Microbial Diversity in Soil: Effects on Crop Health

From the plant pathologist's point of view, the soil not only provides nutrients and water for plant growth, but is also considered a hostile environment harbouring plant pathogenic fungi, bacteria and nematodes. Until recently, the most common attitude was to try to eliminate the plant pathogenic microorganisms by biocidal or other treatments. These treatments are frequently hazardous for humans and the environment, but are also inefficient, since they have to be applied every year to control soilborne pathogens and parasites. The most effective treatments kill off a large part of the microbial communities, which are essential for limiting the expression of the parasitic activities of the pathogens.