Managing a crop pest means more than simply spraying fields with insecticides. What and when to spray, how much, and where to apply chemicals are all questions that any successful pest control must address. To further complicate things, the answers to those questions will change with any given pest. How then do we confront the vast number of pests plaguing our agricultural systems? Dr. Jim Miller believes he has an answer, and it begins with sex.
Since the discovery and identification of insect sex pheromones in the late 1960’s, researchers quickly saw the benefits of deploying these chemicals in our agricultural systems. They act as lures and can be a powerful tool to survey the pest population a given area. Dr. Miller’s work provides a framework connecting the number of insects caught in a trap to the number of pests posing a hazard to a crop.
To investigate this problem, Dr. Miller first turned to computer simulations. He hypothesized that if we could model the behavior of a pest prior to it detecting a pheromone plume, we could estimate the chances the insect will end up in a trap, thus would more accurately calculate the number of pests per acre using count data from pheromone traps. Observational studies previously performed by Dr. Miller have shown that the codling moth, Cydia pomonella, moves randomly from one direction to the next in the absence of an attractant. However, because the number of such choices a moth can make are limited, the outcome follows a common mathematical distribution called a standard bell curve. Armed with probabilities of directional choice, Dr. Miller executed a series of computer simulations and generated equations predicting codling moth behavior at various infestation levels. The next step was to head to the field and put these equations to the test.
Though Dr. Miller is considering retirement, he knows the importance of his findings and believes others will certainly take up the reigns. Still, after his recent work, he has gone on to improve the methods for trapping pests in pheromone-baited traps and his model for calculating absolute density has been successful with several additional crop pests including japanese beetles, spotted wing drosophila, pine sawfly and the sweet potato weevil. Keep an eye out for results from his current research investing the application of this work for control of the gypsy moth, Lymantria dispar!
Anthony Nearman is graduate student studying under Dr. Dennis vanEngelsdorp. He is currently using epidemiological data to drive research into the pathophysiology of honey bee diseases.
Veronica Yurchak is a first year PhD student studying under Dr. Cerruti Hooks. Her research will focus on further identifying sustainable weed and insect control methods in sweet corn production.