斑石鲷形态性状对体质量影响的通径分析

Path Analysis of Effects of Morphometric Traits on Body Weight of Oplegnathus punctatus

选择一龄斑石鲷60尾,测定其全长(X1)、体长(X2)、头长(X3)、体高(X4)、体宽(X5)、尾柄长(X6)、尾柄高(X7)和体质量(Y)共8个性状,运用相关分析、通径分析和多元回归分析研究7个形态性状对体质量的影响。结果表明:斑石鲷各形态性状与体质量间的表型相关均达到极显著水平(P<0.01)。通径分析显示,全长和尾柄高对体质量的通径系数达到极显著水平(P<0.01),是直接影响体质量的主要指标,其中以全长对体质量的直接影响最大。经逐步回归分析剔除偏回归系数不显著的形态指标后,建立全长和尾柄高对体质量的回归方程为Y=-295.686+16.633 X1+77.175 X7。研究表明,全长和尾柄高与体质量的复相关系数(R2)为0.976,为影响体质量的主要自变量。

The effects of morphometric traits on body weight of Oplegnathus punctatus were analyzed.Besides body weight（ Y）,morphometric traits including the total length（ X1）,body length（ X2）,head length（ X3）,body depth（ X4）,body width（ X5）,caudal peduncle length（ X6） and caudal peduncle depth（ X7） were measured for 60 one-year-old O. punctatus. The correlation coefficients among all traits were calculated,and the path and determination coefficients were calculated by taking the body weight as a dependent variable,and the other seven morphometric traits as independent variables in path analysis. The results of correlation analysis showed that there were significantly correlations between seven morphometric traits and body weight（ P 〈0. 01）. The path coefficients of two morphometric attributes（ total length and caudal peduncle depth） to body weight reached significant difference（ P 〈0. 01） level. The total length and caudal peduncle depth are very indicative of determining the body weight,among them total length weighted the most to the body weight,being a key effective factor. The stepwise regression analysis established a multiple regression equation onthe effects of body weight,which were presented as Y =- 295. 686 ＋ 16. 633X1＋ 77. 175X7. Judging from the high multiple-correlation coefficient（ R^2= 0. 976）,the main attributes（ total length and caudal peduncle depth） determining the body weight have been selected.