Search results for "NOSZ GENE"

Long-term effects of contrasting tillage on soil organic carbon, nitrous oxide and ammonia emissions in a Mediterranean Vertisol under different crop…

2018

This 2-year study aimed to verify whether the continuous application of no tillage (NT) for over 20 years, in comparison with conventional tillage (CT), affects nitrous oxide (NO) and ammonia (NH) emissions from a Vertisol and, if so, whether such an effect varies with crop sequence (continuous wheat, WW and wheat after faba bean, FW). To shed light on the mechanisms involved in determining N-gas emissions, soil bulk density, water filled pore space (WFPS), some carbon (C) and nitrogen (N) pools, denitrifying enzyme activity (DEA), and nitrous oxide reductase gene abundance (nosZ gene) were also assessed at 0–15 and 15–30 cm soil depth. Tillage system had no significant effect on total NH e…

Abundance of narG, napA, nirK and nosZ genes of denitrifying bacteria in a Norway spruce forest under different N-deposition

2007

Genetic and Environmental Controls on Nitrous Oxide Accumulation in Lakes

2015

We studied potential links between environmental factors, nitrous oxide (N2O) accumulation, and genetic indicators of nitrite and N2O reducing bacteria in 12 boreal lakes. Denitrifying bacteria were investigated by quantifying genes encoding nitrite and N2O reductases (nirS/nirK and nosZ, respectively, including the two phylogenetically distinct clades nosZ(I) and nosZ(II)) in lake sediments. Summertime N2O accumulation and hypolimnetic nitrate concentrations were positively correlated both at the inter-lake scale and within a depth transect of an individual lake (Lake Vanajavesi). The variability in the individual nirS, nirK, nosZ(I), and nosZ(II) gene abundances was high (up to tenfold) a…

Technical committee of the project SYMGES

2013

EA Pôle MERS. Rapport final de contrat de recherche INRA (communication orale invitée, 46 slides). Présenté le 24 septembre 2013 au BASF SE, Limburgerhof en Allemagne par Cécile Revellin seule. SYMGES – Projet partenarial (2013) – Coordination C. Hénault, UR SOLS Conduit avec l’unité d’Agroécologie de Dijon, en partenariat avec un industriel des biotechnologies agricoles, ce projet étudie la capacité des rhizobia (microorganismes vivant en symbiose avec les légumineuses et possédant la capacité de fixer l’azote) à réduire le N2O en N2 pour utiliser cette fonction microbienne afin de réduire les émissions du gaz à effet de serre par les sols agricoles.

Direct seeding mulch-based cropping increases both the activity and the abundance of denitrifier communities in a tropical soil

2009

International audience; This study evaluated the impact of direct seeding mulch-based cropping (DMC), as an alternative to conventional tilling (CT), on a functional community involved in N cycling and emission of greenhouse gas nitrous oxide (N2O). The study was carried out for annual soybean/rice crop rotation in the Highlands of Madagascar. The differences between the two soil management strategies (direct seeding with mulched crop residues versus tillage without incorporation of crop residues) were studied along a fertilization gradient (no fertilizer, organic fertilizer, organic plus mineral fertilizers). The activity and size of the denitrifier community were determined by denitrifica…

Disentangling the rhizosphere effect on nitrate reducers and denitrifiers: insight into the role of root exudates.

2008

International audience; To determine to which extent root-derived carbon contributes to the effects of plants on nitrate reducers and denitrifiers, four solutions containing different proportions of sugar, organic acids and amino acids mimicking maize root exudates were added daily to soil microcosms at a concentration of 150 μg C g−1 of soil. Water-amended soils were used as controls. After 1 month, the size and structure of the nitrate reducer and denitrifier communities were analysed using the narG and napA, and the nirK, nirS and nosZ genes as molecular markers respectively. Addition of artificial root exudates (ARE) did not strongly affect the structure or the density of nitrate reduce…

Characterization of denitrification gene clusters of soil bacteria via a metagenomic approach

2009

International audience; Denitrification is a microbial respiratory process contributing to the emission of greenhouse gas. The study of denitrifying bacteria, like that of others, is hindered by characteristics that can prevent up to 99% of soil bacteria from being cultivated in vitro. New approaches based on the direct extraction of DNA from the natural environment and PCR amplifications can overcome limitations due to bacterial unculturability, but until now their application to denitrification genes has led only to the recovery of partial sequences for some of these genes.Our goals in this study were to apply a metagenomic approach characterized by cloning of DNA extracted from soil and …

Denitrifying microbial communities along a boreal stream with varying land-use

2019

Streams have an important role in regulating nitrogen (N) transportation from terrestrial ecosystems to downstream waters. Here, we examined how catchment land-use affects potential denitrification rates and the function and composition of denitrifier communities in boreal stream sediments, using stable isotope incubations and qPCR and 454-pyrosequencing targeted on nirS, nirK and nosZ genes. Although land-use influenced the water chemistry as higher nitrite + nitrate (NO x − ) concentration at the agriculture-affected sampling point, sediment organic matter content was found to be the key factor in regulating potential denitrification rates. However, the abundance as well as the diversity …