EN
Fusarium basal rot disease of onion caused by Fusarium oxysporum f. sp. cepae is an economically vital disease-causing threat to onion cultivation and storage. This study evaluated the effect of three plant extracts, Eucalyptus (Eucalyptus camaldulensis), Ginger (Zingiber officinale), and Moringa (Moringa oleifera), on the management of the Fusarium basal rot pathogen (Fusarium oxysporum f. sp. cepae). The study was conducted at the pathology laboratory of the Department of Crop Protection, Bayero University, Kano. The treatments comprised of three plant extracts (Ginger, Moringa, and Eucalyptus) and five levels of concentration (0, 25%, 50%, 75%, and 100%) and synthetic chemical fungicide (Ridomil Gold), which were factorially combined and replicated three times in a completely randomized design (CRD), were used to evaluate for their inhibitory effects on F. oxysporum growth in vitro. The result from the mycelial growth revealed that Moringa and Ginger at 100% concentration significantly (P < 0.05) recorded the lowest mycelial growth rates compared to control. Furthermore, Ginger and Moringa recorded a higher percent of growth inhibition. Lower concentrations of 25 and 50% exhibited the least percent growth inhibition compared to control. It was concluded that the plant extracts used at different concentrations showed promising prospects for control of F. oxysporum growth in vitro. Moringa and ginger extracts at 75% and 100% concentration significantly (P < 0.05) inhibited the growth of the fungus and could therefore be recommended for further studies in the screen house and field to evaluate their efficacies against Fusarium basal rot under field conditions in combating the post-harvest losses of onions.