First evidence of the effectiveness of a field application of RNAi technology in reducing infestation of the mite Varroa destructor in the western honey bee (Apis mellifera)

BACKGROUND: The mite Varroa destructor is the most serious pest of the western honey bee (Apis mellifera) and a major factor in the global decline of colonies. Traditional control methods, such as chemical pesticides, although quick and temporarily effective, leave residues in hive products, harming bees and operators' health, while promoting pathogen resistance and spread. As a sustainable alternative, RNA interference (RNAi) technology has shown great potential for honey bee pest control in laboratory assays, but evidence of effectiveness in the field has been lacking. METHODS: We investigated the efficacy and feasibility of a RNAi treatment to improve bee health under natural beekeeping conditions by integrating a honey bee diet with a mixture of dsRNA targeting V. destructor acetyl-CoA carboxylase, Na+/K+ ATPase and endochitinase genes. RESULTS: In treated hives, we observed that the average infestation rate of phoretic Varroa mite was reduced by 33% and 42% relative to control bee...