Levels of parasitism by ichneumonid wasps in various oilseed rape pests in eastern Austria

摘要

In Austria, organic oilseed rape production is limited mainly because of the pest pressure of rape stem weevil (RSW) (Ceutorhynchus napi), cabbage stem weevil (CSW) (Ceutorhynchus pallidactylus) and pollen beetle (Meligethes aeneus). Since in organicproduction of oilseed rape no chemical control is available, biological control strategies are needed. To obtain basic information on parasitoid antagonists, parasitization rates of RSW, CSW and pollen beetle by larval parasitoids (Ichneumonidae: Tersilochinae) were evaluated in winter rape fields in several localities in eastern Austria.