Investigations on the efficacy of different products for the control of Stephanitis pyri in an organic pear orchard during the two-year period 2004-'05

Summary

The results of two trials, carried out respectively in 2004 and 2005, against Stephanitis pyri in an organic pear orchard are reported. Different formulations of the following active substances were tested: pyrethrum + PPBO, rotenone, rotenone + pyrethrum + PPBO, azadirachtin, Beauveria bassiana strain ATCC 74040, Marsiglia and potassium soap; and quassia wood. The pyrethrum + PPBO- and rotenone-based formulated products showed good efficacy, when applied against neonate larvae. A good efficacy was also observed with the azadirachtin-based formulation, but the product may have phytotoxic effects on pear, and therefore its use is not recommended. The B. bassiana-based product showed partial efficacy in controlling the target pest, while the efficacy of the formulations based on Marsiglia soap, Potassium soap and Quassia wood was not satisfactory.