Publications by authors named "Loke T Kok"

Daily distributions of eclosion and mating activities of Pseudopidorus fasciata Walker (Lepidoptera: Zygaenidae) were recorded under natural and various laboratory conditions. Eclosion of this insect exhibited circadian gating in constant darkness (DD) but not in constant light (LL) at 28°C. Under natural conditions, the majority of adults emerged in midmorning with an eclosion peak around 1000 hours.

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Eastern hemlocks (Tsuga canadensis Carrière) at two sites in southwestern Virginia were treated by trunk and soil injections of imidacloprid to determine the insecticide's impact on hemlock woolly adelgid, Adelges tsugae Annand. Treatments were 25, 50, and 100% of the highest labeled dosage rates for both stem and soil injection. Three and 4 yr after treatment, the half and full rates had significantly reduced A.

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Eastern hemlock, Tsuga canadensis (L.) Carrière, branchlets were systemically treated with imidacloprid and bioassayed with hemlock woolly adelgid, Adelges tsugae (Annand) (Hemiptera: Adelgidae), and predators. After 10 d, two hemlock woolly adelgid predators, Laricobius nigrinus Fender (Coleoptera: Derodontidae) and Sasajiscymnus tsugae Sasaji & McClure (Coleoptera: Coccinellidae), were allowed to feed on remaining hemlock woolly adelgid for 20 d on branches systemically treated with 1, 10, or 100 ppm imidacloprid.

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Background: Imidacloprid is the primary insecticide used against the exotic invasive insect hemlock woolly adelgid, Adelges tsugae Annand, a pest of eastern hemlock [Tsuga canadensis (L.) Carrière] trees in the eastern United States. A competitive enzyme-linked immunosorbent assay (ELISA) was evaluated for quantification of imidacloprid in eastern hemlock wood and needle tissues.

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