Responses of Diabrotica speciosa and Cerotoma arcuata tingomariana (Coleoptera : Chrysomelidae) to volatile attractants

The relative responses of Diabrotica speciosa (Ger.) and Cerotoma arcuata t ingo-mariana Bechyne (Coleoptera: Chrysomelidae) to traps baited with chemi cals were studied. Volatile substances of Curcubita maxima Duchesne blossom s, other previously reported volatile attractants for Diabroticites and mix tures of chemicals were tested in common bean, Phaseolus vulgaris L., and s oybean, Glycine max (L.) Mer., fields. Traps baited with 1,4-dimethoxybenze ne caught 29.4 times more beetles than solvent controls in fields of soybea ns, and 9.4 times more in common bean fields. Traps baited with VIP (veratr ole + indole + phenylacetaldehyde) caught 6.5 times more beetles than solve nt controls in soybean and 3.5 times more in common bean plots, whereas tra ps baited with TIC (1,2,4-trimethoxybenzene + indole + trans-cinnamaldehyde ) caught 6.7 times more beetles in soybean and 3.5 times more in common bea n plots. Volatile chemicals used in this study did not attract C. a. tingom ariana. In a dose-response study, captures of D. speciosa increased signifi cantly with increasing doses of 1,4-dimethoxybenzene.