Ecotoxicology of several acaricides used in apple orchards to the honeybee, Apis mellifera : from the laboratory to the field study

다국어 초록 (Multilingual Abstract)

Pollination is an important factor in apple production. Improper pesticide use can endanger pollinators including honeybee populations, subsequently resulting in losses of apple yield. In this study, we evaluated the effects of acaricides on the honeybee, Apis mellifera L. in the laboratory and field against 12 synthetic acaricides which are broadly employed in apple production against the two-spotted spider mite and European red mites. In the laboratory, the contact and feeding toxicity results demonstrated that the four acaricides were hazardous and the others evidenced low toxicities at their recommended concen-trations. In the field studies, we selected and tested the four most toxic of theacaricides: acequinocyl, amitraz, fenthion, and phosphamidon. Most of the acaricides caused 100% mortality within 24hr of direct spraying in the field, except for acequinocyl (36%). The effects of fumigation were found to exhibit 100% mortality for fenthion and phosphamidon 1hr after treatment (HAT). At 24 HAT, the fumigation effect was reduced to less than 50% mortality, respectively. At 48 HAT, honeybee mortalities from fumigation were lower than 10%, with the exception of phosphamidon (25%). Based on the results of this study, even for highly toxic acaricides, if honeybees are exposed 24 or 48 hr after treatment, honeybee mortality would be drastically reduced.