With the objective of identifying the causal agent of the main fungous illnesses in Tomato (Lycopersicon esculentum) in San Martín county and to evaluate the effect of the food poisoned with different fungicides in the development of the pathogens, it was carried out the present investigation work, in the laboratory of Vegetable Sanity of the National University of San Martin; likewise for the test of the poison food it put on in mixture the following fungicides: Mancozeb, Benomil, Kresoxin metil, Tebuconazole, Tiofanate metil, Tiofanate metil + thiram, Triflumizole, Compropanil, Tolylfluanid, Plocloraz, Mancozeb + Benomil, Mancozeb + Metalaxil (48 - 10%) and Mancozeb + Metalaxil (64 - 8%). The mushrooms identified in the tomate cultivation were Fusarium oxysporum, Sclerotíum rolfsii, Altemate altemata, Cercospora solaní, Stemphylíum sotaní, Botrytis cínerea, Curvularia sp., Collet...