Abstract
Pampus argenteus, a commercially significant marine species, faces genetic diversity challenges in selective breeding programs. This study implemented a comprehensive molecular strategy to evaluate genetic parameters in wild populations along China's coast and three successive selected generations. The analysis utilized 19 highly polymorphic microsatellite loci, mtCOI, and mtD-loop sequences to assess genetic structure. Compared with the wild populations, the average number of alleles (N(a): 11.158-12.947), effective alleles (N(e): 5.592-6.502), observed heterozygosity (H(o): 0.626-0.665), expected heterozygosity (H(e): 0.777-0.796), and allele richness (A(r): 10.900-12.510) of the selected populations did not significantly decrease. In the mass selection of the three consecutive generations, the high genetic diversity of the selected population was successfully maintained. The effective population sizes of the first to third generations were estimated to be 83.7, 66.6, and 59.6, respectively. Population differentiation analysis showed minimal genetic divergence (FST = 0.0159-0.0326) with substantial gene flow, supported by clustering patterns indicating panmixia among wild populations from different geographical locations and among the selected populations. Notably, marginal decreases in diversity indices across generations suggest incipient genetic diversity decline, underscoring the imperative for systematic genetic monitoring. These findings validate the current breeding program's efficacy in maintaining genetic variability while providing a framework for optimizing long-term selection strategies to prevent inbreeding depression.