Studies on the growth characteristics and heterosis of genealogies of Pseudosciaena crocea.

In this study,the growth characteristics of four Pseudosciaena crocea groups including the selfing of DD(Daiquyang♀×Daiquyang♂),the selfing of GG(Guanjingyang♀×Guanjingyang ♂),their direct cross DG(Daiquyang ♀×Guanjingyang ♂),and back-cross GD(Guanjingyang ♀ × Daiquyang ♂) were determined.Results after 526 days of grow-out showed that the final mean weights were higher for the GG(330.514 g) and the GD(336.694 g) than those of the DD(278.975 g) and the DG(243.297 g).The 1-year-old DD grew in a lower rate,but after the winter,the growth rate of DD accelerated significantly:the growth rate in length was higher than the other three groups while the weight gain was not significantly different from the GG and the GD.That is,the growth potential of the DD at later stage was high.The order of the fullness on 526th day was DDDGGDGG.A superior cross GD was constructed,which displayed significant heterosis for growth and body shape.It was concluded that the GD had excellent economic and breeding potential.The growth curves(DD:W=0.020 6L2.942 7,R2=0.994 9;GG:W=0.013 9L3.099 4,R2=0.978 5;DG:W=0.022 9L2.913 6,R2=0.990 5;GD:W=0.017 7L3.007 9,R2=0.994 9) fitted according to weight and body length had the high degree.The weight could be estimated by their body length,and this growth curves model could be applied in the production.