Overview of Mechanisms and Uses of Trichoderma spp.

Phytopathology (Impact Factor: 3.12). 03/2006; 96(2):190-4. DOI: 10.1094/PHYTO-96-0190
Source: PubMed


ABSTRACT Fungi in the genus Trichoderma have been known since at least the 1920s for their ability to act as biocontrol agents against plant pathogens. Until recently, the principal mechanisms for control have been assumed to be those primarily acting upon the pathogens and included mycoparasitism, antibiosis, and competition for resources and space. Recent advances demonstrate that the effects of Trichoderma on plants, including induced systemic or localized resistance, are also very important. These fungi colonize the root epidermis and outer cortical layers and release bioactive molecules that cause walling off of the Trichoderma thallus. At the same time, the transcriptome and the proteome of plants are substantially altered. As a consequence, in addition to induction of pathways for resistance in plants, increased plant growth and nutrient uptake occur. However, at least in maize, the increased growth response is genotype specific, and some maize inbreds respond negatively to some strains. Trichoderma spp. are beginning to be used in reasonably large quantities in plant agriculture, both for disease control and yield increases. The studies of mycoparasitism also have demonstrated that these fungi produce a rich mixture of antifungal enzymes, including chitinases and beta-1,3 glucanases. These enzymes are synergistic with each other, with other antifungal enzymes, and with other materials. The genes encoding the enzymes appear useful for producing transgenic plants resistant to diseases and the enzymes themselves are beneficial for biological control and other processes.

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Available from: Gary Harman, Oct 16, 2014
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    • "Neher et al., 2013). Soil bacteria and fungi promote soil fertility, stimulate plant growth and plant defence mechanisms against patogens (Harman, 2006; Contreras-Cornejo et al., 2009). "
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    Bioresource Technology 09/2015; 198(December 2015):520–532. DOI:10.1016/j.biortech.2015.09.034 · 4.49 Impact Factor
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    Microbiology 09/2015; DOI:10.1099/mic.0.000167 · 2.56 Impact Factor
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    • "In addition, several Trichoderma strains have been shown to have direct effects on plants, increasing their growth potential and nutrient uptake, fertilizer use efficiency, percentage and rate of seed germination, and stimulation of plant defenses against abiotic damage (Shoresh et al., 2010). Recently, the production of Trichoderma related substances of plant growth as indole-3-acetic acid (IAA), which is considered the most important plant growth promoter was reported (Harman, 2006; Samuels et al., 2006). Some pathways routes for IAA synthesis are also reported in plants and microorganisms. "

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