Effects of Different Continuous Cropping and Rotation of Poplar Plantation on Soil Nitrogen Bacteria Community and Nitrogen Metabolism Characteristics of phosphate-solubilizing microbial community in the soil of poplar plantations under successive-planting and rotation. An Introduction to Metagenome Databases of Environmental Microbiology Cloning and idientifcation of β-glucosidase gene of uncultured microorganisms from biogas digester Gene Cloning of the Orange Carotenoid Protein from Cyanobacteria,and Its Ectopic Expression and Functional Evaluation in Escherichia coli Analysis,Comparison and Classification of Metagenomic Samples Application of metagenomic technique in the exploring of uncultured environmental microbial gene resource