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(19-14) Effects of lambda-cyhalothrin on Poecilus cupreus in wheat and an adjacent grass strip. Baier, Barbara*,1, Schenke, Detlef1, Heimbach, Udo2, 1 Federal Biological Research Centre for Agriculture and Forestry, Kleinmachnow, Germany2 Federal Biological Research Centre for Agriculture and Forestry, Braunschweig, Germany ABSTRACT- From 1998 to 2000, a field study was carried out to determine the effects of a KARATE WG™ application (7,5 g a.i./ha) in a wheat field on non-target arthropods in the adjacent grass strip by spray drift. Semi-field tests for evaluating the effects and exposure of lambda-cyhalothrin on Poecilus cupreus adults were part of the investigations. For that purpose, metal frames were sunk into the soil of the wheat field and in the grass strip at a distance of 1 m from the field boundary. Adult Poecilus cupreus, reared in laboratory, were released 30 minutes before application. Mortality and behavioural changes were studied on the soil surface without destroying the soil structure in the frames 1, 2, 3, 7, 10 and 14 days after application. Finally, the whole soil of the frames was checked for dead and living beetles. On all days, the number of Poecilus cupreus seen on the soil surface in the grass strip was very small compared to the number seen in the wheat field, both in the exposed plots and in the untreated controls. Clear effects were observed in the treated field, but the application of KARATE WG™ had no effect on Poecilus cupreus in the grass strip. Simultaneously, carabids were removed from the soil in the frames in the field and grass strip one day after application for the purpose of determining exposure. A second sample was taken only in the field, after two or three days. The concentration of lambda-cyhalothrin in Poecilus cupreus adults was determined after preparation and analysis, using GC-MS2/NCI. Measured residues in the arthropods are correlated with spray drift measured using colour tracer on artificial collectors, the calculated basic drift values and residues of lambda-cyhalothrin in the habitat of carabids. Key words: spray drift, Poecilus cupreus, lambda-cyhalothrin |
