Wirkung verschiedener Insektizide und Repellentien gegen den Gemeinen Birnenblattsauger (Cacopsylla pyri)

Summary

The efficacy of different insecticides (neem, pyrethrin, spinosad, and rotenone) and a repellent (kaolin) applied with different strategies (single or repeated applications) against the over-wintering pear suckers (Cacopsylla pyri) and nymphs of the first generation was tested in a field trial in Switzerland in spring 2003. Rotenone, the only admitted product in Swiss organic agriculture, showed good effects. But, since Rotenone is toxic for non-target insects we looked for an alternative. The application of spinosad (Audienz) in combination with rape oil (Telmion) as well as the application of pyrethrum showed similar efficacy as rotenone. Neem had no or a very low impact on the pear sucker populations. The repellent kaolin (Surround® WP) showed the best efficacy against the European pear sucker: triple application of kaolin before blossom was most efficient. Since kaolin is not toxic for beneficials this product might be an alternative to rotenone.