Influence of Colony State, Genetic Background, and Larval Origin on Queen Cell Acceptance and Royal Jelly Yield in Apis mellifera

Commercial queen rearing and royal jelly production represent economically significant sectors of modern apiculture, yet the interactive effects of colony state, genetic lineage, and larval provenance on these processes remain incompletely characterized. This study evaluated the individual and synergistic influences of colony state (queenless vs. queenright), subspecies hybrid (Italian A. m. ligustica vs. Carniolan A. m. carnica), and grafted larval origin on queen cell acceptance rates and royal jelly production efficiency. Young worker larvae (<24 h post-eclosion) from both genetic backgrounds were grafted into artificial queen cups and introduced into standardized cell-builder colonies during peak nectar flow. Results demonstrated that colony state exerted the most significant influence on acceptance rates, with queenless colonies achieved 61.8% acceptance rate compared to 58.5% in queenright colonies (P<0.05). Italian hybrid colonies exhibited superior acceptance rates (64.0%) compared to that of Carniolan hybrids (56.3%, P<0.05), while larval origin showed no significant effect on initial acceptance (P>0.05), suggesting minimal genetic discrimination by nurse bees during early queen cell provisioning. Royal jelly yield per accepted cell was significantly higher in queenless colonies (150.1 mg) versus queenright colonies (143.7 mg, P<0.05), whereas neither colony hybrid nor larval origin significantly affected royal jelly production (P>0.05). These findings indicate that colony state and genetic background of nurse bee populations are primary determinants of queen rearing efficiency and royal jelly productivity, whereas larval genetic provenance plays a negligible role. The results have practical implications for optimizing commercial queen production and royal jelly harvesting protocols.