Abstract:

This paper analyzed the bacteria community composition and variation of seawater from culture ponds of Apostichopus japonicus at Wafangdian, Dalian City, Liaoning Province. Seawater of different periods from culture ponds of Apostichopus japonicus was collected, and variable region fragments of 16S rDNA V3 were amplified by specific primers of bacteria, and analyzed with deformation gradient gel electrophoresis (DGGE). The main bands were cut, recovered, and sequenced. The results showed that the diversity index of samples from different periods varied from 1.994 5 to 2.230 5, and there were not big differences in evenness. The sample richness was between 42 and 48. But there were differences between bacterial community compositions of those samples. In March and September seawater shared the highest similarity(80%), and in June and other months, there was the biggest difference in cluster distance. Results of 39 main bands of sequences indicated that 12 bands of them were close to uncultured bacteria, 1 band was close to Actinobacteridae, and 26 bands were identified as Flavobacteria, α-proteobacteria and γ-proteobacteria. Flavobacteria, α-proteobacteria and γ-proteobacteria appeared in seawater at all periods, and among them Flavobacteria was dominant with proportion of 23.8%~50.0%. Seawater bacterial community compositions in cultured ponds at different periods were relatively stable, but there were differences in specific strains.

Key words: Apostichopus japonicus, PCR-DGGE, seawater from culture pond, bacterial community

摘要：

对辽宁省大连市瓦房店刺参养殖池塘海水菌群结构组成和变化情况进行分析，采集不同时期刺参养殖池塘海水，扩增细菌16S rDNA基因V3可变区序列，进行变性梯度凝胶电泳（DGGE），分析指纹图谱，并对主要条带进行切胶、回收和测序。结果表明，不同时期海水各样品的多样性指数在1.994 5~2.230 5之间，均匀度差异不大，样品的丰富度在42~48之间。不同时期海水中3月和9月的菌群结构最为相近（80%），6月与其他各时期聚类距离最大。对39个主要条带的测序结果表明，12个条带与未培养细菌相近，1个条带与放线菌纲（Actinobacteridae）的菌株相似，另外26个条带相似菌株分别归类为黄杆菌纲（Flavobacteria）、α-变形菌纲（Alpha proteobacteria）、γ-变形菌纲（Gamma proteobacteria）。黄杆菌纲、α-变形菌纲和γ-变形菌纲在各时期海水中均有出现，其中黄杆菌纲优势度最高，占23.8%~50.0%。不同时期养殖池塘海水菌群的结构相对稳定，但具体菌种存在差异。

关键词: 刺参；PCR-DGGE；养殖池塘海水；细菌菌落