Enhancing crop diversity and ecosystem services to promote biological control of fall armyworm in smallholder cropping systems

点击翻译按钮获取中文摘要

Smallholder farming communities in sub-Saharan Africa are particularly vulnerable to crop losses to pests because they generally cannot afford pesticides and as subsistence farmers, they depend directly on the crops for their food security. Fall armyworm has recently invaded and rapidly spread across large areas of Africa, where it has become a major threat to agriculture and sustainable food production. This invasion is a serious and growing threat to food security and livelihoods and already affects at least 400,000 ha causing estimated crop losses worth $3 billion a year. Our project will employ a four-pronged attack on the fall armyworm, utilising the natural defence mechanisms of the crop and companion plants. Firstly, we will assess the natural resistance levels of the maize millet and sorghum crops available to the farmers to determine which varieties would be most robust against the fall armyworm. We will then attempt to drive pests away from the main crop using a repellent intercrop (push), whilst attracting them to alternative locations with trap plants (pull). This technique is known as a "Push-Pull" companion cropping system and is used currently, successfully, against stemborer pests. Finally, we will attempt to utilise the defence mechanism of other companion plants to bring in local predators of the crop pet. These 'early herbivore varieties' are able to detect insect eggs that have been laid on them and emit odours to attract the natural enemies of the pests to the area where the crop is being cultivated. This novel design of pest management based on the four strategies of resist, expel, trap and kill should provide a novel cropping system which can withstand attack by fall army worm and other major pests.Design of such a system requires a detailed understanding of the predators and parasites that are the key natural enemies of the invasive fall armyworm in Kenya. Therefore, a major part of this project will be to understand the current pest and predator relationship where the crops are being grown. Once determined, we will be able to test how such companion cropping and early alert crops could mitigate crop losses to the fall army worm using crops that are readily available to the farmers in Kenya. Such a system could only be generated through close partnership with the local farmers. We will co-design solutions with them so that that we can be assured from the onset that the novel cropping system that is created is not just appropriate for their requirements but can be feasibly implemented with the resources available to them.