When a pesticide is applied in a vineyard, the fraction can drift away from the target and affect the abundance of beneficial arthropods in adjacent crops or hedgerows. A field experiment was conducted in north-eastern Italy using an air-assisted sprayer in order to evaluate the spatial distribution of etofenprox drift in a vineyard-hedgerow system and its effect on the predatory mite Kampimodromus aberrans. Three scenarios of decreasing potential drift were compared, all in still wind conditions. In the worst case of free expansion of drift, 12% of the applied rate drifted for 6-7 m with minor effect on K. aberrans abundance, according to the dose-response assay results; the presence of a hedgerow reduced the drift by about 80%. The hedgerow was also effective when good agronomic practices were followed, and the effect of drift on K. aberrans was not significant, its abundance being mainly linked to the patchiness of the natural population. Because of lateral drift, i.e. not in the direction of air-flow from sprayer, spray was detected at very low concentration in the contiguous untreated vineyard. This had no effect on K. aberrans but had the capacity to contaminate organic crops and provide a risk to surface water and bystanders. This suggests that an environmental regulatory scheme taking hedgerows into account should be supported and implemented on a catchment or regional scale.
Insecticide drift and its effect on Kampimodromus aberrans (Oudemans) in an Italian vineyard-hedgerow system
Otto S;
2013
Abstract
When a pesticide is applied in a vineyard, the fraction can drift away from the target and affect the abundance of beneficial arthropods in adjacent crops or hedgerows. A field experiment was conducted in north-eastern Italy using an air-assisted sprayer in order to evaluate the spatial distribution of etofenprox drift in a vineyard-hedgerow system and its effect on the predatory mite Kampimodromus aberrans. Three scenarios of decreasing potential drift were compared, all in still wind conditions. In the worst case of free expansion of drift, 12% of the applied rate drifted for 6-7 m with minor effect on K. aberrans abundance, according to the dose-response assay results; the presence of a hedgerow reduced the drift by about 80%. The hedgerow was also effective when good agronomic practices were followed, and the effect of drift on K. aberrans was not significant, its abundance being mainly linked to the patchiness of the natural population. Because of lateral drift, i.e. not in the direction of air-flow from sprayer, spray was detected at very low concentration in the contiguous untreated vineyard. This had no effect on K. aberrans but had the capacity to contaminate organic crops and provide a risk to surface water and bystanders. This suggests that an environmental regulatory scheme taking hedgerows into account should be supported and implemented on a catchment or regional scale.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
