Plant diseases are considered as one of the serious limiting factors for the successful cultivation/ plantation of various agricultural, horticultural and forestry plants. As the yield losses are being estimated in alarming economic threshold levels every year, it is imperative to use appropriate control measures to manage the plant diseases. Although, chemical control is being used extensively by the farmers, it is exhibiting serious demerits and hence biological control is gaining momentum. Various bacterial and fungal species were already identified as promising biocontrol agents and are being used for the management of plant diseases. Among them, Trichoderma spp. are the most promising biocontrol agents and they are being mass multiplied, formulated and commercially available for farm applications. Therefore, research efforts were made to identify a promising Trichoderma, develop into biofungicide formulation and distribute the farmers for the management of root diseases in different crops. An effective strain of Trichoderma viride was isolated from soil, multiplied using molasses yeast medium and formulated with talc powder as biofungicide. This formulation was distributed to the farmers in Andhra Pradesh and Karnataka states for the management of root diseases in different crops. Impact assessment study carried out with the farmers have revealed that the application of T. viride effectively controlled the soil-borne root diseases in cotton, chilli, sugarcane and acid lime. Distribution of T. viride in large scale made tremendous impact on farmers in Andhra Pradesh, who are at present coming forward to buy the commercial products of biocontrol agents from the local market.