Abstract:In order to study the effect of donor and host mussels on the quality of non-nucleated pearls in freshwater pearl mussel (Hyriopsis cumingii),the purple strain F5 of H.cumingii was chosen as materials.Before grafting the saibos into mantles,the growth traits (shell length,shell height,shell width and body weight) of donor and host mussels were respectively recorded,and the inner shell color parameters including L,a,b,dE of donor mussels were measured.At the 18th month after grafting,the specific growth rate and inner shell color of the host mussels were measured.Besides,the color,size,roundness,luster and weight of pearls were noted.The results showed that there was no significant correlation with the growth traits of the donor mussels and the non-nucleated pearl quality (P>0.05),and that extremely significant correlation existed between inner shell color of the donor and pearls color (P<0.01).Moreover,the greater the dE value of the donor mussels is,the higher percentage of purple pearl the mussel can produce,whereas,a higher percentage of white pearl was yielded when dE value of the donor mussels turns out to be lower.Specific growth rate of the host mussels had highly significantly positive correlation with the pearl size,luster and pearl yield (P<0.01).The degree of correlation:body weight> shell length> shell width> shell height.Specific growth rate of the host mussels is anremarkably correlated with pearl roundness (P<0.01).The degree of correlation:shell length> body weight> shell width> shell height.No significant correlation between the inner shell color of the host mussels and the non-nucleated pearl quality was found (P>0.05).In consideration of all the correlations above,it can be concluded that the pearl color is probably improved by improving the inner shell color of the donor mussels,and that non-nucleated pearl quality (size,luster,roundness,pearl yield) can be greatly enhanced by promoting growth traits of the host mussels.