两种三疣梭子蟹(Portunus trituberculatus)养殖塘中浮游细菌的季节变化

The Seasonal Variations of Bacterioplankton in Two Types of Ponds of Portunus trituberculatus

中文摘要:

      结合基于细菌16S rRNA基因的T-RFLP技术与克隆测序技术，对象山港三疣梭子蟹、脊尾白虾混养模式下改良塘M1(塘底铺网四周铺砂)以及传统塘M2(土塘)水体不同季节细菌群落结构和多样性进行分析。结果显示，M1、M2养殖塘水体细菌群落主要由变形纲门(Proteobacteria)、拟杆菌门(Bacteroidetes)、放线菌门(Actinobacteria)、蓝藻门(Cyanobacteria)组成。养殖过程中，细菌群落结构随时间发生了显著变化，不同养殖塘水体细菌群落结构变化的方向不同。M1养殖塘水体由放线菌门主导的群落结构向蓝藻菌门以及变形菌门主导的群落结构发展，M2养殖水体由蓝藻菌门主导的向变形纲门主导的群落结构发展，说明养殖后期改良塘水体有利于蓝藻细菌的生长。无论是M1还是M2，拟杆菌门在8-9月含量最高，且养殖过程中在M2水体的含量始终高于M1。随着养殖时间的推移，M1养殖塘水体细菌群落由多样性指数高的稳定性结构向多样性指数低的不稳定性结构转变，而M2水体养殖后期仍保持较高的多样性指数。PCA分析结果显示，M1养殖塘水体细菌群落差异性大于M2，说明M2水体细菌群落对环境变化的抵御能力大于M1。相关性分析结果显示，不同养殖塘水体细菌群落分布受环境的影响效应不同。

英文摘要:

      The dynamic changes and diversity of bacterial communities in two types of ponds (M1: pond with sand around and netted bottom, M2: traditional soil pond) of Portunus trituberculatus- exopalaemon carinicauda polyculture in different seasons were investigated by the technology of terminal restriction fragment length polymorphism (T-RFLP) analysis based on bacterial 16S ribosomal RNA gene and cloning. The results showed that the bacterial communities in both M1 and M2 consisted of Proteobacteria, Bacteroidete, Actinobacteria, and Cyanobacteria. The composition of bacteria community changed dramatically with breeding time with various compositions in different ponds. The bacterial community in M1 is composed of Actinomycetes, Cyanobacterium and Proteobacteria, while the bacterial community in M2 included Cyanobacterium and proteobacteria, indicating that M1 was conducive to the growth of Cyanobacteria. The highest relative abundances of Bacteroidetes were in August and September in both M1 and M2, and M2 always has higher relative abundances of Bacteroidetes than M1 during the whole farming time. The bacterial community of M1 pond changed from high diversity index and stability structure to low diversity index and instability structure over breeding time, while bacterial community of M2 pond remained high diversity index in the late breeding time. PCA analysis showed that the seasonal variations of bacterioplankton were much more obvious in M1 than M2, indicating the greater ability of M2 to resist environmental change than M1. Correlation analysis results indicated that environmental factors have different effects on bacteria community of each pond water.