadth and insect dispersal, which are key variables affecting population dynamics. Stable isotope analysis will be used to study whether polyphagous insects shift their diets depending on the food resources in the surrounding landscape. Also, population genetic techniques using microsatellite markers will be applied to understand whether insect dispersal rates are reduced in landscapes with low agricultural acreage. Finally, theoretical spatial models will be developed to predict how populations of insects with different diet breadths and dispersal abilities will respond to different land-use patterns. These theoretical predictions will be related to the initial field observations made in upstate New York.
This research will help to answer the question of whether incorporating a greater diversity of crops into the landscape may help to naturally suppress pest populations in agriculture. This knowledge will help to identify regions of the country where insecticide usage may increase or decrease under future land-use scenarios.