双列杂交分析比较两个养殖群体杂交牙鲆抗病力

Analysis of intraspecific cross effects on complete diallel crosses in two stocks of Japanese flounder Paralichthys olivaceus

采用双列杂交设计对牙鲆Paralichthys olivaceus两个养殖群体:日本群体(J)和中国抗病选育群体(C)进行群体间杂交和群体内自繁,获得C(♀)×C(♂)、J(♀)×J(♂)、J(♀)×C(♂)和C(♀)×J(♂)4个交配组合的子一代。针对受精率、孵化率、白化率和存活率4个性状进行了组合间的比较,计算了各项性状的杂种优势率,对组间各性状进行了方差分析,并进行了相关分析。结果表明,杂交组在受精率、孵化率及存活率上存在着不同程度的杂种优势,其中C(♀)×J(♂)后代在孵化率和存活率两个性状上的杂种优势率分别为33.99%和31.37%。对4个性状的表型相关分析表明,受精率和孵化率的相关系数为0.657,受精率和存活率相关系数为0.432,分别达到了极显著水平(P<0.01)。分析结果认为,两个不同群体间的种内杂交是牙鲆优良品种培育的有效途径。

The first generation of four broodstock combinations, C（♀）×C（♂）、J（♀）×J（♂）、J（♀）×C（♂）and C（♀）×J（♂） were obtained from mating and crossing within and between Japanese broodstock （J） and China disease resistante broodstock （C） of Japanese flounder Paralichthys olivaceus using complete diallel crosses. Comparisons of fertilization rate, hatch rate, albinism rate and survivorship were made among four treatments in this study. Heterosis and correlations were found in different characteristics. The results showed that there were significant differences between the hybridization groups and self-fertilized groups on albinism rate and survival rate. Heterosis on hatch rate reached 33.99G and heterosis on survivor rate reached 31.37% in C C（♀）×J（♂） group. Correction analysis demonstrated highly significant correlations （P〈0.01） between fertilization rate and hatch rate （0. 657）, and fertilization rate and survival rate （0. 482）. These results indicated that the crosses between different stocks might be potentially effective for genetic improvement in Japanese flounder.