Biochemical pathways used by microorganisms to produce nitrous oxide emissions from soils fumigated with dimethyl disulfide or allyl isothiocyanate

Publication date: Available online 25 January 2019Source: Soil Biology and BiochemistryAuthor(s): Wensheng Fang, Dongdong Yan, Bin Huang, Zongjie Ren, Xianli Wang, Xiaoman Liu, Yuan Li, Canbin Ouyang, Quirico Migheli, Aocheng Cao, Qiuxia WangAbstractDespite using fumigants for many decades to control soil-borne pathogens and plant-parasitic nematodes, the influence of soil fumigation on microorganisms involved in the nitrogen-transforming process remains little understood. We used real-time PCR (quantitative polymerase chain reaction) and 16S rRNA gene amplicon sequencing techniques to determine nitrous oxide (N2O) emissions from bacterial microorganisms associated with nitrogen (N) transfer when soils were fumigated with dimethyl disulfide (DMDS) or allyl isothiocyanate (AITC). Our results showed that fumigation with DMDS or AITC increased N2O emissions 6.5–7.3 and 11.2–20.7 times, respectively. The abundance of 16S rRNA and N cycling functional genes initially decreased, but recovered to the unfumigated levels after fumigation. N2O emissions were significantly correlated to the presence of NH4+, NO3−, dissolved amino acids (DAA) and microbial biomass nitrogen (MBN). N2O emissions were not correlated with the abundance of N-transforming functional genes. Metatranscriptomes and dual-label 15N18O isotope anaylsis revealed DMDS fumigation significantly increased the expression of gene families involved in the N-transforming process, but depressed ammonia oxidation which c...
Source: Soil Biology and Biochemistry - Category: Biology Source Type: research