Summary.
Farmers increasingly leave crop residues on the soil surface rather than incorporating them into the soil, increasing soil moisture and crop yields.
However, many soil-borne pathogens survive in the previous year's crop residues, making disease more problematic under reduced tillage.
Reduced tillage can favor pathogens by mechanisms such as protecting the pathogen's refuge in the residue from microbial degradation, lowering soil temperature, increasing soil moisture, and leaving soil undisturbed.
In order for reduced tillage to become more popular, additional controls are needed for pathogens. The four control tactics, chemical, biological control, host resistance and cultural control, can be used to limit damage from diseases.
It is highly recommended, however, that crop rotation be coupled with reduced tillage. This practice controls many diseases and yet allows as much of the crop residue as possible to be retained on the soil surface.
