四种不同引进群体的凡纳滨对虾种虾形态差异性分析

种虾资源的好坏影响着整个凡纳滨对虾(Litopenaeus vannamei)产业的发展，从国外引进不同的种虾群体可以在一定程度改善我国的种虾资源。本研究以凡纳滨对虾种虾(所选种虾均为雌虾，在12~15月龄之间)为研究对象，运用聚类分析、主成分分析和判别分析等方法对4种不同来源的引进群体(PRIMO群体、SIS群体、厄瓜多尔群体和API群体)进行形态差异比较分析。结果显示，各性状的变异系数除了体质量外，其他均低于15.000%。单因素方差分析结果显示，在10个性状的比例参数中，头胸甲宽/头胸甲长和腹部宽/腹部长在4个种虾群体中无显著差异。聚类分析结果显示，PRIMO与SIS群体形态差异最小，与厄瓜多尔和API群体的趋异程度逐渐增加。主成分分析构建了4个主成分，累积贡献率为88.861%，其中，主成分1、2、3和4的贡献率分别为32.606%、23.982%、17.569%和14.704%。判别分析建立了4种不同来源的引进群体的判别函数，判别准确率P1为33.3%~67.1%，P2为30.8%~69.5%，综合判别准确率为52.1%。4个凡纳滨对虾种虾群体在某些性状比例参数上差异显著，在一定程度上产生了形态差异，但尚未达到亚种水平。

Morphological differences in four introduced populations of Litopenaeus vannamei

The quality of ovigerous female resources affects the development of the Litopenaeus vannamei industry, and the introduction of different ovigerous female groups from abroad can improve the ovigerous female resources in China. However, it is important to analyze the morphological characteristics of the introduced populations to breed high-propagation and high-growth L. vannamei and obtain high-quality germplasm. Here, cluster analysis, principal component analysis, and discriminant analysis are used to analyze the morphological differences of four imported L. vannamei populations. The coefficient of variation for each trait was less than 15.000%, except body weight. One-way analysis of variance (ANOVA) showed no differences in carapace width / carapace length and abdomen width / abdomen length among the four populations. Cluster analysis showed minimal differences between the PRIMO and SIS groups, and the degree of differentiation between the Ecuador and API groups gradually increased. Four principal components were constructed by principal component analysis, and the cumulative contribution rate was 88.861%. The contribution rate of principal component 1 was 32.606%, principal component 2 was 23.982%, principal component 3 was 17.569%, and principal component 4 was 14.704%. Discriminant analysis established discriminant functions for the four groups, and the discriminant accuracy P1 was 33.3%~67.1%, P2 was 30.8%~69.5%, and the comprehensive discriminant accuracy was 52.1%. The coefficient of difference for each trait ratio of the four ovigerous female populations was less than 1.28, indicating morphological differences among the four L. vannamei populations. However, the morphological differences did not reach sub-species levels.