Ajayi, Folorunso A.Lale, N.E.S.Joshua, S.D.2023-12-112023-12-111999-03-01F.A. AJAYI1, N.E.S. LALE1*, and S.D. JOSHUA2 . !Department of Crop Science, Faculty of Agriculture, University of Maiduguri, P.M.B. 1069, Maiduguri, Nigeria. 2University of Maiduguri Farm, P.M.B. 1069, Maiduguri, Nigeria.https://keffi.nsuk.edu.ng/handle/20.500.14448/3013Field trial was conducted from October 1998 to March 1999 in Maiduguri, Nigeria to evaluate the effectiveness o f neem seed oil (NSO) applied in water emulsified with soap in controlling tomato fruitworm, Helicoverpa (Heliothis) armigera in irrigated tomato. NSO significantly reduced the populations o f H. armigera larvae and the number and weight of damaged tomato fruits. NSO applied at the rate o f 20 ml/4 m2 provided better protection of fruits with less phytotoxicity than application at the rate o f 30 ml/4 nt. Yield of market able fruits increased with occasional exceptions, but damage and loss o f fruits decreased as the hot season (characterised by higher temperatures and longer day-lengths) approached.enNeem seed oil; Soap emulsifier; Control; Tomato; Helicoverpa armigera; Nigeria.Article