Minimizing Otiorhynchus Root Weevil Impact in Conifer Nurseries : Insects Affecting Reforestation. Biology and Damage

1989

S. 71-79

40 Lit. Ang.

Unselbständiges Werk

200069374

Black pine weevil (Otiorhynchus sulcatus (F.)) and strawberry root weevil (O. ovatus (L.)) are the most ubiquitous and damaging species in the genus. Larvae of these flightless, parthenogenetic species destroy roots; adults may cause unacceptable defoliation during 4 weeks of maturation feeding and a 3- month oviposition period. They are both generally distributed in much of Europe and North America and in parts of Australia, New Zealand, and Japan where they are occasional pests of conifers in nursery production. Although some insecticides have shown promise for controlling larvae in field plantations of nursery crops, a control strategy based on vigilance for adult activity and thorough-coverage, foliar sprays of effective insecticides is suggested as the main line of chemical defense. Parasitic fungi and nematodes, although effective against root weevil larvae in containerized plants and in greenhouses, are not effective under field conditions.