Evaluation of Synthetic Insecticides for the Management of Helicoverpa Armigera Mill in Tomato Production

Abstract

This study was conducted to evaluate the efficacy of synthetic insecticides in managing Helicoverpa armigera Mill in tomato production. The experiment was conducted during the major and minor tomato growing seasons at the Sekyere Kumawu and Asante Akim North districts in Ghana. The experimental design was a 3 x 5 factorial randomized complete block with four replications. Four insect pest control regimes were evaluated for their effectiveness in controlling the tomato fruit borer. Three tomato varieties were used in this experiment. The results showed that, significantly, higher marketable fruit yields were obtained on the sprayed plots than the control plots. In general, the variety “pectomec” suffered the highest yield loss on the water sprayed field, followed by UC 82 and lastly, power rhino, although all the varieties suffered losses greater than 50%. This shows that none of the varieties used for this study is completely resistant to Helicoverpa armigera. Yields were generally higher in the major season (March-July) than in the minor season (September-December) for pectomec and power rhino. The best insecticides are Oxymatrin (2.4%), Lambda-cyhalothrin (2.5%) and Dimethoate (400g/l) +Cypermethrin (36g/l) in descending order. Contrarily, UC 82 had low yields in the major season than in the minor season. The study recommends that Helicoverpa armigera Mill should be controlled with pesticides to improve yields of tomato.