# Genetic Structure and Optimal Population Size of Wild and Mass-Selected Silver Pomfret (Pampus argenteus) in China: The Implications for Conservation and Selection Breeding Programs

## TL;DR

This study examines the genetic health of selectively bred and wild silver pomfret populations in China, showing that breeding programs can maintain diversity while improving productivity.

## Contribution

The study introduces a comprehensive genetic framework for balancing selective breeding with biodiversity conservation in marine aquaculture.

## Key findings

- Selective breeding of silver pomfret maintained genetic diversity comparable to wild populations.
- Effective population sizes remained sufficiently large (59.6–83.7) across generations.
- Minimal genetic differentiation and strong gene flow suggest successful breeding strategies.

## Abstract

This study systematically evaluated the genetic structure of three consecutive generations of selectively bred and wild populations of silver pomfret (Pampus argenteus) along China’s coast. The research aimed to address potential risks of genetic diversity loss during breeding programs while concurrently investigating the threat of inbreeding depression in these populations. Using 19 newly developed, highly polymorphic genetic markers and mitochondrial gene analysis, the selected populations showed no significant reduction in genetic diversity compared to wild populations, with effective population sizes maintained within 59.6–83.7. Strong gene flow (values > 1) and minimal genetic differentiation (0.0159–0.0326) between geographical groups confirmed successful integration of high-yield trait selection with genetic diversity preservation. However, a subtle decline in diversity was observed in selected populations, underscoring the necessity for ongoing monitoring to prevent inbreeding risks. The findings provide crucial insights for genetic improvement programs. They demonstrated that well-designed selective breeding can enhance aquaculture productivity and sustain population genetic health. This work establishes a scientific framework for balancing economic important characteristics with biodiversity conservation in marine fish breeding, offering practical strategies for sustainable aquaculture development.

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 (Na: 11.158–12.947), effective alleles (Ne: 5.592–6.502), observed heterozygosity (Ho: 0.626–0.665), expected heterozygosity (He: 0.777–0.796), and allele richness (Ar: 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.