Management of leaf spot diseases of peanut with fungicides and local detergents in Ghana

Abstract

Early leaf spot (Cercospora arachidicola) and late leaf spot (Cercosporidium personatum) of peanut (Arachis hypogaea) are a major constraint to peanut production in northern Ghana. To develop suitable disease management options, field trials were conducted from 2003 to 2005 at Nyankpala, Yendi and Damongo to compare the efficacy of the fungicides thiophanate methyl, benomyl and tebuconazole and the local detergents black soap and alata samina either alone or as a mixture. Final leaf spot ratings were recorded 72 days after sowing while biomass and pod yields were recorded at harvest. Leaf spot ratings, biomass and pod yields in local detergents and untreated control treatments did not differ across the three locations in 2003. However, fungicides suppressed disease and increased biomass and pod yields. In 2004 and 2005, leaf spot severity was reduced and biomass and pod yields increased compared to untreated control when local detergents were applied in combination or alternation with fungicides. Tebuconazole applied alone was the most effective fungicide in reducing leaf spot severity, resulting in significantly higher biomass and pod yields compared to most of the treatments. © 2007 Asian Network for Scientific Information.