两种青岛沿岸常见江蓠科物种室内培养过程中附生菌群的组成及其变化分析

Analysis of the Composition and Changes of Epiphytic Flora in the Indoor Culture of Two Common Species of Gracilariaceae at Qingdao Coast

为了探究青岛沿岸两种常见江蓠科物种(真江蓠(Gracilaria vermiculophylla)和龙须菜(Gracilariopsis lemaneiformis))在室内培养后生长状态不如野生状态是否是因为附生菌群发生变化。本研究中首先对16S rDNA特异引物对(799F-1392R)在真江蓠和龙须菜中的适用性进行了评估,之后采用16S rDNA测序法对真江蓠及龙须菜的附生菌群落多样性、群落结构组成及其变化进行分析。研究结果显示,引物对(799F-1392R)能够避免真江蓠和龙须菜叶绿体基因序列的干扰,并能与其附生菌16S rDNA高效结合;野生与室内培养的江蓠附生菌群落存在差异,与野外生长的江蓠附生菌群落相比,室内培养的江蓠附生菌群落丰富度更低,且随着培养时间的延长,附生菌的组成门类逐渐减少。真江蓠与龙须菜间的附生菌群落组成也存在差异,不同的附生菌对这两种江蓠偏好不同。研究结果表明,室内培养环境与野生环境的巨大差异是造成附生菌组成变化的主要原因,而物种的化学组成差异也导致两种江蓠表面附着不同的细菌。本研究为扩展藻菌关系的认知和优化藻类室内培养条件提供了理论支持。

The growth status of macroalgae collected in the wild is often not as good as that in the wild after a period of indoor cultivation.To answer the question whether the composition and number of the epiphytic flora would change during this progress,two closed related species in Gracilariaceae,Gracilaria vermiculophylla and Gracilariopsis lemaneiformis were collected from Qingdao coast.These two species shared similar morphology and distributed nearly.The bacteria compositions and changes were analyzed and compared for these two macroalgae species during the 90 days indoor cultivation.Firstly,the study evaluated the suitability of 16S rDNA specific primers(799F-1392R)for analyzing the epiphytic flora of Gracilaria vermiculophylla and Gracilariopsis lemaneiformis.The primer pair 799F-1392R was found to be effective in avoiding interference from the chloroplasts of these algae,enabling a smooth analysis of the flora structure.Next,16S rDNA sequencing was used to analyze the community diversity,community structure,and changes in the epiphytic flora of Gracilaria vermiculophylla and Gracilariopsis lemaneiformis.The results revealed differences between the epiphytic flora of the algae in their natural habitat and those cultured indoors.The richness of the epiphytic flora was lower in the indoor culture of Gracilariaceae compared to the wild environment.Additionally,there were differences in the composition of epiphytic flora between Gracilaria vermiculophylla and Gracilariopsis lemaneiformis,with various types of epiphytic flora showing different preferences for these two species of Gracilariaceae.The study suggested that the enormous differences between the indoor and natural environments might be the main reason for the changes of epiphytic flora.Furthermore,the variation in chemical composition between the two Gracilariaceae species also influenced the bacteria attached to their surfaces.Overall,this study provides theoretical support for enhancing our understanding of the relationship between algae and bacteria,as well as optimizing the indoor culture of algae.