Experimental improvement of honey bee (Apis mellifera) queen quality through nutritional and hormonal supplementation

Queen reproductive potential (=quality) impacts the health and productivity of honey bee colonies. To determine the factors that affect reproductive quality during development, we tested queens produced under larval treatments by supplementing the diet with juvenile hormone (JH), additional sugars, or both, compared to untreated control. Furthermore, we varied the age of the larvae that were grafted (1 and 3days old). We analyzed newly emerged virgin queens for their morphological characters as proxies for their reproductive potential. We found that the application of a sugar-enriched diet in combination with JH application onto 1st instar queen larvae produced higher-quality queens, while for 3rd instar larvae only the JH treatment resulted in increasing queen quality. For mated queens, those treated with JH plus supplemented sugars showed a significantly higher sperm count and sperm viability. Our findings demonstrate that honey bee queen reproductive potential can be increased through diet supplementation.