不同种群凡纳滨对虾形态性状对体质量的影响

采用单因素方差分析、通径分析和多元回归分析等方法,比较取自美国塞班岛凡纳滨对虾养殖基地V101、OS、G24、NS 4个凡纳滨对虾种群的头胸甲长、第1~6腹节长、尾节长、体长、全长、头胸甲宽、第1~6腹节宽、头胸甲高、第1~6腹节高等24项形态性状和体质量(m)及其所有性状的比例参数,分析各群体形态差异以及主要形态性状对体质量的影响,并建立回归方程。试验结果表明,4个群体大部分形态差异显著(P0.05),V101和G2群体属于瘦长型,OS和NS属于高胖型。相关分析、通径分析、决定程度分析结果表明,V101群体头胸甲长和头胸甲高与体质量正相关,第2腹节高与体质量负相关;OS群体体长、第2腹节长、头胸甲宽与体质量正相关,第6腹节长与体质量负相关;NS群体头胸甲长、第6腹节高与体质量正相关,头胸甲宽与体质量负相关;G2群体头胸甲长、全长与体质量正相关,体长与体质量负相关。4个群体的多元回归方程经方差显著性检验均达到极显著水平(P0.01),且复相关指数均0.85,表明头胸甲部位在凡纳滨对虾良种选育中占重要地位。

Effects of Morphometric Traits on Body Weight in Different Groups of Pacific White Leg Shrimp Litopenaeus vannamei

One‐way ANOVA ,path analysis ,and multiple regression analysis were applied to analyze 24 morphometric traits including carapace length (L1 ) ,length of the first to sixth abdominal segment (L2 —L7 ) ,telson length (L8 ) ,body length(L9 ) ,total length(L10 ) ,carapace width (W1 ) ,width of the first to sixth abdominal segment (W2 —W7 ) ,carapace height (H1 ) ,and height of the first to sixth abdominal seg‐ment (H2 — H7 ) to distinguish the morphological variation in 4 groups ,V101 ,OS ,NS ,and G2 ,of Pacific white leg shrimp Litopenaeus vannamei and to find the main morhometric traits significant affecting body weight(m) .The results showed that there were significantly morphological variation in the morphometric traits in the 4 different groups (P<0 .05) ,with slender type in V101 and G2 and high fat type in OS and NS .The correlation analysis ,path analysis and degree of determination analysis revealed that carapace length and carapace height had positive effects on body weight and that the second pleopod height had a negative effect on body weight in V101 .In OS ,the body length ,the second pleopod length and carapace width were found to be positive and the sixth pleopod length negative .For NS ,carapace length and the sixth pleopod height were positive ,but carapace width was negative .For G2 ,carapace length and total length were positive ,but body length was negative .The 4 regression equations between body weight and morphometric traits were expressed at very significant level (P<0 .01) and all the multiple correlation in‐dices were greater than 0 .85 ,indicating that the major morphometric traits affecting body weight are found .The findings indicate that the major morphometric traits affecting body weight were different in the 4 groups ,and that morphometric traits for selection should be considered at different populations .