Genetic effects and genotype x environment interactions for growth-related traits in common carp, Cyprinus carpio L.

A diallel cross was conducted with three variants of red common carp, Cyprinus carpio, var. singuonensis, C carpio var. wuyuanensis and C carpio var. color, raised in two separate experimental stations. Additive effects, dominance effects, additive x environment (A x E) and dominance x environment (D x E) interactions of growth-related traits of 8-month-old fish were estimated by using a mixed genetic model. It was found that the traits of body weight (BW), standard length (SL) and pre-dorsal height (PDH) were mainly controlled by dominance effects, whereas they were very weakly controlled by the additive, genotype x environment (A x E and D x E) interaction effects. For the trait of pre-dorsal width (PDW), additive effects were the predominant effects, while dominance and genotype x environment interaction effects were less important, Also, significant D x E interaction effects in BW, and significant A x E interaction effects in PDH and PDW were detected. In all the studied traits, the prediction of genetic merit (breeding values) for the three variants indicated that C carpio var. color was the best one for genetic improvement through direct selection in different environmental conditions, and the cross combination of C carpio var. color and C carpio var. singuonensis was the best for heterosis utilization by hybridization, while C carpio var. wuyuanensis was the best for improving the body height in red common carp. (c) 2007 Published by Elsevier B.V.