INFLUENCE OF TILLAGE SYSTEM, PLANTING DATE, AND OILSEED CRUCIFERS ON FLEA BEETLE POPULATIONS (COLEOPTERA: CHRYSOMELIDAE)

Abstract

Abstract Cultural practices (tillage, planting date) were examined for their effect on flea beetle, Phyllotreta cruciferae (Goeze), populations in three species of oilseed crucifers— Brassica napus L., B . rapa L., and Crambe abyssinica Hochst. No-till appeared to reduce flea beetle densities when compared with conventional tillage. The greater structural diversity of the no-till plots might be interfering with host plant location. Earlier plantings had significantly more flea beetles per plant than later plantings. The Brassica crops yielded higher densities of beetles compared with crambe, supporting earlier reports of crambe resistance.