The genetic diversity of both wild and reared Pseudosciaena crocea (Richardson) col-lected from Guan-Jing-Yang in Ningde, China in May 1999 was investigated by random amplified poly-morphic DNA (RAPD) in the present study. The polymorphism and mean difference of the wild popula-tion as revealed by RAPD were 18.9% and 0.0960 respectively, and those of the reared stocks were rel-atively lower, with 16.7% in polymorphism and 0.0747 in mean difference. The genetic distance be-tween the two stocks was 0.0041. From the comprehensive investigation, the main reasons for the loss of genetic diversity were probably overfishing, small number of parents as broodstocks and the debatable arti-ficial ranching. Results from this study also showed that the large yellow croaker populations distributed a-long Fujian coastal waters including Guan-Jing-Yang still potentially wide genetic variability. It is suggest-ed that genetic management and prevention should be scientifically conducted in order to maintain and im-prove the genetic diversity of the P. crocea population.

采用一对特定引物对形态相近的单殖吸虫新贝尼登虫新贝尼登虫的基因组DNA进行PCR扩增，获得其28S rRNA 的350 bp左右的特异片段。测序后经软件分析发现两者同源的337bp 序列仅存在一个碱基的差异，遗传相似度达99.70%，甚至高于不同海区不同宿主梅氏新贝尼登虫间99.41%的相似度，与贝尼登虫属3个虫种的同源序列间的遗传差异度为2.08%～11.73%。通过UPGMA和MP聚类分析也可看出，新贝尼登虫和梅氏新贝尼登虫的遗传相似性是极为相近的。虽然两种新贝尼登虫的形态特征和遗传多样性极为相似，但它们是否同属于一个种还不能确定，需要经进一步的形态系统比较和更多的基因分析才能得出客观的、公认的结果。