Fungicidal control of groundnut leaf spot and rust in Nigeria

Four systemic fungicide formulations (tridemorph, tridemorph plus maneb, carbendazim and benomyl) and three non-systemic fungicides (captafol, mancozeb and copper oxychloride) were evaluated in field trials at two locations in Nigeria in 1981 and 1982 for control of early leaf spot (Mycosphaerella arachidis Deighton, stat: conid: Cercospora arachidicola Hori), late leaf spot (Mycosphaerella berkleyi W. A. Jenkins, stat: conid: Cercosporidium personatum (Berk. & Curt.) Deighton) and rust (Puccinia arachidis Speg.) of groundnut (Arachis hypogaea L.). Plots receiving mancozeb and tridemorph plus maneb showed best overall disease control and highest yields, followed by copper oxychloride. Benomyl and carbendazim controlled leaf spots predominantly while tridemorph controlled only rust. Captafol gave little overall disease control with yields only slightly better than untreated controls. Further tests are planned for tridemorph plus maneb and copper oxychloride using different concentrations and spray schedules.