Selective responses and realized heritability estimation for a cultured Haliotis diversicolor aquatili population

Taking the F2 generation of Haliotis diversicolor aquatili descended from the hybridization between Chinese cultured population and Japanese wild population as the base population, we carried out a selective breeding experiment by mass selectionto investigate the selective responses and to estimate the realized heritability. We selected 10% individuals of the largest shell length as parents for the selected groups (SS), then randomly selected the other 10% individuals from the base population as parents for the control groups (SC), and the mass selection experiment has a selective intensity of 1.755. Results reveal that no significant difference was found in egg size and fertilization rate (P0.05), while the selected groups show growth advantages in various degrees compared to the control groups in the larval settlement rate, larval metamorphosis rate, larval survival rate and postlarval growth (P0.05). The survival rate of 50-dph juvenile abalone in selected groups reached 35.07%, significantly greater than that in control group which is 23.62% (P0.05). The ranges of the selective responses and realized heritability of 40~270-dph individuals in selected groups are 13.64%~81.88% (31.63% on average) and 0.21~0.53 (0.36 on average), respectively. The average shell length in selected groups is significantly greater than that in control groups (P0.01). Therefore, the experiment indicates that the mass selection is effective for the genetic improvement for cultured H. diversicolor aquatili populations.