Identification of Seed-Borne Fungi on Sesame (Sesamum indicum) in Niger State, North Central Nigeria

Sesame (Sesamum indicum) has become an increasingly important cash crop in Niger State, driven by export demand and increasing domestic processing of sesame oil and paste. The health of planting seed is foundational to the establishment of pathogen-free sesame stands, yet little documented information exists on the fungi harboured in sesame seeds traded and planted within the state. This study assessed the diversity and prevalence of seed-borne fungi associated with sesame seeds from five major producing and trading communities in Niger State. Seeds were collected from farmer stores, agro-dealer shops, and local markets and subjected to blotter test, agar plate, and deep-freeze blotter seed health testing methods. Laboratory results identified Aspergillus flavus, Fusarium oxysporum, Alternaria sesami, Cercospora sesami, and Macrophomina phaseolina as the primary seed-borne fungi, with A. flavus detected in 68 percent of tested seed lots. Seed germination rates were inversely correlated with levels of seed-borne fungal contamination. Market-traded seeds showed significantly higher pathogen loads than seeds from organised cooperative storage systems. The study recommends mandatory seed health certification for sesame planted in commercial production systems and the promotion of farmer-managed seed cleaning and solar drying protocols to reduce seed-borne fungal loads. Keywords: sesame, seed-borne fungi, Aspergillus flavus, Niger State, seed health.