México es el tercer productor de fresa a nivel mundial, donde la producción de este cultivo es de importancia económica y generación de divisas en el pais. El objetivo de la presente investigación fue identificar y caracterizar morfológicamente los hongos asociados a enfermedades en un cultivo de la fresa, así como determinar la capacidad antagónica <em>in vitro</em> de la cepa T-H4 de <em>Trichoderma harzianum</em> con los hongos identificados. Se colectaron muestras de plantas del cultivo de fresa con síntomas de enfermedades fúngicas, se sembraron en medio PDA y se generaron cultivos monospóricos para su caracterización morfológica. Los hongos identificados y la cepa T-H4 se confrontaron mediante cultivos duales. Se identificaron tres hongos asociados al fruto (<em>A. niger</em>, <em>Colletotrichum</em> sp. y <em>R. stolonifer</em>), tres en hojas y tallo (<em>Pestalotiopsis</em> sp., <em>Curvularia</em> sp. y <em>Alternaria</em> sp.) y dos hongos asociados a la raíz (<em>Rhizoctonia</em> sp. y <em>Fusarium</em> sp.). La cepa T-H4 presentó un nivel antagónico adecuado para <em>Colletotrichum</em> sp., <em>Pestalotiopsis</em> sp., <em>Alternaria</em> sp., <em>Rhizoctonia</em> sp. y <em>Curvularia</em> sp.,<em> in vitro.</em> Se sugiere realizar evaluaciones de control biológico con estos aislamientos en invernadero y a campo abierto, así como determinar su patogenicidad.

Entomopathogenic fungi are a large group of micro-organisms that provide multiple services to agroecological systems and have some advantages over chemical insecticides, since they produce mortality rates naturally and have less environmental impact. The production of biocontrol agents such as Beauveria bassiana finds multiple limitations, such as the adjustment of the optimum concentration of conidia and specific speed of death, among others. In addition, the potential that Mexican native strains can have for their use in the control of the grasshopper Sphenarium purpurascens (an edible insect but that behaves as a pest in several crops). In the present investigation, the mortality of two instars (or stages) of S. purpurascens in vitro plus the adult phase, was evaluated by applying bio-preparations of the MA-Bb1 strain in porous materials as support. The highest corrected mortality CM% and the highest specific speed of death K(d -1 ) of the orthopter for the different instants, as well as for the adult of S. purpurascens was presented in the bio-preparation (Zeolite + Diatomite + B. bassiana) at a concentration of 1 × 10 8 conidia mL -1 , presenting a viability of 89,1%. These results show the possibility for biocontrol with the use of the native Mexican strain MA-Bb1 of B. bassiana in combination with porous materials of diatomite and zeolite, in laboratory conditions.