Evaluation of Insecticides for the Management of Insect Pests of Tomato, Solanum Lycopersicon L.

Abstract

Field studies were undertaken in Kumasi, Ghana in 2012 and 2013 to evaluate the efficacy of two insecticides i.e. Lambda Super 2.5 EC (a.i- lambda cyhalothrion) and Cymethoate Super EC (a. i.-cypermethrin and cymethoate) for the management of insect pests on tomato, Solanum lycopersicum L. Lambda Super was applied at 1.5 ml/0.5 L of water whilst Cymethoate Super was applied at 0.25 ml/0.5 L of water. A control plot (water application only) was also maintained. Whiteflies, Bemisia tabaci (Gennadius), thrips, Thrips tabaci Lindeman, aphids, Aphis gossypii (Glover), leaf miners, Liriomyza sp. and the tomato fruit worm, Helicoverpa armigera (Hubner) were the most important insect pests collected on tomato in the area. In 2012, there were no significant differences among the insecticide-treated plots and the control with respect to the densities of B. tabaci, A. gossypii, Liriomyza sp. and H. armigera. Cymethoate Super treated plots recorded significantly lower number of T. tabaci than the control plots. However, in 2013, the control plots recorded significantly more aggregations of B. tabaci, H. armigera and A. gossypii than the Lambda Super and Cymethoate Super treated plots. No significant differences were obtained in the numbers of Liriomyza sp. and T. tabaci among the treatments. In 2012, the insecticide-treated plots recorded significantly higher fruit yield than the control but there were no significant differences among the treatments with respect to percent damaged fruits and mean shoot dry weight in 2013. Lambda Super and Cymethoate Super can be used to manage insect pests on tomato for increased yield.

Keywords: Insecticides, efficacy, tomato pests, population densities, yield