Allelopathy for weed control in acid soils with high organic matter

Resumo

Weeds are one of the major limiting factors in agriculture under temperate humid condi- tions. Weed control faces a challenge nowadays because developed societies reject synthe- tic herbicides based on risks for health and environmental conservation. Chemical weed control is dangerous for humans and the environment, and mechanical weeding is too expensive and labor consuming. Some of the new alternatives for weed control are based on allelopathy, which meets some of the new requirements in modern societies. Allelopathy opens interesting solutions that can be used for a sustainable agriculture and even for orga- nic agriculture. The allelopathy approach does not intend the elimination of weeds but the reasonable control of weed population at low levels that allow a sustainable agricultural production. Allelopathy can be made with alternative crops or with forest or agricultural residues. Some of the plants with allelopathy potential are leguminous such as faba been, but also forest residues as the green leaf of eucalyptus can be capitalized. These are partial solutions that can help in minimizing herbicide applications but further research is required.