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

Abstract:

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.