罗氏沼虾野生和养殖群体形态性状对体重的影响

Effects of morphological characters on body weight of wild and cultured populations of Macrobrachium rosenbergii

本研究测定了罗氏沼虾(Macrobrachium rosenbergii)缅甸野生、泰国和越南养殖群体共109尾个体的全长、体长和体重等10个形态性状,综合运用相关分析法、通径分析法和回归分析法分析野生和养殖群体主要形态性状对体重的影响。结果显示:3个群体体重的变异系数均较大,显示出较大的选育潜力,其中缅甸野生群体选育潜力最大。除第2腹节长外,群体间其他形态性状的变异系数均是缅甸野生群体最大,越南养殖群体最小,形态性状存在显著的群体差异。缅甸野生群体的头胸甲宽、第2腹节长和第2腹节宽对体重的通径系数达到极显著水平。泰国养殖群体的全长、头胸甲宽和第2腹节长对体重的通径系数达到显著或极显著水平。越南养殖群体的头胸甲长和第2腹节宽对体重的通径系数达到极显著水平。此外,缅甸野生和泰国养殖群体的第2腹节长对体重都呈负相关作用。各群体所筛选出的形态性状对体重回归方程的回归关系均达到极显著水平,缅甸野生、泰国和越南养殖群体所筛选出的形态性状对体重的决定系数R 2分别为0.982、0.941和0.933。结果表明,在实际生产中,可基于群体形态性状对体重的多元回归方程,对体重通径关系达到显著或极显著水平的形态性状可作为定向选育指标。

A total of ten characters of 109 Macrobrachium rosenbergii individuals from Myanmar wild population,Thailand and Vietnam cultured populations were measured in this study,including total length,body length and body weight.Correlation,path,and regression analyses were used to analyze the effects of main morphological characters on body weight in the wild and cultured populations.The results showed that the coefficients of body weight variation were significant in the three populations,showing great breeding potential,among which Myanmar wild population had the most significant breeding potential.Except for the second uromere length,the coefficients of variation of other morphological characters among populations were the largest in Myanmar wild population and the smallest in Vietnam cultured population.There were significant population differences in morphological characters.The path coefficients of carapace width,the second uromere length and the second uromere width on body weight of Myanmar wild population reached an extremely significant difference level.The path coefficients of the total length,carapace width and the second uromere length on body weight of Thailand cultured population reached a significant difference level or an extremely significant difference level.The path coefficients of carapace length and the second uromere width on body weight of Vietnam cultured population reached an extremely significant level.In addition,the second uromere length of Myanmar wild population and Thailand cultured population was negatively correlated with body weight.The regression equations of morphological characters screened from each population on body weight were established and regression relationships of equations reached an extremely significant level.The determination coefficients R2 of morphological characters screened from Myanmar wild population,Thailand and Vietnam cultured populations on body weight were 0.982,0.941 and 0.933,respectively.In practical production,the multiple regression equations of population morphological characters on body weight could be the meaningful parameters.The path relationship of morphological character reaches a significant or an extremely significant level on body weight can be used as a directional breeding index of M.rosenbergii.