Isolation, Identification and Phylogenetic Relationship of Environmental Strains of Aeromonas spp. from Zhongshan Area, Guangdong Province

Ten strains of Aeromonas spp. using a selective media Aeromonas agar base were isolated from the water, sediment and intestine content of healthy fish in fish ponds as well as the mud sample taken from rice fields, in Zhongshan city, Guangdong Province. They were identified by means of conventional physiological and biochemical tests together with 16S rDNA sequencing. In addition, the phylogenetic relationship between these strains and some type strains of Aeromonas spp. was analyzed based on their 16S rDNA sequences. Aeromonas hydrophila was found to be the most frequently isolated Aeromonas species as expected. Other isolates were identified as Aeromonas caviae, A. jandaei, A. veronii, respectively, among which A. jandaei and A. veronii were new record of Aeromonas species in China. This is the first study for the diversity of Aeromonas species in the environment in our country.