Pathogenicity of aerobic bacteria isolated from honeybees (Apis mellifera) in Ordu Province

Abstract

The honeybee (Apis mellifera) is an important pollinator insect. Any pathogenic infection in this beneficial insect is undesirable. In this study, bacterial diversity in beehives was investigated to determine the potential of pathogenic bacteria in honeybees. To do this, bacterial isolations were carried out from dead and diseased adult bees collected from 9 districts in Ordu Province in Turkey. Twenty species of pathogenic bacteria, 18 of which were nonsporeforming Staphylococcus lentus, Klebsiella oxytoca, Citrobacter freundii, Leucanostoc mesenteroides ssp. cremoris, Kocuria rosea, Kocuria kristinae, Sphingomonas paucimobilis slashline, Burkholderia cepacia, Leucanostoc mesenteroides ssp. dextranicum,Hafnia alvei, Escherichia coli, Aeromonas salmonicida, Citrobacter braakii, Pantoea agglomerans, Streptococcus equi ssp. zooepidemicus, Staphylococcus pseudintermedius, Staphylococcus lugdunesis and Staphylococcus vitulinus and 2 sporeforming Bacillus licheniformis and Paenibacillus polymyxa, were isolated and identified from the honeybees. The infectivity of these bacteria were also documented with bioassay experiments on the healthy bees. The highest insecticidal effect was determined with Bacillus licheniformis (84%), Escherichia coli (84%), and Streptococcus equi ssp. zooepidemicus (80%) on the adult honeybees. This result confirms that the honeybee contains a very large number of bacterial species and that the majority of them are pathogenic for the species in Turkey. In addition, some of the entomopathogenic bacteria used for biological control can have negative impact on this economically important insect.