Population and family growth response to different rearing location, heritability estimates and genotype × environment interaction in the silver-lip pearl oyster (Pinctada maxima)
Résumé
Genetic parameters and genotype by environment interactions were estimated from the growth responses of silver-lip pearl oyster (Pinctada maxima) families originating from three populations (Aru, Bali, West Papua) reared at two Indonesian commercial sites (Bali and Lombok). Microsatellite-based DNA parentage analyses were used to assign oysters to their family and population of origin and four shell growth traits (anterior–posterior measurement (APM), dorsal–ventral measurement (DVM), shell width (SW) and wet weight (WW)) recorded at 14 and 18 months of age. Significant size differences were observed in all shell growth traits between oyster populations, and between oysters cultured at the different locations. Oysters from Bali and West Papua grew faster than those sourced from Aru at both culture sites, whilst the Lombok site produced the fastest growing oysters overall. Significant size differences were also present in shell traits among families, indicating a large amount of genetic variability present for potential breeding programs. Although there were significant familial size differences for shell traits, genetic correlation analyses showed little evidence for re-ranking of family performance among the two culture sites (rg = 0.89–0.99), suggesting low genotype by environment deviations among sites. Heritability of the shell traits DVM, APM and WW was moderate (0.15 ± 0.003 (DVM), 0.23 ± 0.030 (APM)) and as a consequence should respond to targeted selection.