For the antibiosis test, liquid cultures of the selected Trichoderma isolates were grown for 14 days in MIN media at 25 °C with shaking at 150 rpm. Mycelia were then removed using four layers of sterile cheese cloth. The liquid cultures were filtered using a 0.22 μm syringe filter system (Millipore, Billerica, MA, USA). Agar plates were prepared by adding 4.5 mL of liquid culture filtrate and 4.5 mL of MIN 3% Bacto agar to small plates (6 cm diameter). Control plates contained uninoculated MIN broth instead of Trichoderma liquid culture filtrate ( Bae et al., 2011). Phytophthora plugs (0.6 cm diameter) were then placed mycelial side down in the middle of each plate and incubated at 18–30 °C for 5–13 days. The colony diameters of each Phytophthora isolate were measured daily. Growth inhibition (%) by the extract relative to the control was calculated as a percentage using the formula given above. Experiment was repeated twice, with three biological replications per experiment.