EN
Microbial and biochemical analyses of soil under winter wheat in a field trial with various cultivation systems (organic, conventional and monoculture) were performed during 3 growing seasons: 2001, 2002 and 2003. The activities of the tested enzymes (dehydrogenase and phosphatases) and microbial biomass C and N contents in the monoculture soil were generally significantly lower than those in the soil from the organic and conventional–short rotation systems, indicating that substantial disturbances may occur in the microbial activity of the monoculture soil.