Antifungal Effect of Argel (Solenostemmaargel Del. Hayne) alcoholic Extract and Fungicide (Amstar top) on fungus (Fusariumoxysporump.flycopersici) Causal Agent of Wilt in Mango

Abstract

Fusarium wilt is considered as one of the most important diseases of this crop worldwide. The present investigation was undertaken under laboratory conditions of Plant Protection Department, College of Agricultural Studies, Sudan University of Science and Technology to study the effect of different Argel alcoholic extract concentrations as higher plant extracts and synthetic fungicides, Amistar top 200/ml, on the growth of the fungus Fusariumoxysporum f.sp. mangiferae causal agent of wilt disease in mango, under laboratory conditions in order to formulate promising disease management approach. The fungus used in this was first confirmed as Fusariumoxysporumf. sp. mangiferaeassociated with Fusarium wilt in mango based on its morphological and cultural characters. Three concentrations of the Argel extract (25, 50 and 100 %) and fungicide at standard rate were used in addition to control. The assessment of their inhibitory effect against the pathogen was expressed as fungal growth inhibition percentage. The results obtained showed that Argel extract at all concentrations (25, 50 and 100 %) as well as the fungicide reduced significantly (P<0.05) the fungal growth 1.32, 1.25, 1.2, 1.92 respectively compared to untreated control. Moreover, the fungicide at 100% concentration (0.2\100ml) demonstrated the highest inhibition of fungal growth (1.0) followed in descending order by Argel concentrations. Among Argel concentrations, the highest one (100) reduced significantly the growth of the fungus (1.2). Generally, the results showed that the antifungal activity increase with increase in extract concentration. Obviously, the test fungus differs in its response to the different concentrations but on the whole, growth inhibition increased with the concentration.