清水江鲤外部形态性状对体质量的影响

Mathematical Analysis of Morphometric Traits Effects on Body Weight for Qingshui River Cyprinus carpio

随机选取117尾体长在260~350 mm的野生清水江鲤个体,分别测定其体质量、体长、全长、体高、体厚、头长、尾柄长、尾柄高等8个形态学指标,研究清水江鲤外部形态性状对体质量的影响。采用相关分析、通径分析及多元回归分析方法,分别确定了清水江鲤形态性状对体质量的相关系数、通径系数和决定系数,剔除了与体长存在显著性共性的全长指标,构建了显著性形态性状与体质量的多元回归方程。结果表明,清水江鲤形态性状中,体质量的变异系数最大;各形态性状与体质量的相关系数均达到显著水平(P<0.05);体长、体高、体厚、尾柄高、尾柄长等5个性状对体质量的通径系数达到极显著水平(P<0.01),其中体高的通径系数最大,为0.582,尾柄长的通径系数最小,为-0.123;决定分析结果同通径分析结果趋势一致,显著性状对体质量的共同决定系数为0.911;采用逐步引入-剔除自变量的方法,建立以尾柄高(X_1)、体长(X_2)、体高(X_3)、体厚(X_4)和尾柄长(X_5)估计清水江鲤体质量(Y)的最优回归方程:Y=-1 217.894+1 048.363X_1+329.480X_2+438.304X_3+453.326X_4-354.932X_5,经检验方程达到极显著水平(P<0.01)。表明体长、体高、体厚、尾柄高、尾柄长是影响清水江鲤体质量的主要性状。

A total amount of 117 Qingshui River Cyprinus carpio between 260 mm and 350 mm were randomly sampled for measuring body weight and seven morphometric traits,including body length,total length,head length,tail handle length,tail handle height,body depth and body width.The correlation coefficient,path coefficient and decision coefficient of each morphometric trait on body weight were calculated by statistical analysis. In addition,a regression equation using significant morphological traits as variables and body weight as dependent variable was established,while total length was eliminated because of co-linear with body length. The results showed that all the correlation coefficients achieved significant levels( P < 0. 05),while the morphological stability of body weight was higher than that all morphological traits. The path coefficients of body length,body depth,body width,tail handle length and tail handle height were all at extremely significant level( P < 0. 01),while the biggest was body depth( path coefficient = 0. 582). The results of determinant coefficients analysis was consistent with that path analysis. The high value of total decision coefficient at 0. 911 suggested that the main attributes have been selected. The morphometric attributes tail handle height( X_1),body length( X_2),body depth( X_3),body width( X_4) and tail handle length( X_5) were used to establish the optimum regression( P <0. 01) by step by step elimination as Y =-1 217. 894 + 1 048. 363 X_1+ 329. 480 X_2+ 438. 304 X_3+ 453. 326 X_4-354. 932 X_5.This research suggested that body length,body depth,body width,tail handle length and tail handle height were the key effective factor on body weight of Qingshui River Cyprinus carpio.