养殖条件下不同年龄背瘤丽蚌(Lamprotula leai)数量性状的相关与通径分析

CORRELATION AND PATH ANALYSIS OF QUANTITATIVE TRAITS OF DIFFERENT-AGE LAMPROTULA LEAI IN ARTIFICIAL BREEDING

随机选取养殖2龄、3龄和4龄的背瘤丽蚌(Lamprotula leai)各30个,分别测定壳长、壳高、壳宽、壳厚、活体重和壳重等数量性状参数并计算了各性状间的相关系数。应用Duncan法多重比较分析了不同年龄个体的形态差异,以壳重为因变量,其它数量性状为自变量进行多元回归和通径分析,计算了对应的通径系数和决定系数,并建立了最优回归方程。结果表明:2龄蚌和3龄、4龄蚌之间在形态上具有显著差异;不同年龄背瘤丽蚌各数量性状(2龄蚌壳厚除外)与壳重均极显著相关(P<0.01);通过对各年龄段各种性状对壳重的通径分析和决定系数分析,发现活体重对壳重的通径系数分别为0.900、0.902和0.923,决定系数分别达到0.81000、0.81360和0.85193,是影响壳重最主要的性状。采用逐步回归法,剔除偏回归系数不显著的性状,建立了数量性状对壳重的最优回归方程。基于对壳重决定效应的大小,活体重可作为背瘤丽蚌良种选育的目标性状。

To study the correlation between quantitative traits and shell weight, 30 individuals of cultured Lamprotula leai in each group of two-, three-, and four-year-old ones were sampled randomly. Six quantitative traits were measured, including the length, height, width, and thickness of shell, body weight, and shell weight. The data were statistically processed by Duncan multiple comparisons, correlation analysis, path analysis, and stepwise regression analysis. Results show that differences in morphology among group was significant(P<0.05). Pearson correlations between quantitative traits(except for the shell thickness of the two-year old mussel) and shell weight reached highly significant levels(P<0.01) at all ages. Path and coefficient analyses on traits effect on shell weight showed that the path coefficient of the 3 age groups were 0.900, 0.902, and 0.923, and the determination coefficients reached 0.81000, 0.81360, and 0.85193, respectively. Multiple regression equations were established in age-specific manner. We proposed that the shell weight is the target trait for selective breeding of L. leai.