环境因子对发光细菌的生长及日本对虾仔虾感染死亡率的影响

以水温、盐度、pH、COD、NH3－N为环境因子，哈维氏弧菌（Vibro harveyi)感染日本对虾（Penaeus japonicus）仔虾，试验进行3d。结果表明，水温、温度、pH和COD对发光细菌的生长和日本对虾仔虾的感染死亡率具有明显的促进作用。在水温30℃，盐度32．8，pH7．654和COD10．2mg／L时，发光细菌在试验结束时的数量比初始时分别增加了11．2倍，6．5倍和7．9倍；日本对虾仔虾的死亡率比对照组分别增加了60％，45％，43％和50％。NH3－N对发光细菌的促生长作用不明显，但其质量浓度1．2－1．6mg/L时，能增加日本对虾仔虾对发光病的感染率和死亡率。

Effects of environmental factors on growth of luminous bacteria (Vibro harveyi) and mortality of infected post-larvae of Penaeus japonicus

Water temperature, salinity, pH, COD, NH3-N were regarded as theenvironmental factors and the bacterium Vibro harveyi was used to infect Penaeus japonicus for 3 d. The results show that water temperature, salinity, pH and organic matters have obvious enhancement effect on the growth of V.harveyi and lead to higher mortality of P.japonicus with any one of the factor levels going up. When water temperature 30℃, salinity 32.8, pH 7.64 and COD 10.2 mg／L, the bacteria densities of V.harveyi at the end of the experiment is higher by 11.2, 6.5, 6.2 and 7.9 times, respectively，than those at the beginning and the mortalities of P.japonicus in the corresponding groups are increased by 60％, 45％, 43％ and 50％, respectively. NH3-N has no obvious effect on growth of V.harveyi, but when its concentration is between 1.2 and 1.6 mg／L,the mortality and V.harveyi-infected rate of P.japonicus can be heightened.