The research with the aim of isolating biotypes of Trichoderma sp from different places and assess the impact of biological control using Trichoderma sp Stemphyllium solani causing "tomato blight or gray leaf spot" in San Martin. The experiment in running Plant Health Laboratory-Pathology, located in University City in the district of Morales and the Fundo Aucaloma located to 15 km from the district of Morales, South Latitude 6 º 20 'West Longitude 76 º 21' 720 m.s.n.m.m altitude area of tropical moist forest life (bh-PT) within the jurisdiction of the district San Antonio Rio Cumbaza, province and region of San Martin. Both are from the National University of San Martin - Tarapoto; under completely randomized block design with tour replications and eight treatments. Were isolated and multiplied, six strains of Trichoderma sp. They were coded as CFC (founded Cepa cacatache) CJG (Cepa J...