华贵栉孔扇贝1龄贝数量性状的相关性及通径分析

为了查明华贵栉孔扇贝数量性状间的相关性及影响产量的因素组成,随机选取203只1龄贝,对其形态性状(壳长、壳高、壳宽)和重量性状(活体重、闭壳肌重)等5个数量性状进行测量,并应用遗传相关、多元回归、通径分析等方法对数据进行了分析.结果表明受测的5个数量性状间的相关系数均达到极显著水平(P<0.001).3个形态性状对2个重量性状的影响并不相同:对活体重起直接作用最大的是壳高,其直接决定作用达20.31%,通过壳长的间接决定作用达25.27%;对闭壳肌重直接作用最大的是壳长,其直接决定作用达22.48%,通过壳宽的间接决定作用达16.10%.建立了利用形态性状估计重量性状的回归方程.该结果为华贵栉孔扇贝选择育种提供了理论依据,即以提高活体重为目标,主要选择壳高,同时加强对壳长的协同选择;以提高闭壳肌重为目标,主要选择壳长,同时加强对壳宽的协同选择.

Correlation and Path Analysis to Quantitative Traits of Noble Scallop Chlamys nobilis Reeve at one-year Old

To clarify correlation among quantitative traits and compositions influencing production, five quantitative traits including three morphological traits (Shell length, shell height, and shell width) and two weight traits (Body weight and adductor weight) of noble scallop Chlamys nobilis Reeve were measured and analyzed from 203 randomly chosen individuals at one-year-old by correlation analysis, path analysis, and multiple regression analysis. The results showed that there were significant correlations (P < 0.001) among the five measured traits. And different morphological traits made different directly predominant effects on two weight traits. Shell height gave predominant effects on body weight, whose directly predominant effect was up to 20.31%, and whose indirectly predominant effect via shell length was up to 25.27%. Shell length gave predominant effects on adductor weight, whose directly predominant effect was up to 22.48%, and whose indirectly predominant effect via shell width was up to 16.10%. Regression equations between weight traits and morphological traits were also established. The present results provide a theoretical basis for selective breeding in noble scallop, that is, shell height should be firstly selected and shell length should be simultaneously selected in order to improve body weight via morphological traits, whereas shell length should be firstly selected and shell width should be simultaneously selected in order to improve adductor weight via morphological traits.