Abstract:In order to screen the high-quality combination of donor and host mussels, explore the difference and correlation on the growth traits of different pearl mussels after graft operation, compare the difference of the pearl-forming percentage and size in each combination, by using Hyriopsis cumingii, Hyriopsis schlegeli, Kangle clam[Hyriopsis cumingii(♀) x Hyriopsis schlegeli(♂)] and Cristaria plicata as donor and host mussels respectively, 16 pearl mussels combinations were obtained. In addition, 4 species pearl mussels without graft operation were taken as control group. 16 combinations and 4 control groups were compared by measuring the growth traits (body weight, shell length, shell height and shell width) at the first year after grafting, and as the same time the correlation of growth traits of each combination was analyzed. The number and size of non-nucleated pearl in each combination was measured, the pearl formation percentage and roundness were calculated and the difference among different combination was analyzed. The results showed that the growth traits were greater than corresponding values of control group when H.cumingii, H.schlegeli were host mussels. However, the growth of C.plicata groups was inhibited; Except for the C-C group, the correlation coefficient between shell length and body weight was the largest (0.824~0.972) among each group. The correlation coefficient between shell width and body weight of C-C group was largest(0.782); The combinations among H.cumingii, H.schlegeli and Kangle clam had higher pearl formation percentage (98.75%~100%). And the pearl formation percentage of S-S, S-C and C-C groups reached 100%. The pearls when H.cumingii, H.schlegeli were host mussels were larger in size and rounder in shape. There was a significant positive correlation between the size of pearls and the percentage difference of diameters in all pearl combinations. The results showed that S-S、S-C、C-C groups worked best. The results provided an important basis for the exploration of the correlation between the growth traits of different pearl mussels and the comparison of the pearl-forming rate and size of the seedless pearls produced.