合浦珠母贝不同壳色选育系F6数量性状的相关性和通径分析

为深入了解不同壳色合浦珠母贝(Pinctada fucata)形态性状与体重间的关系,为亲贝的选择提供策略,本研究使用合浦珠母贝传统壳色、金壳色、白壳色、红壳色和黑壳色5种壳色选育系F6各1000只个体的性状数据进行通径分析和聚类分析。测量的性状包括壳长(SL,mm)、壳高(SH,mm)、壳宽(SW,mm)、绞合线长(HL,mm)和体重(BW,g)。结果显示,5种壳色合浦珠母贝所有形态性状与体重间的相关系数均达到极显著(P0.01)。通径分析表明,壳长对传统壳色和白壳色贝体重的直接影响最大,壳高对金壳色和红壳色贝体重的直接影响最大,壳宽对黑壳色贝体重的直接影响最大。利用多元回归方法构建不同壳色合浦珠母贝形态性状与体重(BW,g)间的回归方程,其中传统壳色:BW=-24.999+0.467SL+0.387SH-0.259SW+0.244HL;金壳色:BW=-38.661+0.305SL+0.477SH+0.242SW+0.375HL;白壳色:BW=-4.130+0.332SL+0.300SH-0.307SW+0.088HL;红壳色:BW=-27.307+0.327SL+0.321SH+0.252SW+0.305HL;黑壳色:BW=-40.921+0.278SL+0.335SH+1.076SW+0.269HL。聚类分析显示,传统壳色与金壳色形态特征相近,而白壳色、红壳色和黑壳色形态特征相近。

Correlation and path analyses of quantitative traits in different shell color F6 lines of pearl oyster (Pinctada fucata)

To determine the effect of main morphological traits on the body weight of Pinctada fucata and to offer strategies for parent selection during the breeding of P. fucata, the correlations between the morphometric attributes and body weight of P. fucata were explored by the correlation, path, and regression analyses. One thousand individuals from each of traditional shell, golden shell, white shell, red shell, and black shell oysters were randomly sampled to measure their body weight (BW, g) and four morphometric attributes, including the shell length (SL, mm), shell height (SH, mm), shell width (SW, mm), and hinge length (HL, mm). The correlation coefficients among all variables were calculated. The path coefficients were calculated by setting the body weight as a dependent variable and other attributes as independent variables via stepwise elimination. The results showed that the four morphometric attributes of the five kinds of oysters extremely significantly (P<0.01) correlated with body weight. The shell length presented the highest correlation with the body weight of traditional, white, and red shell oysters, and the shell height showed the highest correlation with the body weight of golden and black shell oysters. The results of the path coefficient analysis showed that the shell length of traditional and white shell oysters, the shell height of golden and red shell oysters, and the shell width of black shell oysters showed the highest correlation with body weight, and exhibited predominant direct effect and determinacy on the body weight for P. fucata. The multiple regression equations were obtained to estimate body weight as traditional shell color:BW=-24.999+0.467SL+0.387SH-0.259SW+0.244HL; golden shell color:BW=-38.661+0.305SL+0.477SH+0.242SW+ 0.375HL; white shell color:BW=-4.130+0.332SL+0.300SH-0.307SW+0.088HL; red shell color:BW=-27.307+0.327SL+ 0.321SH+0.252SW+ 0.305HL; black shell color:BW=-40.921+0.278SL+0.335SH+1.076SW+0.269HL. The clustering results showed that the morphological traits were more similar between the traditional and golden shell oysters and between the white, red, and black shell oysters.