Abstract: 【Objective】The objective of this study is to compare the queen quality of queen-rearing with and without larvae-grafting and investigate whether methyl palmitate (MP) and methyl linoleate (ML) used in the process of queen rearing could improve the queen quality.【Method】Three colonies of Apis cerana cerana were chosen as experimental colonies, each colony with 5 combs, were basically the same in the honeybee population, queen age and brood comb area. These colonies were maintained using standard beekeeping techniques. Another strong colony with well egg-laying queen was served as egg-laying colony. The queen was reared at least 3 times in each colony during the queen-rearing with and without larvae-grafting experiment. And the queen was reared at least 3 times for different brood pheromone in each colony with queen-rearing with larvae-grafting method. Stimulated fed the colony to improve the worker nursing enthusiasm during the period of queen-rearing. Comparing the queen quality by testing the acceptance rate of queen cells, the weight, thorax weight and width of newly-emerged queens reared from the queen-rearing with and without larvae-grafting. The gene expression of vitellogenin (Vg) and transferrin (Trf) of the queens were tested by qRT-PCR, and the ovarioles were counted by paraffin section. In order to verify whether MP or ML used in the process of queen-rearing can improve the queen quality, 1µL solution which contains 0, 0.1%, 1.0% and 10.0% of MP or ML was added into the queen cells with 60-63 h old queen larvae, respectively. The queen quality was also detected.【Result】The rate of brood accepted and the percent of queen emerged in queen-rearing without larvae-grafting was 40.87% and 38.52%. In queen-rearing with larvae-grafting it was 74.38% and 69.13%, respectively. So apparently it is easier to accept the wax queen cell than the plastic for workers. No significant difference in the newly-emerged weight, thorax weight and width, ovarioles number in one side and Trf expression was observed between these two queen-rearing methods (P＞0.05). It was also similar in the average value. Nevertheless, Vg expression in queens from queen-rearing without larvae-grafting was significantly higher than that in the larvae-grafting (P＜0.05). 0.1% ML and all concentrations of MP showed no significant effect on all parameters (P＞0.05), and gene expression of Trf was also not different among all treatments (P＞0.05). 1.0% ML significantly reduced the newly-emerged weight, thorax weight and Vg expression of queens (P＜0.05), and 10.0% ML significantly reduced the index, ovarioles number and Vg expression of queens (P＜0.05). There was no significant effect on Trf expression level in both MP and ML (P＞0.05).【Conclusion】The acceptance rate of queen cell was significantly lower (P＜0.05) in queen-rearing without larvae-grafting compared with larvae-grafting. There was no significant difference in the newly-emerged weight, thorax weight and width, ovarioles number and Trf expression of the queens between queen-rearing with and without larvae-grafting (P＞0.05), but Vg expression was considerably higher whereas the acceptance rate of queen cells was lower in queen-rearing without larvae-grafting (P＜0.05). ML and MP used in queen-rearing process could not improve the queen quality.

Key words: Apis cerana cerana, queen-rearing without larvae-grafting, methyl palmitate, methyl linoleate, queen quality