两月龄日本囊对虾形态性状对体质量的通径分析

Path Analysis of the Effects of Morphometric Traits on Body Weight for 2-month-old Marsupenaeus japonicus

选取人工养殖两月龄日本囊对虾442尾,共测量了11个形态性状.采用多元分析的方法,分别计算得出了各个形态性状对体质量(Y)的相关系数、通径系数以及决定系数,并且对于形态性状对体质量的直接作用和间接作用进行了进一步的分析.结果表明,在相关分析中,所有形态性状与体质量的相关系数均达到极显著水平(p<0.01).体长、头胸甲宽、第三腹节宽、第三腹节高对于体质量的通径系数达到极显著水平(p<0.01),其中通径系数最大的是体长.决定程度分析的结果显示,决定系数之和∑d=0.929 9,这表明体长、头胸甲宽、第三腹节宽、第三腹节高是影响体质量的主要形态性状.最终建立了以形态性状为自变量,体质量为因变量的最优多元回归方程Y=-1.862+0.352 X1+1.087 X3+0.983 X5+0.528 X11.

In breeding program,early selection of culture animal can enhance breeding efficiency. In order to find the morphometric traits which affect body weight most,442 2-month-old Marsupenaeus japonicus were randomly sampled for measuring eleven mor- phometric traits. By correlation and path analysis, the path coefficients and determination coefficients of each morphometric trait to body weight（Y） were evaluated. The effect of each morphometric trait on body weight was dissected as direct effect and indirect effect. The results showed that the correlation coefficients of each morphological trait to body weight were all at extremely significant level（P〈0.01 ）. The path coefficient of body length （ X1 ）, carapace width （ X3 ）, third segment width （ X5 ） and third segment height （X11）to body weight were all at extremely significant level（P〈0.01）. The total determination coefficient of all selected morphometric traits to body weight ∑d=0. 929 9（〉0.85）. Indicating that the morphometric traits included in this study were major factors in- fluencing body weight. We established the regression equation of the four correlated traits to body weight Y=-1. 862＋0. 352X1 ＋ 1. 087X3 ＋0. 983X5 ＋0. 528X11. This research result would support the breeding program of M. japonicus.