Here we describe the detection of in vitro anti-phytopathogenic fungal activity using the broth dilution method to find the MIC (minimum inhibitory concentration) of an aqueous extract of leaves. Four concentrations were assayed: 1, 2.5, 5, and 10% (v\/v) in PDB medium. Each concentration was inoculated with a spore suspension of the selected fungus. PDB without spores was used as negative control and with the addition of a commercial fungicide like positive control. After the inoculation of the fungus, the tubes were incubated for three days in the dark at 26-28 \u00b0C. After the incubation time, the tubes were checked for growth of the fungus, if no growth is observed, 25 \u03bcL of the suspension are transferred to PDA medium in Petri dishes of 3 cm diameter. Evaluations were made on day 7. The MIC was determined as the lowest concentration of aqueous extract preventing the growth of macroscopically visible mycelium.