菲律宾蛤仔（Ruditapes philippinarum）海洋橙品系两个世代的杂交与近交效应

摘要

In order to improve the phenotypic characteristics of Ocean Orange strain of Manila clam Ruditapes philippinarum, the effect of hybridization and inbreeding between two generations on this strain were investigated by establishing inbreeding groups （F22, F33）, hybrid groups （F23, F32）, and control groups （C22, C33） with the parent of full-sib F1 and F2 （the up-selection rate 10%）, in August of 2009. The results showed that the characteristics on growth of larvae and juveniles were partially improved, whereas the survival rate did not show any sign of improvement through hybridization. The slight improvement in growth through heterosis was observed on larvae （1.68） and juvenile （2.40）; Single-parents heterosis of reciprocal groups were asymmetry, the heterosis of larval and juvenile for F23 were 3.64 and 11.71, for F32 were -0.13 and -5.02, respectively. The mid-parent survival weakness of larvae and juvenile were -1.54 and -5.59; the survival weakness of F23 for larvae and juveniles were -3.37 and -7.65, for F32 were -0.55 and -3.61, respectively. Influences from maternal mainly impacted hybrid from larvae to juvenile. Survival rate of two generations and growth of F33 were improved by inbreeding. The inbreeding depression rate of growth for larval and juvenile for F22 was 2.33 and 7.59, whereas for F33 was -3.09 and -8.05, respectively. The inbreeding depression rate of survival for larval and juvenile for F22 were -4.75 and -1.04, and for F33 were -11.09 and -7.63, respectively. The mating strategy was the major factor for inbreeding effects during the larval period, then the generation effect became the major factor during juvenile period. The phenotypic characteristics of this strain were effectively improved by close combination among up-selection, hybridization and inbreeding.%于2009年8月以菲律宾蛤仔海洋橙品系的全同胞子一代和子二代上选10%的个体作为亲本,通过建立近交组合（F22、F33）、杂交组合（F23、F32）和设置对照组（C22、C33）,研究了两个近交世代的杂交效应及近交效应,以提高菲律宾蛤仔海洋橙品系的表型性状。结果表明,杂交使幼虫和稚贝的生长性状得到了部分改良,但存活性状尚未得到提高。幼虫和稚贝表现出微弱的生长优势,正反交组单亲生长优势表现出正负不对称性。杂交效应主要受到母本效应的影响,母本效应贯穿于幼虫期及稚贝期。近交使世代F33的生长性状得到了改良,且两