Ted E. Cottrell, Dan L. Horton
Journal of Entomological Science 48 (3), 184-194, (1 July 2013) https://doi.org/10.18474/0749-8004-48.3.184
KEYWORDS: Naupactus, Callirhopalus, Sitona, Sphenophorus, Prunus, root-feeding
Injury to peach, Prunus persicae (L.) Batsch, roots is common by several plant pathogen species and by larvae of the peachtree borer, Synanthedon exitiosa Say (Lepidoptera: Sesiidae). External feeding injury to peach roots was observed that was not consistent with S. exitiosa injury but was suspected to be caused by the larvae of root-feeding weevil species (Coleoptera: Curculionidae). Thus, we used conical emergence traps for 3 yr to sample in unsprayed peach orchards (within the dripline of trees and at missing tree sites) to monitor for root-feeding weevils. Fuller rose beetle, Naupactus cervinus (Boheman), whitefringed beetles, Naupactus spp., and the twobanded Japanese weevil, Callirhopalus bifasciatus (Roelofs), (Coleoptera: Curculionidae) were captured at significantly higher numbers within the dripline of the tree than at missing tree sites. Adult N. cervinus emerged from soil year around; whereas, the other 2 species had seasonal emergence. In commercial peach orchards comprised of cultivars with early, mid, and late-season fruit ripening dates, N. cervinus was more abundant than other species. The later a cultivar ripens, the higher the number of insecticide applications it receives; however, we did not detect a difference in N. cervinus emergence between the cultivars. In another sprayed orchard, N. cervinus was again more common than other curculionid species captured. Damage ratings (0 - 5; none to heavy, respectively) on roots revealed a mean rating of 2.79 ± 0.12. Year-long emergence of N. cervinus is likely why it persisted in sprayed orchards. Modification of existing pest management programs will be needed to manage N. cervinus attacking peach roots.