Antagonistic Capacity of Trichoderma harzianum Rifai against Fungal Pathogen Sclerotium oryzae (Catt.)

Context: The antagonistic capacity of Trichoderma harzianum Rifai against fungal pathogen Sclerotium oryzae (Catt.) strain A-34, and the action mechanisms against the fungal pathogen of Sclerotium oryzae (Catt.), which caused crop losses. Aim: To evaluate the antagonistic capacity of Trichoderma harzianum Rifai against the fungal pathogen Sclerotium oryzae (Catt.). Methods: The concentration of spores/ml-1, the viability and mycelia growth inhibition of the pathogen, and the antagonistic capacity of Trichoderma harzianum, through the action mechanisms. The results were processed using SPSS, version 22.0, for Windows, and Tukey’s test results had a 0.05% probability. A completely randomized experimental design was used for each pathogenic fungus. Results: No antibiosis was observed at 24 hours because the antagonistic did not inhibit pathogen growth; at 72 hours, there was hyphal interaction between S. oryzae and T. harzianum, and there was no mycoparasitism by the antagonist. S. oryzae grew more than the antagonistic at 96 hours, and at 120 hours, the antagonistic grew more than S. oryzae; therefore, no antagonistic or hyper-parasitic activity were observed in the pathogen. Conclusions: The antagonist did not affect the mycelial growth of S. oryzae during the dual challenge. Likewise, T. harzianum (strain A-34) showed no antagonistic activity against Sclerotium oryzae, with a negative inhibition percent of Radial Growth, seen through antibiosis and the action mechanisms.