Comparative analysis of growth traits and shell-closing strength among hybrid populations from three geographical groups of pearl oyster (Pinctada fucata)

We collected three geographical pearl oyster (Pinctada fucata) populations from Sanya (SY), Shenzhen (SZ) and Vietnam (YN) to establish nine breeding populations by using complete diallel crosses. Then we chose 100 twenty-month-old individuals randomly from each breeding population to measure four morphological traits (shell length, shell height, shell width and hinge length), four qualitative traits (body weight, shell weight, viscera weight and adductor muscle weight) and shell-closing strength trait. The correlation analysis showed positive correlation between shell-closing strength and the other various traits. The largest correlation coefficient was 0.601 between shell-closing strength and shell weight, followed by body weight (0.564), and the smallest was 0.320 for shell width. With comparison of morphological traits and qualitative traits, theelite populations were YNSY, SYSZ and YNSZ. Based on shell-closing strength, theelite populations were YNSY, YNSZ and SZYN. Based on growth traits and shell-closing strength, twoelite populations (YNSY and YNSZ) had good potential for further selection as breeding materials.