title: Comparative effects of 3,4-dimethylpyrazole phosphate (DMPP) and dicyandiamide (DCD) on ammonia-oxidizing bacteria and archaea in a vegetable soil.
abstract: Nitrification inhibitors (NIs) 3,4-dimethylpyrazole phosphate (DMPP) and dicyandiamide (DCD) have been used extensively to improve nitrogen fertilizer utilization in farmland. However, their comparative effects on ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) in agricultural soils are still unclear. Here, we compared the impacts of these two inhibitors on soil nitrification, AOA and AOB abundance as well as their community structure in a vegetable soil by using real-time PCR and terminal restriction fragment length polymorphism (T-RFLP). Our results showed that urea application significantly increased the net nitrification rates, but were significantly inhibited by both NIs, and the inhibitory effect of DMPP was significantly greater than that of DCD. AOB growth was more greatly inhibited by DMPP than by DCD, and the net nitrification rate was significantly related to AOB abundance, but not to AOA abundance. Application of urea and NIs to soil did not change the diversity of the AOA community, with the T-RFs remaining in proportions that were similar to control soils, while the community structure of AOB exhibited obvious shifts within all different treatments compared to the control. Phylogenetic analysis showed that all AOA sequences fell within group 1.1a and group 1.1b, and the AOB community consisted of Nitrosospira cluster 3, cluster 0, and unidentified species. These results suggest that DMPP exhibited a stronger inhibitory effect on nitrification than DCD by inhibiting AOB rather than AOA.
authors.affiliation: MOE Key Laboratory of Environment Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China.
authors.forename: Qiuhui
authors.initials: Q
authors.lastname: Chen
authors.forename: Lingyu
authors.initials: L
authors.lastname: Qi
authors.forename: Qingfang
authors.initials: Q
authors.lastname: Bi
authors.forename: Peibin
authors.initials: P
authors.lastname: Dai
authors.forename: Dasheng
authors.initials: D
authors.lastname: Sun
authors.forename: Chengliang
authors.initials: C
authors.lastname: Sun
authors.forename: Wenjing
authors.initials: W
authors.lastname: Liu
authors.forename: Lingli
authors.initials: L
authors.lastname: Lu
authors.forename: Wuzhong
authors.initials: W
authors.lastname: Ni
authors.forename: Xianyong
authors.initials: X
authors.lastname: Lin
mesh_terms: D001105:Archaea / Q000187:drug effects* / Q000254:growth & development; D001419:Bacteria / Q000187:drug effects* / Q000254:growth & development; D058448:Biota / Q000187:drug effects*; D016000:Cluster Analysis; D019641:DNA, Archaeal / Q000737:chemistry / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D006146:Guanidines / Q000378:metabolism*; D008969:Molecular Sequence Data; D058465:Nitrification / Q000187:drug effects; D010802:Phylogeny; D012150:Polymorphism, Restriction Fragment Length; D011720:Pyrazoles / Q000378:metabolism*; D060888:Real-Time Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology; D014675:Vegetables / Q000254:growth & development
chemical_list: C433304:3,4-dimethylpyrazole phosphate; D019641:DNA, Archaeal; D004269:DNA, Bacterial; D006146:Guanidines; D011720:Pyrazoles; C004711:dicyandiamido