RAPD-PCR Profiling of Trichoderma Species from Agricultural Soils in Benue State and Their Biocontrol Potential

Trichoderma species are ubiquitous soil fungi with well-documented biocontrol potential against phytopathogenic fungi, making them valuable candidates for sustainable agriculture in Nigeria. Molecular characterization of indigenous Trichoderma isolates is essential to identify region-specific strains with optimal biocontrol activity. This study profiled Trichoderma species from agricultural soils in Makurdi and Gboko, Benue State, North Central Nigeria, using random amplified polymorphic DNA (RAPD) PCR. Soil samples were collected from yam, sorghum, and maize farms. Trichoderma isolates were obtained by dilution plating on potato dextrose agar and identified by colony and microscopic morphology. RAPD fingerprinting was performed with five arbitrary 10-mer primers, and in vitro antagonism against Fusarium oxysporum and Sclerotium rolfsii was assessed by dual culture assay. Forty-two Trichoderma isolates were obtained. RAPD profiling resolved 6 genetic clusters that partially correlated with morphological species groupings. Isolates classified as T. asperellum and T. harzianum demonstrated the highest inhibition zones against both test pathogens (65-78%). These findings identify promising indigenous biocontrol strains from Benue State soils and support their evaluation in field-based trials on food crops. Keywords: Trichoderma, RAPD-PCR, biocontrol, phytopathogen, Benue State.