The influence of organic fertilizers on soil microbiota within 2 years

We hypothesized that organic fertilizers increase the abundance of pathogenic microorganisms in amended soil; however, their occurrence might be just temporary, and their levels decreased within the time from the last fertilization. To prove this hypothesis, we used field trials established in 1996, where the sewage sludge and manure amendments were regularly applied every third year. We monitored the levels of potentially pathogenic microorganisms at different times since the fertilizer application in September 2015.