砂海螂群体表型性状和重量性状的相关及通径分析

Correlation and path analysis of Mya arenaria group phenotypic traits and weight traits

从大连旅顺龙王塘海域的四龄野生砂海螂(Mya arenaria)群体中随机选取50个个体,测量其壳长(X_1)、壳高(X_2)、壳宽(X_3)以及重量性状活体重(Y_1)、软体重(Y_2)等5项性状,计算性状间的相关系数,采用相关与通径分析方法分析了表型性状对重量性状的影响。结果表明受测的5个数量性状间的相关性均达到显著水平(P<0.05),相关系数从0.676到0.931。表型性状对活体重和软体重具有相同的影响:对二者起直接作用最大的均是壳长,其值分别为31.80%和23.90%;对二者起间接作用最大的均为壳宽,其值分别为10.80%和8.40%;壳高的作用最小。多元回归分析分别建立了壳长(X_1)、壳高(X_2)、壳宽(X_3)与活体重(Y_1)和软体重(Y_2)关系的回归方程,分别为:Y1=1.421X_1+1.563X_2+0.722X_3-125.360,Y2=0.348X_1+0.390X_2+0.169X_3-28.119。研究结果为砂海螂选择育种提供了理论依据,即以提高活体重或软体重为目标,主要选择壳长,同时加强对壳宽的协同作用。

Fifty individuals were randomly selected from the four instar in the wild populations of Mya arenaria Dalian Lushun Longwangtang waters. And then, the measurement of shell length( X_1),shell height( X_2),shell width( X_3) and weight( Y_1),the shape of living body weight and soft body weight( Y_2)were performed,while correlation coefficient between characters was also calculated. The effects of phenotypic traits on weight traits were analyzed by means of correlation and path analysis. The results showed that the correlation between the 5 quantitative traits reached significant level( P < 0. 05). The correlation coefficient was from 0. 676 to 0. 931. Phenotypic traits had the same effect on living body weight and soft body weight.The largest of the two direct effects were shell length,while their values were 31. 80% and 23. 90%,respectively. The largest indirect effects of the two were shell width,while their values were 10. 80% and 8. 40%,respectively,and shell height was the least. Multiple regression analysis was established for the regression equations of shell length( X_1),shell height( X_2),shell width( X_3) with 3 estimates of living body weight( Y_1) and soft body weight( Y_2) as: Y_1= 1. 421 X_1+ 1. 563 X_2+ 0. 722 X_3-125. 360 and Y_2= 0. 348 X_1+ 0. 390 X_2+ 0. 169 X_3-28. 119. The results provided a theoretical basis for Mya arenaria selective breeding: in order to improve the living body weight or soft body weight,the shell length was the main consideration,while strengthen the coordination of shell width should be also considered.