4种笛鲷属鱼类随机扩增多态性DNA及遗传多样性研究

使用RAPD技术分析了红鳍笛鲷、紫红笛鲷、勒氏笛鲷和约氏笛鲷的种内遗传多样性、种间遗传多样性和种间亲缘关系。在120个随机引物中筛选出扩增效果好的引物36个，平均每个引物在每个个体上产生7．7个条带。种内遗传多样性研究结果显示：遗传距离(D)分别为0．2257，0．2228，0．2679和0．2247；遗传多样性指数(H)分别为0．1854，0．1904，0．2015和0．1865。说明目前湛江近海这4种笛鲷的遗传多样性比较丰富，它们的种质资源仍处于一个良好的水平。种间遗传多样性结果显示：勒氏笛鲷与约氏笛鲷遗传距离(Dpq)最小，亲缘关系最密切，勒氏笛鲷与红鳍笛鲷种间Dpq最大，亲缘关系最远。

RAPD Analysis of Four Snapper Species

The genetic diversity, relationship and species-specific markers were detected in four snapper species, Lutjanus johni, Lutjanus russelli, Lutjanus erythopterus and Lutjanus argentimaculatus, by random amplified polymorphic DNA(RAPD). A total 120 random primers were evaluated for their usefulness in the snappers. Of the 120 primers, 36 ones were useful according to the quantity, quality and reproducibility of loci. Each of the 36 primers produced 7.7 bands on average in one sample. The intra-species diversity showed that the mean genetic distance of intra-species (D) was 0.2257, 0.2228, 0.2679 and 0.2247, respectively, and the genetic diversity index of intra-species (H) was 0.1854, 0.1904, 0.2015 and 0.1865, respectively. These data indicate that high levels of genetic variation exist in each species, which suggest that the activity of aquaculture has not caused reduction in genetic diversity of these snappers. The inter-species diversity analysis indicates that the L. russelli is the closest to L. johni, While L. russelli is the farthest to L. erythopterus. Still, 8 species-specific markers, which can be used as molecular genetic markers, were found.