The Carniolan honey bee, Apis mellifera carnica, is Slovenian autochthonous breed. In recent years, Slovenia, similarly to the rest of the Europe, recorded 15-35% annual loss of bee colonies due to mortality of bees. One of the possible reasons for this could be the exposure of bees to residues of insecticides, acaricides, herbicides and fungicides, which have been found in honeybees and hive products. Acaricides are applied by beekeepers to control ectoparasitic mite Varroa destructor, the most serious pest of honeybee colonies in Europe, whereas the most abundant and common agricultural chemicals found in honeybee are fungicides, which may enter the bee and hive products when applied to nearby flowering crop and fruit plants. Acaricides and fungicides are not highly toxic to bees alone, but they may act in combination and lead to higher honeybee mortality. In our study we investigated the molecular response of different development stages of honeybee workers (larvae, pupae, adult) exposed to a combination of acaricide kumaphos and fungicide procloraz per os. We examined the expression of several genes involved in immune response, detoxification and development by quantitative RT-PCR. We observed that combination of acaricide and fungicide leads to a synergistic effect on several of the immunity-related, detoxifying and development genes. We also found that the kumaphos and procloraz, solitarily or in combination, have important impact on gene expression and that the impact is different in different development stages of honeybee worker.
COBISS.SI-ID: 3453576