In vitro antagonistic activity evaluation of some selected fungi isolated from burned soils in Mila region (East of Algeria)

The present study was initiated to (i) determine burned forest-inhabiting fungi in Zouagha, TerriBeinène, Mila and (ii) study the antagonistic activities of Trichoderma sp against Fusarium sp, Penicillium sp, Rhizoctonia sp, and Alternaria sp. Eighteen fungal strains representing six genera were isolated from soil samples obtained from the burned forest of Zouagha in the Mila region: Trichoderma sp, Fusarium sp, Penicillium sp, Rhizoctonia sp, Alternaria sp, and Rhizopus sp. The direct antagonistic activity assays of Trichoderma sp on Potato Dextrose Agar medium (PDA) against the four fungi: Fusarium sp, Penicillium sp, Rhizoctonia sp, and Alternaria sp revealed that the fungus Trichoderma sp reduced the mycelium growth of Fusarium sp, Penicillium sp, Rhizoctonia sp and Alternaria sp to 23.13, 33.13, 33.75, and 38.31%, respectively, compared to the control after six days at room temperature. The results illustrated an inhibitory action of the antagonist Trichoderma sp characterized by slowing the mycelial growth of fungal strains. Strains of Fusarium sp, Penicillium sp, Rhizoctonia sp and Alternaria sp showed differences in the sensitivity to the antagonist. Because Trichoderma occurred more frequently in burned soils and were more antagonistic to phytopathogenic fungi in culture than isolates from unburned soils, the judicious use of fire may increase the abundance of Trichoderma isolates and their inhibitory action may be used for the control of fungal plant diseases.