杂交石斑鱼(斜带石斑鱼♀×赤点石斑鱼♂)与其亲本形态性状比较研究

研究了杂交石斑鱼斜带石斑鱼(Epinephelus coioides)♀×赤点石斑鱼(E.akaara)♂]与其亲本的生长差异。采用形态学测量方法,分别测定了3种石斑鱼体质量和7个形态性状,对各形态性状对体质量影响进行通径分析,并分析杂交子代杂种优势。结果显示,3种石斑鱼各形态性状与体质量之间均呈极显著相关(P0.01),斜带石斑鱼、赤点石斑鱼体质量与全长的相关性最高,相关系数分别为0.946、0.932,杂交子代体质量与尾柄高的相关性最高(0.955),与全长的相关系数为0.927;形态性状与体质量的多元线性回归方程中,斜带石斑鱼保留体长、体高、尾柄高和体厚,赤点石斑鱼保留全长、体高和尾柄高,杂交子代保留全长、体高、尾柄高和体厚。对杂交子代杂种优势进行分析发现,体质量平均杂种优势为3.43%,体长平均杂种优势为3.02%,杂交子代同时表现出正向超亲优势和负向超亲优势。该研究表明杂交子代(斜带石斑鱼♀×赤点石斑鱼♂)与斜带石斑鱼的差异要小于赤点石斑鱼,杂交子代形态性状更偏向于母本。

Comparison of morphological traits of hybrid groupers (Epinephelus coioides ♀ × E.akaara ♂) and their parents

We measured the body mass and seven morphometric traits of hybrid groupers (Epincphelus coioides ♀ × E.akaara ♂) and their parents to analyze the relationship between morphometric traits and body mass using path analysis,and then obtained multivariate regression equations.The results show that the correlation coefficients between body mass and morphometric traits have very significant difference in all three groupers (P ＜ 0.01).The total length and body mass had the highest correlation coefficient both in E.coioides and E.akaara,being 0.946 and 0.932,respectively.But for hybrid groupers,the highest correlation coefficient was between caudal peduncle depth and body mass (0.955),and the correlation coefficient between total length and body mass was 0.927.The multivariate regression equation of E.coioides retained standard length,body height,caudal peduncle depth and body width.The multivariate regression equation of E.akaara retained total length,body height and caudal peduncle depth.The multivariate regression equation of hybrid groupers retained total length,body height,caudal peduncle depth and body width.The analysis of heterosis in hybrid groupers found obvious average heterosis,while the negative (compared with male parents) and positive (compared with female parents) heterobeltiosis were found in hybrid groupers.The average heterosis of hybrid groupers in body mass and standard length were 3.43％ and 3.02％,respectively.It is revealed that the difference between hybrid groupers and female parents is less than the difference between that and male parents,and the hybrid groupers resemble female parents in morphological traits.