<i>In vitro</i> antagonistic activity of <i>Trichoderma</i> spp. against fungal pathogens causing black point disease of wheat
Mohamed Taha Yassin, Ashraf Abdеl-Fattah Mostafa, Abdulaziz A. Al–Askar
Abstract
Black point disease of wheat contributes to high economic losses every year. The overuse of fungicides resulted in pathogenic fungal resistance, health and environmental hazards that necessitate the formulation of safe biocontrol agents. Dual cultural assay of Trichoderma viride and Trichoderma harzianum strains proved their highest efficiency against Alternaria alternata with inhibition percentages of 75.04 and 67.83%, while the lowest activity was detected against Drechslera halodes with growth inhibition of 51.54 and 43.92%, respectively. Alternaria alternata and D. halodes strains exhibited carbendazim resistance, while Fusarium proliferatum was the most susceptible one. Chemical analysis of T. harzianum and T. viride extracts using gas chromatography-mass spectrometry indicated that 6-pentyl-α-pyrone and cyclooctanol compounds were the main active constituents representing about 26.43 and 32.74% respectively. The tested bioagents were highly effective against the fungal strains causing black point disease of wheat so that these biocontrol agents could be used in formulation of natural fungicides avoiding the harmful impact of the synthetic fungicides.Abbreviations: FCZ; Fluconazole Antifungal agent, GC-MS; Gas chromatography-Mass spectrometry, MIC; Minimum inhibitory concentration, MFC; Minimum fungicidal concentration, PDA; Potato dextrose agar, T.H; Trichoderma harzianum, 1. T. V; Trichoderma viride