侧孢短芽孢杆菌溶藻活性代谢产物对虾池颤藻的溶藻效果

Research on algicidal effect of bioactive metabolites of Brevibacillus laterosporus on Oscillatoria sp.in shrimp pond

为改善对虾养殖水环境,研究了不同阶段的侧孢短芽孢杆菌无菌滤液和颤藻对溶藻效果的影响。通过测定溶藻过程中藻体干重、叶绿素a含量以及藻蓝蛋白含量,探究了溶藻效果的最佳作用阶段及其作用机理。结果显示,稳定期和衰亡期的无菌滤液对颤藻的溶藻效果极为显著,7 d后颤藻干重分别减少了51.77%、47.04%,叶绿素a含量分别降低了67.60%、59.13%,藻蓝蛋白含量分别增加了33.51%、30.97%;溶藻细菌无菌滤液对延滞期颤藻的溶藻效果极显著,7 d后颤藻干重减少了63.90%,叶绿素a含量下降了69.72%,藻蓝蛋白含量升高了54.17%。结果表明,侧孢短芽孢杆菌培养至稳定期的无菌滤液对延滞期颤藻的溶藻效果最好。

Oscillatoria sp. is a common and harmful cyanophyte in shrimp culture pond. In this study, the sterile filtrate of Brevibacillus laterosporus and Oscillatoria sp. were used to study the algicidal effects in their different growth stages. The algae dry weight,chlorophyll-a and phycocyanin content were measured in order to explore the best algae-lysing period and the algicidal mechanism. The final aim was to provide the basic theory for improving water environment in shrimp pond. The results showed that algicidal effects of the sterile filtrate on Oscillatoria sp. were very significant（P 〈 0.01 ） when the algae-lysing bacteria was in the stable and decline phases. After 7 days, the algae dry weights were reduced by 51. 77% , 47. 04% respectively, the contents of chlorophyll-a were decreased by 67. 60%, 59. 13% respectively; the phycocyanin contents were increased by 33.51% ,30.97 % , respectively. Similarly, the algicidal effect of the sterile filtrate of algae-lysing bacteria was so conspicuous （P 〈 0.01 ） on the lag phase Oscillatoria sp.. 7 days later,the algae dry weight was reduced by 63.90% ;the content of chlorophyll-a was decreased by 69. 72% ;the phycocyanin content was increased by 54. 17%. The conclusion was that the sterile filtrate of Brevibacillus laterosporus in the stable phase had the best algicidal effect on the lag phase Oscillatoria sp..