TOLERANCE OF WESTERN CORN-ROOTWORM LARVAE (COLEOPTERA, CHRYSOMELIDAE)TO 6-METHOXY-2-BENZOXAZOLINONE, A CORN SEMIOCHEMICAL FOR LARVAL HOST LOCATION

6-Methoxy-2-benzoxazolinone (MBOA) and 2,4-dihydroxy-7-methoxy-1,4-ben zoxazin-3-one (DIMBOA), its natural precursor, are toxic to many insec t species. We studied the possible toxicity of MBOA, a host-location s emiochemical for western corn rootworm larvae, to larvae of this speci es. DIMBOA previously was shown by other workers to be toxic to first- instar western corn rootworm, Diabrotica virgifera virgifera LeConte. Using methods that previously showed DIMBOA to be toxic, we found that MBOA had no toxic effects on larvae of the western com rootworm. The tolerance of western corn rootworm larvae to MBOA is consistent with t he putative role of this benzoxazolinone as a semiochemical for the sp ecies.