Toxicidade de produtos fitossanitários utilizados em citros para Apis mellifera

Abstract

The aim of this research was to evaluate the toxicity of several acaricides/insecticides used in Brazilian citrus crop to africanized workers of Apis mellifera Linnaeus. The exposition of honey bees to the chemicals was performed by direct spraying, contamination of food, and contact in treated surface (citrus leaves and Petri dishes), using recommended rates of application. The assays were carried out at 25±2°C, RH 70±10%, 12h of photophase and the data was statistically analyzed, with mean values of mortality being compared through cluster analysis. In all assays acephate was highly toxic, with mortality at 24 hours around 90.0%. When spirodiclofen and pyriproxyfen, was sprayed directly into the honeybees, they caused mortality levels of 11.0 and 15.0%, respectively; buprofezin, sulphur and tetradifon were less toxic, with mean mortality of 5.0% among these compounds. For the assays from contamination surface (citrus leaves and Petri dishes) and food, two groups of chemicals with the same toxic effects were observed, one with acephate and other with buprofezin, sulphur, spirodiclofen, pyriproxyfen, tetradifon and water. The average mortality after 96 hours of exposition was 31.0; 8.3 and 15.7%, respectively, for each method of contamination.