Heritability estimates for copper/zinc accumulation capabilities and correlation with growth/quality traits in the Fujian oyster, Crassostrea angulata

Abstract Oysters are hyper-accumulators of copper (Cu) and zinc (Zn) and are a good food source for trace element supplements. However, increasing heavy metal pollution in estuaries and coastal areas has posed a critical threat to oysters and thus led to food safety issues. Here, we assessed if it is possible to obtain oyster varieties with differential metal-accumulated properties through genetic improvement. The narrow-sense heritabilities of Cu and Zn accumulation capabilities and growth traits in Fujian oyster ( Crassostrea angulata ) were estimated to determine the degree to which Cu and Zn accumulation is under genetic control. In addition, we investigated the trade-offs between Cu/Zn accumulation and some farming performances, including growth-related traits, and the contents of glycogen and eight free amino acids. Moderate estimates were observed for narrow-sense heritability of Cu (0.189 ± 0.061) and Zn (0.373 ± 0.091) accumulation capability, while growth-related traits showed moderate-high heritability (0.168 ± 0.059–0.595 ± 0.116). High-level genetic (0.802 ± 0.080) and phenotypic (0.853 ± 0.012) correlations were detected between Cu and Zn accumulation capability, while correlations between metal accumulation and growth traits were low (−0.023 ± 0.042–0.491 ± 0.200). Moreover, Cu and Zn accumulation in Fujian oyster exhibited no significant influence on the quality traits measured, except for Taurine (Tau). Tau contents in high Cu/Zn accumulated oysters were significantly higher than in low-accumulated oysters, suggesting an important role of Tau in Cu/Zn accumulation. Our results provide important information to guide effective selective breeding of Fujian oysters with specific Cu/Zn accumulation capabilities.