Investigation Of Bacteria Diversity In Portunus Trituperculatus Rearing Pond

Bacteria are largely responsible for the process of material recycle,energy flow,ecological balance and environment purification in Portunus trituperculatus rearing pond.Bacteria have a straight relationship with the Portunus trituperculatus diseaset. In order to study the relationship between the disease outbreak and distribution of bacteria in aquaculture environment, the quantity and composition of bacteria was investigated from water column of Meishan Portunus trituperculatus rearing pond in October.Bacteria diversity was investigated in rearing environment of Portunus trituperculatus by means of the characteristics of morphology of colony,PCR,DGGE(denaturing gradient gel electrophoresis) and other modern molecular biology technology. A total of 240 strains of bacteria were isolated and purified from rearing environment of Portunus trituperculatus by serially plate dilution, and primary clustered into 15 groups based on colony characteristics, and 31 subgroups on cell characteristics, Further research was focused on the subgroups of them, which were analyzed using PCR-DGGE molecular fingerprinting techniques.And DGGE molecular fingerprinting databank of them were established. A part of 16S rRNA gene sequences (about 750 bp from 5'end) of 73 representative isolates were determined and phylogenetically analyzed. The successions of bacteria community were found in different genus or species between Bacillus, Vibrio, Halobacillus and Stenotrophomonas. Lastly, the H2S-produing bacteria,the phosphorous-cycling bacteria andnitrogen-cycling bacteria in subgroups were investigated. Metabolism of sulfur compounds which yield H2S, nitrate reduction and degradation of organic phosphorus compounds are key members of the Vibrio bacteria. Bacillus is a reduction of nitrite and degradation of key members of inorganic phosphorus. Many kinds of lyoenzymes the strain, mainly by Vibrio, Stenotrophomonas and Bacillus is primarily...