Pecan is susceptible to the occurrence of diseases capable of harming its development, and leaf spot caused by Cladosporium spp is among them. Therefore, the objective of this work was to analyze the potential antagonist and in vitro effect of volatile metabolites of Trichodermaspp. On Cladosporium spp. isolated from pecan leaf spots. Three Cladosporium spp. isolates and two commercial products based on Trichodermaspp. were used, as well as an isolate of the same genus provided by the 'ElocyMinussi' Laboratory of Phytopathology at UFSM. Cladosporium spp. mycelial growth was monitored in order to evaluate the morphological characteristics of the pathogen. The use of Trichoderma spp. as biocontrol was assessed through dual culture tests and production of volatile metabolites. Trichoderma spp. showed positive results in inhibiting the growth of Cladosporium spp., thereby presenting potential to be used as a biocontrol agent.
