Analysis of grey relationship between morphological traits and body weight ofpearl oyster (Pinctada fucata)

We conducted a grey relational analysis to examine the relationship between shell traits and body weightof 12 selective breeding families of Pinctada fucata. The results show that the average body weight, shell length, shell height, shell width and hinge length were 35.96 g, 57.36 mm, 59.24 mm, 23.55 mm and 56.93 mm, respectively. The coefficients of variation in body weight and shell traits were ranked as follows: body weight (21.30%)shell length (9.91%)hinge length (9.12%) shell height (8.85%) shell width (8.30%). The grey relational degrees between each shell trait and body weight were ranked as follows: shell height (0.745 9)hinge length (0.714 8)shell width (0.705 9)shell length (0.682 5). It is suggested that shell height which had the closest relationship with body weight could be regarded as an important factor for evaluation of P.fucata breeding practice for high growth lines selection and improvement of selection efficiency.