|Castle Del Conte, Sandra|
Submitted to: Annals of the Entomological Society of America
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/17/2009
Publication Date: 7/1/2010
Publication URL: http://hdl.handle.net/10113/43464
Citation: Wright, L.C., James, D.G., Reyna, V., Castle Del Conte, S., Gingras, S., Landolt, P.J., Brooks, T. 2010. Species Composition of Cutworm Larvae (Lepidoptera: Noctuidae) in South Central Washington Vineyards. Annals of the Entomological Society of America. 103(4):592-596. Interpretive Summary: Cutworms are larvae of moths that can severely damage new spring buds of fruit trees and vines. In the Yakima Valley of Washington, a large number of species of cutworm moths are present in irrigated agricutlure areas, and we do not know which species are capable of causing economic damage to fruits. Researchers at the USDA-ARS laboratory in Wapato, Washington are collaboring with scientists at Washington State University, Prosser, Washington to develop a comprehensive data base on what species of cutworms are feeding on fruit crops. As a part of this study, grape vines and vineyard floors were sampled at night over a 4-year period for caterpillars. Most caterpillars on grape vines were Abagrotis orbis or Agrotis vetusta, while many other species were present in the vineyard but not on the vines. It was thought before this study that most damage was done by spotted cutworm and redbacked cutworm. This is new and surprising information that necessitates a different approach to monitoring and pest management.
Technical Abstract: The major grape growing areas of Washington were surveyed during 2003-2007 to determine the cutworm species present as larvae in vineyards during spring. We sampled vineyard floors, vines at night, and vines during the day. A total of 1,003 larvae was collected and 650 were reared to adults and identified. Twenty-five species were found: 22 on the ground, eight on vines at night, and two on vines during the day. Almost 75% of the cutworms on vines at night were Abagrotis orbis (Grote) and 19% were Agrotis vetusta Walker. The spotted cutworm, Xestia c-nigrum (L.), and the redbacked cutworm, Euxoa ochrogaster (Guenee), previously reported to be the major cutworm pests of grapes in Washington, were rare with only four X. c-nigrum and no E. ochrogaster collected. The abundance, phenology and life histories of cutworm species are discussed with respect to their impact and management in Washington viticulture.