Trichoderma harzianum is a beneficial soil fungus widely used in agriculture for its ability to promote plant growth, protect against pathogens, and enhance soil health. Below is a concise overview of how plants can benefit from Trichoderma harzianum:
Biocontrol of Pathogens:
Trichoderma harzianum is a potent biocontrol agent that suppresses soil-borne pathogens such as Fusarium, Rhizoctonia, Sclerotinia, and Pythium through mycoparasitism, where it directly attacks and degrades fungal pathogens.
It produces antifungal metabolites (e.g., gliotoxin, peptaibols) and enzymes (e.g., chitinases, glucanases) that inhibit pathogen growth, reducing diseases like root rot, damping-off, and wilt.
It induces systemic resistance (ISR) in plants, boosting their natural defenses against a broad range of fungal and bacterial diseases.
Plant Growth Promotion:
Trichoderma harzianum enhances root development by producing growth-promoting compounds, such as auxins and secondary metabolites, leading to improved nutrient and water uptake.
It solubilizes nutrients like phosphorus, iron, and zinc, making them more available to plants, which supports vigorous growth and higher yields.
Stress Tolerance:
The fungus helps plants withstand abiotic stresses like drought, salinity, and heavy metal toxicity by enhancing root system resilience and producing stress-mitigating enzymes.
It forms symbiotic relationships with plant roots, improving soil-root interactions and water retention under adverse conditions.
Soil Health Improvement:
Trichoderma harzianum enhances soil microbial activity and organic matter decomposition, improving soil structure and fertility.
It contributes to bioremediation by degrading pollutants like pesticides and heavy metals, creating a healthier soil environment for plant growth.
Seed Germination and Vigor:
When applied as a seed treatment, Trichoderma harzianum improves germination rates and seedling vigor by protecting seeds from pathogens and enhancing early growth.
Applications:
Used as a biofungicide, biofertilizer, or soil amendment in sustainable agriculture to reduce chemical inputs.
Applied via seed coating, soil drenching, root dipping, or foliar spraying for optimal results.
Examples:
Studies show Trichoderma harzianum increasing yields in crops  by controlling diseases and promoting growth.
It’s particularly effective in greenhouse and organic farming systems for managing soil-borne diseases and improving crop resilience.