福建太平洋牡蛎种群微卫星DNA分析

Microsatellite sequence variation in the Pacific oyster Crassostrea gigas from south Fujian,China

本文采用Ucdcg153、157、202微卫星引物对福建两个太平洋牡蛎(学名为长牡蛎Crassostrea gigas)养殖种群进行扩增分析和序列测定.与采自漳浦旧镇的近江牡蛎(C. ariakensis)比较,前者对以上三种引物全部呈阳性反应,后者只对Ucdcg157显阳性.与Genebank提供的相关序列比较,福建太平洋牡蛎与Genebank样品应属同源,其中漳浦霞美和厦门白礁的样品则可能代表同一种群的两个衍生品系.本项调查结果同时显示,近亲繁殖的育苗方式已经导致福建太平洋牡蛎种群裂化;任其发展不利于维护良种优势.本次采集的样品中未发现显示葡萄牙牡蛎、熊本牡蛎和美洲牡蛎微卫星特征的个体.

In present studies, we used three microsatellite markers, i.e. , Ucdcg153, Ucdcg157 and Ucdcg202, to investigate sequence variations of two farmed populations of C. gigas from Fujian. All DNA samples from either population were well amplified in response to relevant primers. To the contrast, samples of a native cup oyster C. ariakenis failed PCR-electrophoretic inspections when exposed to primers for Ucdcg153 and Ucdcg202 loci. According to results of microsatellite sequence analyses, populations of C. gigas in Fujian should have the same origin as those which left the first sequence data for Ucdcg153, Ucdcg157 and Ucdcg202 loci in Genebank, while the present two Fujian populations, one collected from Xiamei, Zhangpu County, another from Baijiao, Xiamen, were possibly derived from one. Sequence discrimination between C. gigas from Xiamei and Baijiao revealed serious crisis of population fragmentation for C. gigas in Fujian. Inbred hatchery manipulation is considered to be responsible for this situation. No individuals of C. angulata, C. sikarnea and C. virginica were detected by microsatellite characters during this work.