title: Management of Chinese Rose Beetle (Adoretus sinicus) Adults Feeding on Cacao (Theobroma cacao) Using Insecticides.
abstract: The Chinese rose beetle (Adoretus sinicus Burmeister (Coleoptera: Scarabaeidae)) is an introduced, widely-established pest in Hawai'i. The adult beetles feed on the leaves of cacao (Theobroma cacao L.), which can lead to defoliation and even death of young trees. We evaluated the impact of five commercially available products with different active ingredients (imidacloprid, azadirachtin, Beauveria bassiana (Bals.-Criv.) Vuill., kaolin clay, and pyrethrin) and the presence or absence of weed mat cover in reducing adult beetle feeding on sapling cacao in the field. The use of weed mat cover reduced feeding damage compared to the untreated control, as did foliar application of imidacloprid, azadirachtin, and B. bassiana. In the laboratory, field-collected adult beetles were presented cacao leaf samples dipped in one of the five products and compared to a control. Beetles exposed to pyrethrin died rapidly. Among the other treatments, only exposure to imidacloprid significantly reduced survival relative to the control. Beetles fed very little on leaf samples with azadirachtin but their longevity was not significantly reduced. Imidacloprid, azadirachtin, and weed mat application had the most promise for reducing adult Chinese rose beetle feeding damage in young cacao and deserve further investigation for successful management of this significant pest.
authors.affiliation: Department of Plant and Environmental Protection Sciences, College of Tropical Agriculture and Human Resources, University of Hawai'i Manoa, 3050 Maile Way, Gilmore Hall 310, Honolulu, HI 96822, USA. helen.spafford@hawaii.edu.
authors.forename: Helen
authors.initials: H
authors.lastname: Spafford
authors.affiliation: Department of Plant and Environmental Protection Sciences, College of Tropical Agriculture and Human Resources, University of Hawai'i Manoa, 3050 Maile Way, Gilmore Hall 310, Honolulu, HI 96822, USA. aching2@hawaii.edu.
authors.forename: Alexander
authors.initials: A
authors.lastname: Ching
authors.affiliation: Department of Plant and Environmental Protection Sciences, College of Tropical Agriculture and Human Resources, University of Hawai'i Manoa, 3050 Maile Way, Gilmore Hall 310, Honolulu, HI 96822, USA. manleym@hawaii.edu.
authors.forename: Megan
authors.initials: M
authors.lastname: Manley
authors.affiliation: Department of Plant and Environmental Protection Sciences, College of Tropical Agriculture and Human Resources, University of Hawai'i Manoa, 3050 Maile Way, Gilmore Hall 310, Honolulu, HI 96822, USA. chardin1993@gmail.com.
authors.forename: Chelsea
authors.initials: C
authors.lastname: Hardin
authors.affiliation: Department of Tropical Plant and Soil Sciences, College of Tropical Agriculture and Human Resources, University of Hawai'i Manoa, 3190 Maile Way, St John Hall Room 102, Honolulu, HI 96822, USA. hcbitt@hawaii.edu.
authors.forename: Harry
authors.initials: H
authors.lastname: Bittenbender
keywords: biopesticide; entomopathogen; neem; ornamental; pest management