Seletividade de óleos essenciais de menta e alfavaca a Apis mellifera L. (Hymenoptera: Apidae)

Abstract

Apis mellifera Linnaeus, Linnaeus, 1758 (Hymenoptera: Apidae) honeybees are social insects, considered useful because of their importance to ecosystems. They are responsible for 80% of the pollination of cultivated plant species in the world and they are honey, propolis, royal jelly, wax and apitoxin producers. However, they are suffering from the disappearanceand, among the suspects, stand out the synthetic chemical insecticides. As an alternative, there is the alternative control of pests, however, the researches of effects of essential oils on bees are still scarce. The objective of this work was to evaluate the selectivity of essential oils (OEs) Mentha arvensis(mint), Ocimum gratissimum (basil-harpsichord) e Ocimum selloi(basil-anise) at 1% onA. melliferaworkers. For this, in the laboratory, two bioassays wereperformed: 1) Bioassay of contact of A. melliferaon treated surface: the solutions of OEs were sprayed in petri dishes, later, groups of 10 bees were placed on the plates, where they remained for 2 hours, being subsequently transferred to PVC cages, with candy and cotton soaked in water; 2) Bioassay of ingestion, the bees were anesthetizedand transferred to the cages, where they received Candi paste incorporated with the treatments. Both bioassays were kept in climatizedroom (27 ± 2° C, R.H. 60 ± 10%, photophase 12h). The workers’ survivalfrom one to 240 hours was evaluated. The essential oil of O. selloi (basil-anise) reduced the survival of the workers of A. mellifera, in the concentration of 1%, when ingested. The oil of O. gratissimum (clove lavender) reduced the survival of the workers, when they came into contact, at a concentration of 1%, in the laboratory. The essential oil of M. arvensis (mint) was considered selective, as it did not interfere in the survival of workers of A. mellifera.