Biology of Niesthrea louisianica (Hemiptera: Rhopalidae) on Selected Plants, and its Potential for Biocontrol of Velvetleaf, Abutilon theophrasti (Malvaceae)

Abstract

Large populations of Niesthrea louisianica Sailer affect the reproduction of velvetleaf, Abutilon theophrasti Medicus, a malvaceous weed found in cotton and soybean fields in west-central Mississippi. Development of the bug to adult was fastest in the laboratory on fresh fruiting structures of this plant, and of rose-of-Sharon, Hibiscus syriacus L., and prickly sida, Sida spinosa L. Development on okra, Ebelmoschus esculentus (L.) Moench, was slower, and was not completed on bolls of cotton, Gossypium hirsutum L. Some development to adult occurred on water-soaked cotton seeds, but nymphal mortality and development time were greater than on water-soaked velvetleaf seeds. Nymphs could not complete development on velvetleaf seedlings or on damp or dry okra seeds. Water-soaked velvetleaf seeds were satisfactory for laboratory rearing of these insects. Greenhouse tests demonstrated that third instars significantly reduce production of velvetleaf buds, blooms, and fruits when caged over terminal flower buds for 2 weeks. Fifth instars caged over single half-grown fruits for 2 weeks caused fruit abortion. Seed germination was reduced 95 to 99% when nymphs were caged over full-size green fruits. A Telenomus sp. was reared from egg masses from velvetleaf and rose-of-Sharon. Leucostoma simplex (Fallén) was reared from adults, and two spider species were observed feeding on nymphs and adults in the field.