Pollination efficiency
The GLM analysis showed that the pollen removal (22750 ± 456, N = 20) and pollen deposition (748 ± 33, N = 20) of X. appendiculata were the most among five visitor species (Wald χ2 = 428.94, df = 4, P< 0.001, and Wald χ2 = 369.91, df = 4,P < 0.001) (Fig. 6A and B). The pollination efficiency of X. appendiculata (0.033 ± 0.002) and X. dissimilis(0.032 ± 0.002) were relatively higher than that of the other three pollinator species (Wald χ2 = 187.35, df = 4, P < 0.001) (Fig. 6C). In terms of four bee species, the pollen removal (11556 ± 548, N = 20) and pollen deposition (306 ± 19, N = 20) of A. mellifera were the fewest (Wald χ2 = 181.87, df = 4, P< 0.001, and Wald χ2 = 164.78, df = 3,P < 0.001) (Fig. 6A and B), and the pollination efficiency of A. mellifera were the lowest (Wald χ2 = 10.17, df = 4, P = 0.02) (Fig. 6C). The pollen removal (5896 ± 459, N = 20) and pollen deposition (19 ± 4, N = 20) of M. pyrrhosticta were relatively fewer than that of four bee species (P < 0.001) (Fig. 6A and B), and the pollination efficiency (0.004 ± 0.001, N = 20) of M. pyrrhostictawas also relatively lower than that of four bee species (P< 0.001) (Fig. 6C).