ATTRACTANCY OF VOLATILE NON-PHEROMONAL SEMICOCHEMICALS TO NORTHERN CORN-ROOTWORM BEETLES (COLEOPTERA, CHRYSOMELIDAE) IN EASTERN SOUTH-DAKOTA

Studies were conducted in maize fields in eastern South Dakota in 1990 and 1992 to compare the attractiveness of several volatile, non-phero monal semiochemicals to adult northern corn rootworms (Diabrotica barb eri Smith and Lawrence). In 1990, during the late stages of maize deve lopment, eugenol and cinnamyl alcohol increased the capture of males r elative to unbaited traps. Captures of females were greatest on traps baited with eugenol or cinnamyl alcohol; trans-cinnamaldehyde and 4-me thoxyphenethanol also increased female capture relative to unbaited tr aps. In 1992, sticky traps baited with eugenol or cinnamyl alcohol cap tured more beetles than those baited with 4-methoxyphenethanol, except during silking, when no compound significantly attracted males and th e capture of females averaged less than 1 beetle/trap. 4-Methoxyphenet hanol did significantly increase catch relative to unbaited traps unti l the late stages of maize development. These results contrast with pr evious evidence that 4-methoxyphenethanol is a superior attractant for D. barberi, and suggest that there may be regional differences in the relative attractiveness of volatile non-pheromonal compounds to D. ba rberi.