Evaluation of Botanical Mixtures for Insect Pests Management on Cowpea Plants

Abstract

Studies were conducted at the Research Farm of the Institute for Agricultural Research, Zaria in 1999 and 2000 rainy seasons to evaluate the efficacy and synergistic activity of extracts mixtures from herbal landraces in reducing pests numbers on cowpea plants and ensuring high yield of grains. The extracts mixed in a ratio 10:10 % w/w included: cashew nutshell + garlic bulb; cashew nutshell + African pepper and garlic bulb + chilli pepper. The results indicated that all the herbal extract mixtures reduced the numbers of the tested insect pests (legume flower bud thrips, legume pod borer larvae and pod sucking bugs) and pod damage as well as increased grain yields by 4 - 5 times compared to the untreated control in the two years of investigation. The synergistic advantage of mixing two different plant species in botanical formulations could play a key role in the renewed effort to control pests of agricultural crops using biopesticides.