Publications by authors named "Robert N. Wiedenmann"

Agricultural dependency on insect-mediated pollination is increasing at the same time that pollinator populations are experiencing declines in diversity and abundance. Current pollinator research in agriculture focuses largely on diurnal pollinators, yet the evidence for pollination by moths and other nocturnal pollinators is growing. Apples are one of the most valuable and important fruits produced globally, and apple production is dependent on insect-mediated cross-pollination to generate a profitable crop.

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We evaluated the potential for competition between the exotic ichneumonid parasitoid Pimpla disparis Vierick and the native ichneumonid Itoplectis conquisitor Say, in the form of multiparasitism and destructive host feeding, by examining how previous oviposition experience influenced host selection. Both species commonly attack the host species, bagworm, Thyridopteryx ephemeraeformis (Haworth) (Lepidoptera: Psychidae), in central Illinois. We used in our study adult female parasitoids that were naïve, had previously oviposited into hosts that contained heterospecifics, or had oviposited into hosts that initially were unparasitized.

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Male Galerucella calmariensis and Galerucella pusilla (Coleoptera: Chrysomelidae) emit an aggregation pheromone while feeding on host foliage. Isolation of the compound from collected volatiles was guided by comparisons of gas chromatograms of extracts from males and females and by gas chromatography-electroantennographic detection. The compound was identified by a combination of spectrometric methods and microchemical tests as the novel dimethylfuran lactone, 12,13-dimethyl-5,14-dioxabicyclo[9.

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In this study, we measured the effects of three commonly used insecticides classified as insect growth regulators, on the encyrtid parasitoid Leptomastix dactylopii (Howard) when parasitizing citrus mealybug, Planococcus citri (Risso). Kinoprene, pyriproxyfen, and azadirachtin were evaluated in both petri dish and a cage experiment at label-recommended rates to measure their effects on the mortality, parasitization rate, and sex ratio of L. dactylopii.

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The nutritional suitability of corn pollen for the facultatively phytophagous predator Coleomegilla maculata was studied in the laboratory. Dry matter, organic matter, ash, crude protein, amino acid, and quercetin contents of pollen from 10 hybrids of field corn were determined. C.

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We studied the development of teratocytes derived from two congeneric gregarious endoparasitic species, Cotesia chilonis and C. flavipes, parasitizing two congeneric novel hosts, Diatraea saccharalis and D. grandiosella.

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