Effects Of Bdellovrio Sp Strain BDM01on The Microbial Community During The Growth Of Penacus Monodon

Bdellovibrio are predators of other bacteria and have great use of prospects to controlbacteria. Shrimp aquaculture is one of the mainstay industries in China. With the restructuringof aquaculture and sustainable development, the requirement of ecological farming is aroundthe corner. As we know the key to the success of aquaculture is water environment. Thispaper applied Bdellovibrio sp strain BDM01and/or Bacillus subtilis during the growth ofPenacus monodon. And the survival rate of Penacus monodon, bacterial concentration andchanges of bacteria group structure were discussed. This study provides reference data for thefuture study on Bdellovibrio sp.The main results are as follows:1. With Bdellovibrio sp treated only (group1), the survival rate and growth vigor of Penacusmonodon was better than that of control group and group treated with Bdellovibrio sp andBacillus subtilis(group2).2. The control of total bacteria and Vibrio concentration of group1was better than controlgroup and group2. The control of total bacteria of group2was better than control group.There was no significant difference between control group and group2on controlling ofVibrio concentration.3. Optimization of the PCR-DGGE system for aquaculture water was proved effectivelyimproved the result of DGGE: CTAB method used to extract total DNA, the conditions ofPCR was optimized, DGGE was defined to be30%-60%,200V,60℃,5hours, primer with40GC-clamp perform better effect, sample volume was10μL, and silver staining.4. The aquaculture water samples during the growth of Penacus monodon were detected bythe optimized PCR-DGGE system. Result shows that the bacterial species of the three groupsfrom largest to smallest in descending order is control group, group2, group1. With thepassage of time, the number of bands for control group increased gradually, but it wasopposite for group1and2. The bacteria group structure of group1was more stable.5. The bacteria group structure during water exchange period was detected by the optimizedPCR-DGGE system. Among the three detected period, the similarity of the two samples ingroup1was the highest. This show that the bacteria group structure of group1was more stable. Sequencing results showed that bacteria species in aquaculture water were abundantand with extensive sources and most detected bacteria were uncultured strains.