Environmental Entomology (1983) 12, 848-851

Robert P. Doss (1983)
Activity of obscure root weevil, Sciopithes obscurus (Coleoptera: Curculionidae), phagostimulants individually and in combination
Environmental Entomology 12 (3), 848-851
Abstract: Obscure root weevil, Sciopithes obscurus Horn, phagostimulants, previously identified as components of extracts from Rhododendron leaves, were tested individually and in combination by using a membrane filter disc bioassay procedure. When sucrose and sitosterol were applied individually, a plateau in feeding was reached at the concentration found in Rhododendron leaves (area basis). Application of higher levels did not lead to significantly more feeding. With quercetin-3-galactoside, feeding was greatest on discs treated with a concentration comparable to that of Rhododendron leaves. There was less feeding with higher and lower levels. Weevils fed much more on filter discs bearing any two phagostimulants than on discs bearing only one phagostimulant. Discs treated with all three phagostimulants, at concentrations equivalent to those in Rhododendron leaves, were fed on more than were discs bearing only two phagostimulants.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)

Research topic(s) for pests/diseases/weeds:
general biology - morphology - evolution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Sciopithes obscurus	Rhododendron (crop)	U.S.A. (NW)