The Antifungal Activity Of Aqueous And Ethanol Extracts Of Jatropha Curcas L. Against Aspergillus Niger (Van Tieghem) That Cause Black Mould Rot Of Onion Bulbs In Sokoto, Nigeria

The antifungal activity of aqueous and ethanol extracts obtained from seed and leaf of Jatropha curcas were investigated using agar incorporation method in vitro against Aspergillus niger, a microbe known to be resistant to some chemical agents. Pathogenicity test revealed that A. niger was the pathogenic fungus that cause black mould rot of onion bulbs. The growth of A. niger was markedly suppressed by aqueous and ethanol extracts of leaf and seed, 65.7 and 57.0% at 160 mg/ml. The extracts at low concentration did not show considerable activity against the fungus except leaf ethanol extract 53.3% at 40 mg/ml.The in vivo study showed that aqueous extracts of seed and leaf reduced rot development, 59.4 and 54.4 % in onion bulbs. Highest rot inhibition 66.3 was obtained at 160 mg/ml seed extract.The result of the study suggest the potentials of J. curcas extracts as fungicidal agent that could be useful in management of black mould rot of onion bulbs caused by Aspergillus niger.