Trichoderma atroviride (formerly T. harzianum) strain IMI 206040

This active substance consists of a specialized strain of the antagonist fungus that actively colonizes the rhizosphere and root surfaces of agricultural crops.

The mode of action is primarily mycoparasitism, where the fungus surrounds the pathogens' hyphae and secretes enzymes, such as chitinases and glucanases, that degrade their cell walls.

Beyond direct parasitism, strain IMI 206040 produces volatile organic compounds and secondary metabolites that inhibit the growth and germination of competing pathogenic spores.

The fungus also induces systemic acquired resistance (SAR) in plants, strengthening their natural defense mechanisms against a wider variety of biotic and abiotic stressors.

By competing for nutrients and space in the rhizosphere, it effectively displaces pathogenic populations, ensuring a healthier root system for the developing plant.

The agent is widely utilized as a biological fungicide to combat various soil-borne diseases that cause significant economic losses in horticulture and field crops.

Major targets for this biological control agent include, but are not limited to:

• Root rots caused by Pythium, Fusarium, and Rhizoctonia species.
• Damping-off diseases affecting seedlings and transplants.
• Vascular wilts in vegetable crops.
• Seed decay and post-harvest mold issues.

Application methods include seed coating, soil drenching at planting, or incorporation into potting substrates to protect the root zone from early infections.

The dosage and application timing must follow specific label recommendations, ensuring the density of the fungus is sufficient to establish a protective colony in the soil.

Soil moisture management is critical for success, as the fungus requires adequate hydration to grow and propagate within the soil structure.

Proactive application before disease symptoms appear is strongly recommended to establish the beneficial population before pathogens can gain a foothold.

In high-pressure situations or long growing seasons, repeat applications may be necessary to maintain effective colony counts within the treated soil area.

Strictly avoid the simultaneous application of chemical fungicides that target fungi, as these will directly kill the beneficial Trichoderma strain and negate its protective effect.

The efficacy of the strain is reduced in soils with extreme pH levels or poor organic matter content, which should be corrected to ensure favorable growth conditions.

The active agent is sensitive to prolonged direct sunlight; therefore, surface applications should be lightly incorporated into the topsoil to protect against UV degradation.

When preparing spray or drench solutions, avoid using water treated with chlorine or other broad-spectrum disinfectants, as they are toxic to the fungal spores.

Storage should be in a cool, dry, and dark environment to maintain high viability levels of the spores and prevent early germination or degradation during shelf life.