What is Trichoderma harzianum?

Trichoderma harzianum is a species of fungus that is widely used as a biological control agent and seed treatment fungicide. Its role in agriculture primarily involves providing protection against various soil-borne pathogens that can affect plants at different growth stages. This beneficial fungus works by outcompeting harmful fungi for resources, producing enzymes that degrade fungal cell walls, and even inducing resistance mechanisms in plants.

By using Trichoderma harzianum in seed treatment, farmers can enhance seedling vigor and establish healthier crops that are more resistant to diseases. This application is particularly crucial in sustainable agriculture, where the reliance on chemical fungicides is reduced.

The other options, while pertaining to agriculture, do not correctly define Trichoderma harzianum in terms of its primary function and use. It is neither a fertilizer, a soil bacterium, nor a harmful pest, as these descriptions do not align with its characteristics or applications in the agricultural field.