Within the last 6 months I worked on questions dealing with denitrification reactions carried out by fungi. Experiments on fungal pure cultures were done under controlled atmospheric conditions to determine the capability of NO and N2O production from these organisms under anoxic conditions. Although fungal denitrification is considered to account for significant amounts of N2O emissions in certain soil environments, we still lack information about the molecular tools of these organisms, with the exception of a few well-studied strains, even though more and more fungi are reported to be able to produce N2O gas from nitrate or nitrite in literature.
In our data, only the strains belonging to the Fusarium family showed a significant production of N2O in the culture vials from nitrite. All other tested cultures showed no or very little N2O production, which stands in contrast to previous published data for some strains.
These findings can be used to re-interpret the role of fungi in denitrification processes in soil environments, suggesting that their direct participation in these processes might be overrated. The results also serve as a base for a molecular analysis of the tested strains where the presence or absence of key enzymes will be targeted.