Trichoderma: Fungal Antagonist Used to Control Diseases in Agriculture

Abstract

Biocontrol or Biological Control can be defined as the use of natural organisms or genetically modified genes or gene products, to reduce the effects of undesirable organisms to favour organisms useful to human, such as crops, trees, animals and beneficial microorganisms. This strategy of control is ecologically clean and compatible with different models of agriculture: organic, biological and integrated pest/pathogen management (IPM) programmes. The main antagonist used in disease control in agriculture is the fungus Trichoderma, a low cost biocontrol agent that can establish it in different pathosystems, has moderate effects on soil balance and does not harm beneficial organism that contribute towards pathogen's control. This biocontrol agent has no harmful effects on humans, wildlife and other beneficial organisms. Trichoderma spp. is safe and effective biocontrol agents in both natural and controlled environments that does not accumulate in the food chain and to which resistance has not been described. Trichoderma strains used as biocontrol agents can act by colonising the soil and/or parts of the plant, occupying a physical space and avoiding the multiplication of the pathogens or producing cell wall degrading enzymes against the pathogens or producing antibiotics that can kill the pathogens or promoting the plant development and inducing the defensive mechanisms of the plant. Antifungal formulations based on Trichoderma strains and proteins require, as in the case of chemical fungicides, a costly and sound registration process previous to their commercialisation. For this reason, many of these biological products are being offered to the farmers under the category of fertilisers and other commercial products that are not tightly regulated, and, hence, they do not offer sufficient guarantee of quality and sanitary control. This fraud must be prosecuted since most of these wrongly registered formulations have not got a Trichoderma inoculums ’, shelf life or other properties stated on their label.