International Centre of Insect Physiology and Ecology, Kenya
Zeyaur Khan has made significant contribution to African society by enhancing food security and environmental sustainability through scientific research into the complex mechanisms that govern the ecology of plant–insect interactions and plant signaling in smallholder cereal–livestock production systems, leading to development of ‘push–pull’, an ecological, pro-poor agricultural innovation, and its adaptation to climate change to ensure its long term sustainability; and for leading a research-based extension system for wide-scale dissemination of push–pull, in which natural and social scientists work closely with farmers and extension agents to ensure that research serves the evolution and spread of the technology.
adaptable, productive agricultural systems that are resilient to the risks and shocks associated with long-term climate variability is essential to maintaining food production into the future. Climate-smart agriculture systems needs to protect and enhance natural resources and ecosystem services in a way that mitigate future climate change. We developed the ‘push-pull’ system (www.push-pull.net), a conservation agriculture companion cropping technology for smallholder mixed farming systems which effectively controls serious biotic constraints to cereal production in Africa, insect pests and striga weed, while improving soil health and biodiversity. The companion plants provide high value animal fodder, facilitating milk production. Furthermore, soil fertility is improved due to the nitrogen fixing intercrop and soil degradation is prevented. The environmental and economic benefits of push–pull are most evident when it is part of an integrated crop-livestock system on a mixed smallholder farm, driving the cycling of nutrients between crops, animals and soil. Push–pull contains a legume, desmodium, which adds nitrogen to soil and has a trailing habit, helping conserve soil moisture. It reduces digging and adds to soil organic matter, enhancing the capacity of the soil to sequester carbon. The push-pull system has been adapted to drier and hotter conditions linked to climate change by identification and incorporation of drought tolerant companion crops (http://www.push-pull.net/Climate-smart_Push-Pull.pdf). This climate-smart push-pull directly responds to rising uncertainties in Africa’s rain-fed agriculture due to the continent’s vulnerability to climate change. The new companion crops, can withstand extended periods of drought stress. To date push-pull has been adopted by over 130,000 smallholder farmers in eastern Africa whose cereal yields have increased from about 1 t/ha to 3.5 t/ha. Low-input technologies that address several production constraints and deliver multiple benefits are more relevant for African smallholder farmers but also have useful lessons for agricultural systems in the developed world.