广西鲤鱼选育F_2代家系育种效果分析

【目的】分析评估广西鲤鱼选育F_2代家系选育效果,为培育适合广西本地养殖的鲤鱼新品种打下基础。【方法】采用最佳线性无偏差预测法(BLUP)对60个F_1代家系的育种值进行评估,构建获得71个F_2代选育系(A1~A71)和20个对照系(B1~B20),经被动整合应答标记法(PIT)标记后同塘混养320 d,然后进行F_2代家系生长性状测定,并对其体质量遗传增益效果及各性状现实遗传力进行初步估算。【结果】F_2代选育系和对照系的平均体质量分别为1008.5和911.9 g,平均日增重3.1和2.8g,瞬时增重率分别是1.18和1.15%/d,选育系的生长速度比对照系遗传增益10.6%,二者差异显著(P0.05,下同);其全长、体长和体高也有显著提高。F_2代选育系的体质量、全长、体长、体高、体宽现实遗传力分别为0.25、0.33、0.22、0.27和0.15,属于中等遗传力。从获得的71个F_2代选育系中选出成活率在60.0%以上、平均体质量超过1100.0g的7个F_2代家系进行生长性状参数分析,结果发现A54和A35两个F_2代家系是所有家系中生长性状较优良的家系。【结论】广西鲤鱼选育F_2代家系育种效果明显,其中A54和A35两个家系不但生长速度快,而且体型较长、生长整齐,具有较大的选育潜力,可作为下一代选育的后备亲本,为繁育场提供优良的鲤鱼种苗。

Breeding effects of Cyprinus carpio F2 generation pedigrees in Guangxi

Obiective]The present study was conducted to evaluate breeding effects of Cyprinus carpio F2 generation pedigrees in Guangxi in order to lay a foundation for breeding new C. carpio varieties that are suitable for local environment.Method]Best linear unbiased prediction(BLUP) was adopted to evaluate breeding values of 60 F1 pedigrees. 71 F1 generation selected strains(A1-A71) and twenty control families(B1-B20) were selected. These strains were marked with passive integrated transponder(PIT) and cultured in the same pool for 320 days. Growth traits of F2 generation pedigrees were measured later, and their body weight genetic gains and realized heritabilities were estimated. Result]Average body weight of F2 generation selected strains and control families were 1008.5 and 911.9 g, average daily gains were 3.1 and 2.8 g, instantaneous growth rates were 1.18%and 1.15%/day, respectively. Growth speed of selected strain was 10.6%higher than that of control family, and the difference was significant(P<0.05, the same below). Full length, body length and body height of selected strain increased significantly compared with those of control family. Realized heritabilities of body weight , full length, body length, body height and body width in F2 generation pedigrees were 0.25,0.33,0.22,0.27 and 0.15, re-spectively, belonging to medium heritability. By analyzing seven F2 generation pedigrees selected out of seventy-one F2 generation pedigrees whose survival rates were above 60.0% and average body weight exceeded 1100.0 g, A54 and A35 were identified as two superior F2 generation pedigrees with sound growth traits among all pedigrees. Conclusion]Breeding effect of C. carpio F2 generation pedigree is obvious. A54 and A35 are two superior pedigrees with fast growth speed, long body length and synchronous growth. The two pedigrees boast great potential for breeding, and can be used as backup par-ents of next generation of breeding, and provide improved C. carpio fries for breeding field.