不同近交系数蛤仔橙色品系的生长和成活研究

摘要

We observed the shell length and survival between different coefficients of inbreeding to study the inbreeding depression for orange strain of Manila clam (Ruditapes philippinarum) through experiments.Four experimental groups were established,including first generation of half-sib (H1,F =0.125),first generation of full-sib (F1,F =0.250),fourth generation of full-sib (F4,F =0.594) and the control group (C1,F =0).The results show that the shell length of F1 is smaller than that of other groups at larval,juvenile,and grow-out stages.One-way ANOVA indicates that the difference in shell length is significant (P ＜0.05) between F1 and other groups at juvenile and grow-out stages,and that there are no significant differences among H1,F4 and C1.The growth rate of shell length in F1 decreases significantly,with a inbreeding depression rate ranging from 2.92％ to 18.33％,of which the mean value is (12.05 ±6.54) ％.Shell length in H1 has a depression at juvenile and grow-out stages as well.However,there is no inbreeding depression of length in F4 at any stages.There are no inbreeding depression of survival for H1,F1 and F4,as of which the survival rates are higher than that of control group C1.The results in this study suggest a basic theory to select the strain of Manila clam with orange shell color using the full-sib family.%以不同遗传背景的蛤仔(Ruditapes philippinarum)橙色品系为材料,采用建立半同胞家系子一代H1(F=0.125)、全同胞家系子一代F1(F=0.250)、全同胞家系子四代F4(F=0.594)及自然对照组C1(F=0)的方法,进行了不同近交系数蛤仔橙色品系生长和成活的研究.结果表明,在整个养殖周期中F1组的壳长生长最慢,在稚贝期和养成期均显著小于F4和C1组(P＜0.05),H1、F4和C1组之间的壳长生长差异不显著(P＞0.05).C1组的成活率在整个养殖周期中为最小,除幼虫期3日龄外,其他各日龄均显著小于其他试验组(P＜0.05),而H1、F1和F4组之间的成活率则差异不显著(P＞0.05).试验组F1壳长生长的衰退率为2.92％ ～ 18.33％,平均值为(12.05±6.54)％,试验组H1在稚贝期、养成期显现出一定的衰退现象,而试验组F4在整个养殖周期中均未表现出近交衰退现象;各试验组的成活性状在各日龄均未出现近交衰退.该研究为橙色品系的选育奠定一定的理论基础.