Combining ability and heterosis analysis for reproductive traits of complete set selection lines in Oujiang color common carp, Cyprinus carpio var. color

Abstract

We performed complete diallel crosses from 5 complete set selection lines of Oujiang color common carp(Cyprinus carpio var.color).We then analyzed the combining ability and heterosis of 6 reproductive traits in the F1,including male gonadosomatic index(M_GSI),female gonadosomatic index(F_GSI),absolute fecundity(AF),relative fecundity(RF),fertilization rate(FR),and hatching rate(HR),using biostatistics and quantitative genetics methods.We observed obvious differences among the reproductive traits between the different mating combinations.The highest F_GSI and HR were found in combinations in which the mother was "whole red with small black spots"(RS).The highest AF and RF were observed in combinations in which the mother was "whole red"(WR).Conversely,the values for these reproductive traits were low for combinations in which the mother was "whole white with big black spots"(RB).The phenotypic correlations among F_GSI,AF,and RF were sig-nificantly positive(r=0.411?0.847,P=0.01?0.04).We detected significant specific combining ability(SCA) for F_GSI,AF,and RF.Ten combinations were detected with predicted specific combining ability(SCA) and heterosis(H).Additionally,there was a significant correlation between SCA and heterosis for M_GSI,F_GSI,AF,RF,and HR(r=0.959?0.985,P0.01).Our results provided baseline data to guide breeding of complete set lines of Ouji-ang color common carp.