Push-pull: A novel IPM strategy for the green revolution in Africa

Abstract

Africa faces serious challenges in feeding its population, mainly due to poor yields of cereals that serve as both staple and cash crops occasioned by insect pests, weeds, and poor soil fertility, and more recently effects of climate change. A novel IPM approach dubbed push-pull has been developed and implemented in eastern Africa, based on locally available companion plants, that effectively addresses these constraints resulting in substantial grain yield increases. The technology involves intercropping cereal crops with stemborer moth repellent crops (push), the forage legume desmodium or molasses grass, and planting the attractive Napier grass (pull) as a border crop. Desmodium is very effective in suppressing striga weed while improving soil fertility through nitrogen fixation and improved organic matter content. The companion plants provide high-value animal fodder, facilitating milk production and diversifying farmers' income sources. The technology, currently practiced by over 55,000 farmers in East Africa, has been adapted to dry conditions associated with climate change by identifying and incorporating drought-tolerant companion plants. The development of this technology, its benefits and subsequent efforts to expand its geographical suitability and effectiveness are described.