Environmental stress assessment in genetically related honey bee foragers (Apis mellifera) kept in urban and rural conditions

Urban beekeeping is common and has become a permanent part of the landscape of many cities. However, there is scarce information about the health of honey bees (Apis mellifera) from apiaries in cities. Here, we present that the living environment of bees from urban apiaries is not indifferent to their total antioxidant capacity, immune system (defensin-2), and proteostasis (Hsp70). Still, the city does not always have only negative effects. Using an experimental system of genetically related bee colonies located in urban and rural environments, we found that genetic factors, environmental factors, or both impact the levels of the analyzed stress biomarkers. The response to environmental stress in the urban and rural areas was tissue-dependent and changed during the season. Our results will be valuable in discussing bee welfare in cities.