建鲤与黄河鲤的杂交优势研究及主要生长性状的通径分析

通过比较建鲤Cyprinus carpiovar.及其与黄河鲤Cyprinus carpio haematopterus正反杂交子代的体长、体高、体重、生长指标、丰满度、变异系数以及杂交F1的超亲优势率,建立了其生长方程,并对主要生长性状进行了通径分析。结果表明:反交F1在体长、体重和生长指标方面具有明显优势,生长和增重最快,其变异系数也最大,需加强选育;建鲤的丰满度始终较高;反交F1在体长、体重上的超亲优势率均高于正交F1。通径分析结果表明:子代的体长、体高、体重间均呈显著正相关;体长对体重的影响主要为直接效应,而体高对体重的影响主要为间接效应;体长、体高的效应在建鲤中差异不明显,而在杂交F1中,体长的效应远大于体高;剩余项的决定系数很小,说明体长和体高在影响体重的增长方面具有决定性作用。

The heterosis of F1 hybrids (jian carp × huanghe carp) and path analysis of main growth traits

Comparison between the F1 hybrids(direct cross and reciprocal cross) of Jian carp(Cyprinus carpio L.),and Huanghe carp(Cyprinus carpio haematopterus) and Jian carp were made on the body length,body height,body weight,growth index,fullness,variation coefficient and super-parents heterosis.Growth equations were established and path analysis of main growth traits were conducted.The results showed that reciprocal cross F1had significant heterosis in terms of body length,body weight,and growth index owing to the fast growth and increment.But the high degree of variation coefficient suggested an intensive selection be needed.The highest fullness was observed in Jian carp all the time.There was higher super-parents heterosis rate on body length and body weight in reciprocal cross F1 hybrids than that in direct cross F1 hybrids.Path analysis revealed that body length and body height were closely related with body weight in offspring.The influence of body length on body weight was attributed to the direct effect while the influence of body height on body weight resulted from indirect effect.There was no difference between body length and body height effect in Jian carp.However,in F1 hybrids,the effect of body length was much higher than that of body height.The decisive coefficient of remnants was negligible,indicating that body length and body height had the decisive effect on weight increment.