Pyramiding of growth-related genotypes in generations of the largemouth bass,Micropterus salmoides,‘Youlu No.1’

【Objective】Eight molecular markers related to growth traits were detected in the different breeding populations of largemouth bass, which had been found by previous studies. This would provide useful information for the actual application of limited growth markers in gene pyramiding breeding of largemouth bass.【Method 】 Using the technology of STR genotyping, genotype of 8 growth markers in the F2, F3, F5 and F6 generations of largemouth bass (Micropterus salmoides),‘Youlu No.1’ were detected and the number of advantage genotypes was analyzed. The growth markers included four sites of single nucleotide polymorphism located in IGF-I, POU1F1, PSS Ⅲ and MSTN gene and four sites of microsatellite: JZL60, JZL67, MisaTpw76 and MisaTpw117.【Result and conclusion】 The number of advantage genotypes was 0-6 in the tested fishes. The average number was 2.12, 2.70, 2.90 and 3.08 in F2, F3, F5 and F6 generations, respectively, presenting an increasing trend with each generation. The number of the advantage genotypes increased synchronously with the growth rate of the breeding largemouth bass in different populations. This means that the artificial selection has polymerized the advantage genotype to some extent.