鳜回交子代与亲本子代间体型和体斑特征比较

Comparison on morphology and body spots characteristics between backcross progenies and their parents of mandarin fish

体型和体斑是鳜鱼育种的重要性状。该研究利用多重比较、杂种指数、主成分分析、判别分析对鳜回交子代[斑鳜(Siniperca scherzeri)♀×杂交鳜(斑鳜♀×鳜S.chuatsi♂)♂]与其亲本(斑鳜、杂交鳜)进行了可量形态性状差异分析,并对回交子代体斑进行了观察。结果显示,回交子代平均杂种指数为38.73,多重比较和杂种指数表明,回交子代体型偏向斑鳜。主成分分析和判别分析表明,回交子代与斑鳜、杂交鳜间的差异性状主要表现在头部隆角、体高/体长、头高/头长、C(隅骨后端至腹鳍起点长)/体长。回交子代、斑鳜与杂交鳜在前3个主成分的三维空间分布上不重叠,相互区分;判别分析可在二维空间上对3个群体进行区分。回交子代体斑主要包括背部鞍状斑与体侧斑纹,可分为4种组合类型,其中45.5%个体具有与斑鳜类似的背部鞍状斑,72.8%个体具有空心斑。研究结果可为鳜鱼回交育种研究与子代鉴定提供基础资料。

Since morphology and body spots characteristics are important breeding traits in mandarin fish crossbreeding,we analyzed the difference in quantifiable morphological traits of the backcross progeny[S.scherzeri♀×(S.scherzeri♀×S.chuatsi♂)]and parental offspring(S.scherzeri,S.scherzeri♀×S.chuatsi♂)by multiple comparison,hybrid index,principal component analysis and discriminant analysis,and observed the body spots of the backcross.The results show that the average hybrid index of the backcross was 38.73.The morphometric difference analysis and hybrid index indicate that the backcross progenies were biased toward S.scherzeri.Principal component analysis and discriminant analysis reveal that the main differences lay in head angle,body height/body length,head height/head length,and C(the length from the back of the angle bone to the beginning of the ventral fin)/body length between the backcross progenies and their parents.The three-dimensional spatial distribution of the backcross,S.scherzeri and the hybrid on the first three principal components did not overlap and were distinguished from each other.Discriminant analysis can clearly classify the three groups in two-dimensional.The body spots of the backcross included back saddle spots and trunk spots which can be classified into four different combinations.45.5%of the individuals had back saddle spots,and 72.8%had hollow spots.The results can provide data for cross breeding and hybrid identification of mandarin fish.