University of California

Sampling program for grape mealybugs improves pest management


Chris A. Geiger
Kent M. Daane
Walter J. Bentley
Glenn Y. Yokota
Lee A. Martin

Authors Affiliations

C.A. Geiger is Associate Environmental Research Scientist, California Department of Pesticide Regulation (CDPR) and was Postdoctoral Researcher, Center for Biological Control, Division of Insect Biology, UC Berkeley; K.M. Daane is Extension Specialist, Center for Biological Control, UC Berkeley; W.J. Bentley is Integrated Pest Management (IPM) Entomologist, UC Kearney Agricultural Center; G.Y. Yokota is Research Associate, Center for Biological Control, UC Berkeley; L.A. Martin is Lab Assistant, UC IPM Program.

Publication Information

Hilgardia 55(3):19-27. DOI:10.3733/ca.v055n03p19. May 2001.

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The results of a mealybug study in Central Valley vineyards, designed to develop sampling guidelines, reveal that mealybug distribution on vines varies greatly through the season and that mealybugs usually prefer concealed locations, such as under bark. This combination makes sampling difficult. A number of sampling techniques were compared. Three- or 5-minute timed counts were most efficient because samplers could follow the mealybugs' movement over the season. Midseason counts were much better predictors of damage at harvest than early season counts. This research confirms past control guidelines and opens new control options. Grape bunches touching vine trunks or spurs will have higher damage. Removing these bunches or using barriers between bunches and mealybug oviposition sites can also reduce damage.


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Geiger C, Daane K, Bentley W, Yokota G, Martin L. 2001. Sampling program for grape mealybugs improves pest management. Hilgardia 55(3):19-27. DOI:10.3733/ca.v055n03p19
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