克氏原螯虾形态与体重的通径分析

[目的]确定影响克氏原螯虾体重的主要形态性状,以期为克氏原螯虾的亲本选育、形态辅助育种提供理论基础。[方法]选取了350尾雌性克氏原螯虾和302尾雄性克氏原螯虾,分别测量其体重(Y)、全长(X1)、头胸甲长(X2)、头胸甲宽(X3)、腹节总长(X4)、第一腹节长(X5)和第一腹节宽(X6)。采用相关分析、多元回归分析和通径分析,以体重为因变量形态性状为自变量,计算了雌雄克氏原螯虾各性状间的相关系数,通径系数和决定系数。[结果]相关分析结果显示,雌雄克氏原螯虾各性状间相关性皆达到了极显著水平(P<0.01)；多元回归分析中,雌雄克氏原螯虾剔除了与体重性状不显著的形态性状,建立的多元回归方程分别为Y雌=－34.689+10.629X2+6.479X3+0.803X1,Y雄=－33.413+5.727X2+6.770X3+2.043X1+3.045X6 ；通径分析结果表明,头胸甲长在雌性克氏原螯虾中对体重的直接作用最大,其次是全长和头胸甲宽,全长和头胸甲宽通过头胸甲长对体重的间接作用较大。在雄性中,也是头胸甲长的直接作用最大,其次是全长和头胸甲宽以及第一腹节宽,第一腹节宽通过头胸甲长、宽和全长对体重的间接作用最大。[结论]以上结果可为克氏原螯虾的选育奠定基础。

Path Analysis of Morphological Traits and Body Weight of Procambarus clarkii

[Objective] This study aimed to determine the main phenotypic traits that effect the body weight, and provide the theoretical basis for the parental selection and morphological assisted breeding of P. clarkii. [Method] A total of 350 female and 302 male P. clarkii were selected, and their weight(Y), full length(X1), carapace length(X2), carapace width(X3), abdomen length(X4), first abdomen length(X5) and first abdomen width(X6) were measured. The correlation analysis was adopted to calculate the correlation coefficients. The path coefficients and the decision coefficients were calculated by path analysis. [Result]The correlation analysis showed that all the correlations were highly significant between the traits of the female and male (P<0.01). In multivariate analysis, the morphological traits which did not reach the extremely significant level were eliminated and the multiple regression equations were presented as Y= －34.689+10.629X2+6.479X3+0.803X1 in female P. clarkii and Y=－33.413+5.727X2+6.770X3+2.043X1+3.045X6 in male P. clarkii. The results of the path analysis indicated that the carapace length had the greatest direct effect on body weight in female P. clarkii, followed by the full length, carapace width and the carapace width which mainly affected body weight indirectly through the carapace length. As for male, the carapace length also had the greatest direct effect on weight, followed by the full length, carapace width, the first abdomen width and the first abdomen which had the largest indirect effect on weight through the carapace length, carapace width and the full length. [Conclusion]The above results could lay a foundation for the parental selection in P. clarkii breeding.