title: [Effect of long-term application of nitrogen fertilizer on the diversity of nitrifying genes (amoA and hao) in paddy soil].
abstract: The aim of this study was to determine the effect of long-term (16 years) application of nitrogen fertilizer on the diversity of nitrifying genes (amoA and hao) in paddy soil on the basis of long-term paddy field experimental station (started in 1990) located in Taoyuan, with the molecular approaches of PCR, constructing libraries and sequencing. The fertilizer was urea and no fertilizer was as control. The Shannon index showed that long-term application of nitrogen fertilizer made the diversity of amoA gene descend while no effect on the diversity of hao gene. The LIBSHUFF statistical analyses demonstrated that both amoA and hao libraries of CK and N treatments were significantly different from each other and the rarefaction curves of libraries failed to meet the plateaus indicating that there were lots kinds of genes haven't been detected. The results of blasting with GenBank and the phylogenetic tree showed that the amoA genes detected in our study had a similarity with the uncultured gene of amoA, which showed some similar to Nitrosospira. Otherwise, the hao genes cloned showed a relationship to the genes of cultured bacteria such as Silicibacteria, Nitrosospira and Methylococcus, and the hao genes found in the N treatment dominated in alpha-Proteobacteria. These results suggest that long-term fertilization of nitrogen had significant impacts on the diversity or community of amoA and hao genes.
authors.affiliation: Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China. ccl-06.10@163.com
authors.forename: Chun-lan
authors.initials: CL
authors.lastname: Chen
authors.forename: Min-na
authors.initials: MN
authors.lastname: Wu
authors.forename: Wen-xue
authors.initials: WX
authors.lastname: Wei
mesh_terms: D001419:Bacteria / Q000235:genetics / Q000254:growth & development; D005308:Fertilizers; D005798:Genes, Bacterial; D014644:Genetic Variation; D020618:Methylococcus / Q000235:genetics / Q000254:growth & development; D058465:Nitrification; D009584:Nitrogen; D009606:Nitrosomonas / Q000235:genetics / Q000254:growth & development; D012275:Oryza / Q000254:growth & development*; D020560:Proteobacteria / Q000235:genetics / Q000254:growth & development; D012987:Soil / Q000032:analysis; D012988:Soil Microbiology; D013997:Time Factors
chemical_list: D005308:Fertilizers; D012987:Soil; D009584:Nitrogen