九孔鲍选择群体F1的选择反应与现实遗传力估计

以中国九孔鲍（Haliotis diversicolor aquatili）养殖群体与日本野生群体杂交子二代为选育基础群体，采用群体选育方法进行九孔鲍的选择育种研究，以估计该养殖群体的选择反应与现实遗传力。截断选择壳长最大的10％个体作为选择组亲本（SS），从基础群体中随机抽取相同数量的个体作为对照组亲本（sc），选择强度为1．755，结果表明，选择组与对照组在卵径、受精率方面无显著的差别（P〉0．05），但选择组在幼体附着率、幼体变态率、幼体成活率及稚贝早期生长方面与对照组相比表现出不同程度的生长优势（P〈0．05），选择组50日龄的稚鲍成活率达到35．07％，显著大于对照组23．62％（P〈0．05），40—270日龄的选择组壳长选择反应和现实遗传力变化范围分别为13．64％～81．88％和0．21～0．53，平均为31．63％和0．36，选择组平均壳长显著大于对照组（P〈0．01）。研究初步显示，养殖群体的选择反应极显著，群体选育是养殖九孔鲍遗传改良的有效途径。

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 popula- tion and Japanese wild population as the base population, we carried out a selective breeding experiment by mass selection to investi- gate 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 （ P 〉 0. 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 （P 〈 0.05 ）. The survival rate of 50-dph juvenile abalone in selected groups reached 35.07%, significantly greater than that in control group which was 23.62% （P 〈 0. 05）. The ranges of the selective responses and realized heritability of 40 - 270-dph individuals in selected groups were 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 was significantly greater than that in control groups （P 〈 0. 01 ）. Therefore, the experiment indicates that the mass selection is effective for the genetic improvement for cultured H. diversicolor aquatili populations.