Isolation And Identification Of Actinomycetes From The Soil Of Root System Of Mangrove Forest In Zhanjiang

From 2008 to 2011, we collected samples from zhanjiang mangrove national reserve area, identify actinomycetes by polyphasic taxonomy, in order to the systematic investigation of species and the amount of mangrove actinomycetes.Five hundred and fifty soil samples have been collected from Gaoqiao and Techeng Island Mangrove National Nature Reserve area, according to the types of trees(Avicennia maria,Aegiceras corniculatum,Bruguiera gymnorrhiza) in protected areas of mangrove and the tidal zone(high,middle,low tidal zone). Respectively, 110 isolates , 85 isolates were selected from the soil samples which were collected from Gaoqiao and Techeng Island. In a word , a total of 195 strains were collected. The number of actinomycetes in per gram soil samples from Gaoqiao(3.5×10~3-5.5×10~3 cfu/g) was more than it from Techeng Island(1.5×10~2-1.33×10~3 cfu/g). The most abundance of actinomycetes(5.5×10~3 cfu/g) was the rhizosphere soil of Aegiceras corniculatum in the Gaoqiao region. And in the Techeng Island, more actinomycetes were in the middle soil layers(5-10cm) than suface (0-5cm)and deep soils(10-15cm), from the same palce.195 isolates were primarily classified by their morphology on the agar plates, selecting 36 strains for the next study. We identified 36 strains with polyphasic taxonomy. Based on morphological characteristics, thirty-six strains were divided into six groups. There were Albosporus group, Aureus group, Cinerogriseus group, Globisporus group, Griseorubroviolaceus group, Roseosporus group. The Albosporus and the Cinerogriseus were dominant group. The results of chemotaxonomy showed:thirty-six were divided into two groups: the cell-wall type areⅠ/C type andⅢ/C type, according to the difference of amino acid and the sort of monosaccharide. Based on the nearly all sequence of 16SrDNA of the thirty-six strains,they were also divided into two groups: Streptomyces and Nocardiopsis. According to the results of polyphasic taxonomy,the phylogenetic relationship of thirty-six strains were defied that thirty-five strains belonged to Streptomyces(97.2%), strain 40 belonged to Nocardiopsis(2.8%), the Streptomyces was regnant actinomycetes.