Phylogenic analysis of bacteria passed through 0 . 45 - μ m - pore - size fi lters in the rhizosphere

Molecular analyses of 16S rRNA gene cloning and sequencing methods were applied to identify microorganisms in environmental samples including, soil, seawater, and wastewater. The analyses revealed that the diversity of bacterial communities in the soil is highly complex and the soil contains bacteria which belong to the candidate phylogenic divisions (Rappė and Giovannoni, 2003). The candidate phylogenic divisions are known as the phylogenic divisions which did not contain cultivated relatives. The properties of the bacteria in the candidate phylogenic divisions have yet to be characterized because cultivation conditions for the bacteria have not yet been established. The rhizosphere is defi ned as the soil surrounding the roots that is infl uenced by living roots. This infl uence may occur by root exudation of carbon substrates that affect microbial communities. Therefore the rhizosphere is one good source for the analysis of the microbial communities of the soil because the soil of the rhizosphere contains relatively abundant bacteria. In the rhizosphere, it is well known that highly diverse of J. Gen. Appl. Microbiol., 56, 129‒136 (2010)