CHEMICAL FACTORS INVOLVED IN SELECTION OF HOST-PLANT FOR OVIPOSITION BY THE PICKLEWORM MOTH (LEPIDOPTERA, PYRALIDAE)

Studies with caged gravid females of the pickleworm, [Diaphania nitida lis (Stoll.)], revealed that leaves of yellow squash (Curcurbita pepo L.) contain small (MW <1000), non-volatile and highly polar amphoteric compounds which stimulate oviposition on artificial sites. Several co mpounds, extracted from paper chromatograms, caused moderate stimulati on of oviposition. When these extracts were recombined, the mixture pr oved highly active. Addition of whole leaf volatiles to the active wat er-soluble fraction increased oviposition. The whole leaf volatiles mi xture could be substituted with volatiles originating from leaf glandu lar trichomes.