COMPARATIVE EFFICACY OF Tephrosia vogelii and Moringa oleifera AGAINST INSECT PESTS OF WATERMELON (Citrullus lanatus Thumb)

Despite the fact that synthetic insecticides are fast acting, they constitute environmental hazard thereby necessitating the use of ecologically based alternative such as plant based insecticide. This experiment was conducted during the late and early planting seasons of 2011 to determine the insecticidal efficacy of Tephrosia vogelii and Moringa oleifera extracts at three tested concentrations (5, 10 and 20 % v/v) against insect pests of watermelon. The experiment was set up in a randomized complete block design with three replicates. The results showed that M. oleifera extracts had 62 % reduction of Phyllotreta cruciferae compared with T. vogelii which had 45% control. However, T. vogelii extracts had 64 % control of Diabrotica undecimpunctata and Bactrocera curcubitea but M. olefera extracts had 50 % control. The plant extracts proved effective against studied insects when compared with untreated plots. However, the effectiveness of the two plants extracts were concentration dependent. Therefore, the two plant extracts can be used in the control of insect pests of the watermelon. 1