Professor of Entomology Cornell University Geneva, New York
The maggot complex consisting of Delia antiqua and Delia platura is a major constraint for producing onions across the temperate regions of North America. Species abundance and pest status likely vary among production regions, but a comprehensive survey has not been conducted. Similarly, management of the Delia complex varies dramatically with certain insecticides across regions, but it is not known if these differences are species specific or if populations are resistant to certain insecticides. Our research aims to quantify the abundance of Delia species in onion fields throughout production regions in the northern USA and Canada and to determine which species is primarily responsible for killing onion plants. Additionally, we are interested in assessing the susceptibility of maggot populations to currently used insecticides, especially spinosad and cyromazine. Collectively, results from this study will generate fundamental information about the dominant Delia species in particular production regions and their relative susceptibility to commonly used insecticides.