两种石斑鱼及其杂种子代的分子鉴定

针对在分类上存在混淆的点带石斑鱼和斜带石斑鱼,在形态学基础上,运用mtDNA Cytb基因扩增序列分析、RAPD、AFLP等分子标记技术对两种石斑鱼的遗传关系进行了研究.研究结果表明:(1)点带石斑鱼与斜带石斑鱼的分化已达到种间水平,mtDNACytb基因序列相似度为94.4%,AFLP扩增片段的遗传相似率为0.7539;(2)两种石斑鱼存在杂交现象,RAPD、AFLP的扩增谱图中均获得亲本与子代的特异性条带,父本对杂交子代的遗传影响略大于母本;(3)AFLP标记在点带和斜带石斑鱼及其杂交子代中的遗传符合孟德尔遗传规律,可用于构建两种石斑鱼的遗传连锁图谱.研究结果将对两种石斑鱼种质资源的保护及人工繁育的可续性提供重要参考.

The identification of Epinephelus malabaricus and E.coioides based on DNA markers

Using multi-molecular marker technology and based on morphological criteria,the genetic relationship between E.malabaricus and E.coioides was examined in the hope of resolving the longstanding issue of identifying of these two species.Results showed that:(1) E.coioides and E.malabaricus should be identified as two species,the consistency of mitochondrial DNA cytochrome b gene sequence between E.malabaricus and E.coioides is 94.4%,the genetic similarity by AFLP was 0.753 9;(2)hybridization exists between E.malabaricus and E.coioides,the specific RAPD and AFLP fragments are found to be useful in the identification of these two species,the genetic properties(both with exterior and inheritance) of hybrid is significantly biased to the male parents;and(3)AFLP was a potentially powerful tool in constructing genetic linkage map for these two groupers.