Trichoderma

Trichoderma is a genus of filamentous fungi in the family Hypocreaceae. Species are common in soil, decaying vegetation, wood, and the phyllosphere, where they often serve as rapid colonizers of organic material and roots. Many Trichoderma species are used for their biocontrol properties and plant growth–promoting effects.

Morphology and biology: Trichoderma species are fast-growing and typically produce branched vegetative mycelia and distinctive conidiophores bearing green to olive conidia. They reproduce primarily asexually, though some species have a sexual stage in the genus Hypocrea. They are saprotrophs and frequent mycoparasites, able to attack other fungi by coiling around hosts and secreting enzymes such as chitinases, glucanases, and proteases.

Ecology and role: In natural ecosystems, Trichoderma contributes to nutrient cycling and can form associations with plant roots as endophytes or colonizers, sometimes enhancing plant growth and stress tolerance. Through antagonism and competition, they help suppress soil-borne plant pathogens, contributing to disease suppression in agroecosystems.

Applications: Trichoderma species are widely employed as biological control agents in agriculture and horticulture. Commercial products include strains such as Trichoderma harzianum, T. viride, T. atroviride, and T. asperellum. They control pathogens such as Botrytis, Fusarium, and Pythium via mycoparasitism, antibiosis, and induced plant defenses, and are used as seed coatings, soil drenches, or foliar applications.

Safety and regulation: Generally regarded as safe for humans and most environmental contexts, although rare opportunistic infections have been reported in severely immunocompromised individuals. The ecological impact is typically positive, but monitoring non-target effects on microbial communities is advised in some settings.