Correct Answer - D
Trichodema is a genus of fungi that is present in all soils. Several strains of Trichoderma have been developed as biocontrol agents against fungal diseases of plants. The various mechanisms include antibiosis, parasitism , inducting host-plant resistance and competition. Most biocontrol agents are from the species T. harzianum , T. viride and T. haratum. The biocontrol agent generally grows in its natural habibat on the root surface and so. affects root diseases in particular but can also be effective against foliar diseases.
