|Panizzi, A - EMBRAPA, BRAZIL|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: September 10, 2004
Publication Date: September 10, 2004
Citation: Panizzi, A.R., Berhow, M.A., Bartelt, R.J. 2004. Oviposition of the southern green stink bug, Nezara viridula (L.) on artificial substrates conditioned by chemical extracts from soybean plants [abstract]. XX Brazilian Congress of Entomology, Program and Abstracts. p. 104. Technical Abstract: A laboratory bioassay was developed for testing oviposition preference of the southern green stink bug, Nezara viridula (L.) (Heteroptera: Pentatomidae) toward chemicals extracted from soybean pods and leaves. In this bioassay, an artificial substrate (cheesecloth) was stretched over a wooden ring (embroidery hoops), treated with plant extracts or chromatographic fractions, and then exposed to adult stink bugs to assess oviposition preference. The methanol extract of pods stimulated the greatest oviposition. After a chromatographic separation on a reverse phase open column, the most active fraction derived from this extract was that eluted with 20% methanol in water. After subjecting this fraction to chromatography on silica, the greatest activity occurred in the fraction eluted with 60% methanol in methylene chloride. Further fractionation of this material by TLC gave no single fraction with demonstrated activity, but the recombined fractions were again active, indicating that multiple components are likely involved in eliciting oviposition. Antennectomized females did not differentiate treated vs. untreated substrates, but females with the hairs of the genitalia coated did, indicating that the oviposition-eliciting compounds were sensed by the antennae, rather than by hairs of the genital plaques.