Spécies Diversity and Physiological Characterization of Fusarium spp. Isolates Causing Potato (Solanum tuberosum L.) Fusariosis (Far-North, Cameroon)

Abstract
Introduction: Potato production in the Far North Region, Cameroon is hampered by a wide range of fungi of the genus Fusarium. Aims: The aim of this work was to isolate and conduct physiological characterization of Fusarium spp. isolates responsible for potato Fusarium disease in the Far North Region, Cameroon. Methodology: Isolates were obtained from diseased organs (leaves) from fifteen villages in the district of Mogodé, Mokolo and Koza, Far North Cameroon. The species responsible for fusariosis were identified using several identification Keys on a base of symptoms and morphological spores characteristics (macroconidia, microconidia and chlamydospores). Fusarium incidence and rainfall were assessed. Radial growth, sporulation and pathogenicity of the isolates were use to evaluated the parameters of physiological characterization. Results: The overall average incidence of Fusarium head blight in the Far North Region, Cameroon is 29.36%. Furthermore, out of the 20 isolates obtained, six Fusarium species (Fusarium oxysporium, F. solani, F. equiseti, F. avenacearum, F. colmorum and F. sambicum) were identified. The highest growth rate (8.1 cm), the highest spore production (8 × 105) and the highest severity index (3%) were respectively obtained with the isolates FUROM 2 and FUTEK 3, FUMOG 1, FUMOG 2, FUROM 1 and FURAF from Mogodé District on PCA medium. Conclusion: Potato production in the Far North Region, Cameroon is confronted by various Fusarium species which have physiological characteristics that vary according to the area of origin of the isolates and the growing media.