INSECT LARVAE CONTAIN SUBSTANCES TOXIC TO ADULTS - THE DISCOVERY OF PARALYSINS

Acidic methanolic extracts of larvae of nine different insect species were found to contain substances that cause a lethal effect in the adu lt stage of the same species and of other species. These endogenous to xic substances, apparently being widely spread over the class of insec ts, were designated as paralysins, because of their immediate and obse rvable paralytic effect upon injection. The developmental concentratio n curves of five different species of insects (Galleria mellonella (Le pidoptera), Neobellieria bullata (Diptera), Spodoptera frugiperda (Lep idoptera), Tenebrio molitor (Coleoptera) and Schistocerca gregaria (Or thoptera) indicate that the toxins are not present throughout all the developmental stages in the same concentration. The strongest paralyti c activity was found in late instar larvae or in the early pupal stage . The temporal distribution of paralysins during development suggests that they might be involved in metamorphosis. (C) 1998 Elsevier Scienc e Ltd. All rights reserved.