Beeswax-Based Tools for Queen Rearing Without Grafting Larvae for Apis mellifera

Queen bees form the core of honeybee colonies for reproduction, and their quality is the most critical factor affecting their reproductive and productive performance. In apicultural production, queen rearing requires beekeepers to perform manual larval grafting. This is strongly limited by the beekeepers’ eyesight and technical proficiency and has become a bottleneck restricting the development of modern apiculture. To overcome this long-standing technical challenge, we designed beeswax-based tools for queen rearing without grafting larvae for Apis mellifera. The tools consist of three core components: a single-sided hollow beeswax comb foundation, beeswax larval holders and beeswax queen cells with a hole at the bottom. The holders are paired with the hollows of the beeswax comb foundation and the hole of the beeswax queen cells. Following the construction of the comb by honeybees on the hollow foundation, the queen was confined to lay eggs on the single-sided comb. Subsequently, larval holders containing eggs or larvae were pulled out, assembled with beeswax queen cells, embedded in the buckles of queen-rearing frames, and placed into colonies for queen rearing. In order to verify the feasibility of the tools, a paired comparative experiment was conducted using Apis mellifera, with the tools as the treatment group and manual larval grafting as the control group. We evaluated multiple key indicators, including acceptance rate of queen cells, queen cell length at emergence, emergence rate, weight of newly emerged queen, morphological indices (thorax length/width, forewing width, hindwing length, head width), ovariole number and the relative mRNA expression of four queen development-related genes (Vg, Hex110, Hex70b, Jhamt). No significant differences were observed in queen cell acceptance rate and emergence rate between the two groups. However, compared with the control group, queens reared using the tools exhibited significantly greater queen cell length at emergence, higher emergence weight, superior morphological traits, more ovarioles and significantly upregulated expression of all four assayed genes. In conclusion, the tools can be used to rear high-quality Apis mellifera queens effectively with superior phenotypic and molecular traits compared to conventional grafting, which provides efficient and convenient queen-rearing tools for beekeepers.