草鱼生长相关优势基因型的聚合效果分析

The effects of pyramiding growth-related genotypes in grass carp (Ctenopharyngodon idella)

中文关键词: 草鱼  生长性状  分子标记  优势基因型  基因聚合

英文关键词: Grass carp  Growth traits  Molecular marker  Advantage genotype  Pyramiding

中文摘要:

      为研究草鱼(Ctenopharyngodon idella)生长性状相关分子标记聚合效果，本研究选择利用候选基因关联分析方法获得10个与生长性状相关SNP标记，分别位于草鱼载脂蛋白A-I-1基因(apoA-I-1)、丙酮酸激酶1型(PKL)、羧肽酶A1 (CPA1)、柠檬酸合酶(CS)、醛缩酶B(Aldo-B)、生长催乳素α (SLα)和肌球蛋白重链(MYH)基因上。先在24尾雌鱼和24尾雄鱼亲本中对各标记进行基因型检测，挑选1对最有利于不同优势基因型发生聚合的亲鱼构建家系。在7月龄时，对子代进行生长性状测量和各SNP标记的基因型分型，采用一般线性模型分析含不同优势基因个数的组别生长差异。结果显示，家系子代个体中含生长相关优势基因型的数量为0、1、2、3、4、5、6、7个，对应的个体数量依次为44、67、83、85、44、38、15和6尾，对应的平均体质量依次为129.66、144.45、151.33、153.53、154.77、160.50、167.50和176.67 g，生长相关优势基因型的聚合个数与草鱼生长速度呈正相关。子代中优势基因型的平均数量为2.58，与亲本群体的优势基因型平均数量(1.00)相比显著提高。研究表明，对草鱼生长相关优势基因进行聚合可获得生长性状优良个体，为草鱼分子标记辅助育种应用提供理论依据。

英文摘要:

      To better understand the effects of pyramiding advantageous genotypes of the growth-related molecular markers in grass carp (Ctenopharyngodon idella), ten molecular markers related to growth traits were selected from our previous studies, located in apoA-I-1 (apoprotein A-I-1), PKL (pyruvate kinase L), CPA1 (carboxypeptidase A1), CS (citrate synthase), Aldo-B (aldolase-B), SLα (somatomammotropin-α), and MYH (myosin heavy chain). The genotype of each marker in forty-eight grass carp was analyzed, and two parents with the most advantageous pyramiding genotypes were selected to create a family. Seven-month-old individuals (n=382) were randomly sampled from the second filial generation. The results showed that the number of advantageous genotypes varied (0~7), and the corresponding number of individuals was 44, 67, 83, 85, 44, 38, 15, and 6. The average weight of the advantageous genotypes was 129.66, 144.45, 151.33, 153.53, 154.77, 160.50, 167.50, and 176.67 g. Correlation analysis showed that the pyramiding number was positively correlated with the growth traits. Further analysis showed that the average number of advantageous genotypes was 2.58, which was improved compared to the average number in the parent group (1.00). These results indicate that the growth traits of grass carp can be improved by aggregating the advantageous genotypes. This study also provides a theoretical basis for gene pyramid breeding in grass carp.