杂色鲍幼体附着基藻际细菌群落的PCR-DGGE分析

Analysis of the bacterial community in the phycospere of the attachment substances of larval abalone(Haliotis diversicolor Reeve) by PCR-DGGE

附着基是苗期杂色鲍（Haliotis diversicolor Reeve）生活的主要场所，其表面藻际细菌对幼体的生长有重要的影响，然而对附着基藻际细菌多样性的研究较为少见。本研究在杂色鲍育苗期间定期采集附着基样品，再利用PCR．DGGE技术对藻际细菌群落进行多样性及变化规律分析。相似性和UPGMA聚类结果表明，藻际细菌群落结构随时间变迁呈现出连续性变化，相邻两天细菌群落的戴斯相似性系数G高达80．9％～96．1％，但育苗前期与育苗后期的藻际细菌群落组成差异较大。多样性指数分析显示，育苗前期藻际细菌多样性随时间变化趋于丰富，之后多样性稍有下降但仍维持较高水平。受附着基上藻类生长状况及鲍摄食活动等因素的影响，细菌多样性指数出现一定波动。本研究旨为鲍的科学育苗与健康养殖提供理论参考，为进一步深入研究环境变化与鲍苗期细菌性病害的关系打下良好基础。

The attachment substances are used by larval abalone （Haliotis diversicolor Reeve） during their early ontogeny. The bacteria in the phyeospere on the surface of the attachment substance has a significant impact on the growth of the larvae. Up to now, little is known about the bacterial diversity in the phycospere on the adhering substance. We collected the attachment substance from seedling Haliotis diversicolor Reeve and analyzed the bacterial community diversity and variation in the phycospere by PCR-DGGE. The bacterial community structure in the phycospere changed over time. Although there was considerable similarity in the community between adja- cent days （Dice coefficient Cs： 80.9%-96.1%） there was a significant difference between early stage and late stage seedlings. Analysis of the diversity index revealed an increase in the richness of the bacterial diversity of the phycospere in early stage seedlings, and diversity was maintained thereafter. The bacterial diversity index re- mained within a given range because of the influence of algae growth and abalone feeding activity. Our results provide a theoretical basis for scientific breeding and healthy aquaculture of abalone, and lay a foundation for further study of the relationship between environmental changes and bacterial diseases of larval abalone.