【作者】 张瑜斌； 林鹏； 邓爱英； 庄铁诚；

【Author】 ZHANG Yubin LIN Peng DENG Aiying ZHUANG Tiecheng ( School of Life Sciences, Xiamen University, Xiamen 361005, China; Institute of Aquatic Biotechnology and Environmental Resources Protection, Shantou University, Shantou 515063)

【机构】 厦门大学生命科学学院；

【摘要】 在使用稀释平板法分离潮间带红树林及其对照光滩土壤微生物以及计数时,多数情况下使用陈海水制作培养基和稀释水,很少考虑培养基和稀释水的盐度对最终计数结果的影响。本项研究中,使用稀释平板法研究了盐度对福建九龙江口红树林区土壤微生物平板计数的影响,结果表明,培养基与稀释水盐度对微生物数量有明显的影响。统计分析显示细菌的海水稀释效果优于淡水,而放线菌与真菌则刚好相反(P<0.05是一个例外)。海水不适合配制红树林区土壤微生物平板计数的培养基,从0‰～35‰,高盐度的平板培养基会降低微生物的数量,尤其是放线菌的数量,尽管真菌培养基的盐度影响不显著,但细菌数量在低盐度时比在高盐度和不加氯化钠时要多。根据盐度效应,提出了稀释平板技术应用于潮间带的红树林及其相应光滩(潮间带)时的优化方法,认为细菌应该用海水作无菌稀释水,而放线菌和真菌则应用淡水作稀释水;潮间带微生物分离与计数的培养基宜控制较低盐度范围。更多还原

【Abstract】 When isolating and quantitating the soil microbes are isolated and their numbers or densities are determined in mangroves and corresponding mudflat as contrast at the same tidal level by dilution plate method, the plate agar media and dilution water are generally made up of aged seawater in most cases. The effect of salinity in agar media and dilution water on final counting of microbes is seldom taken into consideration. The present study was designed to evaluate effect of salinity on soil microbial counting on the plates in mangrove areas in Jiulongjiang Estuary of Fu-jian, China. The results showed that microbial numbers of soil in mangrove and mudflat were significantly influenced by the salinity of dilution water and media. For bacteria, the seawater served as sterilized dilution water was significantly (P<0. 05) benefit to the counting on the plates than freshwater , but reverse results were found for actinomycetes and fungi. The increasing salinity of media in a range of 0-35%. significantly decreased microbial numbers on the plates, especially for actinomycetes, in spite of the fact that the effect of salinity of media on fungi numbers was not significant. The bacterial colonies were more abundant on the agar plates with low salinity than that in high salinity or without any NaCl. Based on these findings, when the dilution plate technique was applied in mangrove forest and mudflat at the same tidal level in intertidal zone, some methodological improvements should be put forward as following: the sterilized dilution water should be prepared with seawater for bacteria, but with freshwater or low saline water for actinomycetes and fungi; the salinity of plate media should be low when the microbes were isolated and their numbers were measured in mangrove areas.更多还原