Aqueous extracts of jet-black ant Lasius fuliginosusnests for controlling nosemosis, a disease of honeybees caused by fungi of the genus Nosema

AbstractRecent years have witnessed a fall in the numbers of bee colonies worldwide. To a large extent, this is due to diseases affecting honeybees. One such disease is nosemosis, which is caused by fungi from the genus Nosema. The antibiotic fumagallin used to be administered to treat nosemosis, but as it was found capable of being transferred to bee products, this practice has ceased. We therefore focused on natural substances for treating this disease, among them, aqueous extracts of the nest carton produced by the jet-black ant (Lasius fuliginosus). We tested the influence of 0.1% and 1% concentrations of such extracts on the incidence of nosemosis in honeybees. The “birch carton 2” extract turned out to be the most effective inhibitor of this disease. The incidence of nosemosis following the administration of this extract, as manifested by the number of spores, fell ca 18-fold in comparison with the control. Moreover, the “birch carton 2” extract was not found to be toxic towards bees.