The compatibility between biocontrol agents and pesticides seems to be a sustainable control strategy in agriculture. Therefore, the in vitro compatibility of three native isolates of Trichoderma was evaluated in three concentrations of chlorpyrifos (960, 1200, and 1440 mg/L), by determining the effect on spore germination, mycelial growth, and the antagonistic capacity. The isolates correspond to Trichoderma asperellum TCA 3, Trichoderma asperellum TCA 21 and Trichoderma harzianum TCA 23. Both spore germination and mycelial growth were performed using the poisoned medium method, while the antagonistic capacity was evaluated against Botrytis sp. in a dual culture. The results showed that TCA 21 strain had a higher germination percentage (79.46, 59.79, and 37.43%) than the TCA 3 and TCA 23 strains, in the three concentrations of chlorpyrifos. Regarding the mycelial growth of the three nat...