Maize-Legume Intercropping in Fall Armyworm Fight Yielding Results

By Dorcas Kabuya Chaaba

It is in the public domain that Fall Armyworms (FAW) have continued to cause devastating effects on farmers' economic livelihoods in Africa since the outbreak was reported in 2016. Chemical control was indeed the first resort after the outbreak, and a lot of resources were spent on procuring pesticides.

Agricultural researchers have not folded their hands to figure out what other best methods could be economically viable in controlling this pest. Different control methods such as using natural enemies, neem-based products, legume-maize intercropping, sand and ash have been used to try and contain the FAW, bringing the whole array of technologies into what is called FAW Integrated Pest Management.

Ministry of Agriculture, working with the International Centre of Insect Physiology and Ecology (ICIPE), has been implementing a community-based Fall Armyworm Monitoring, Early Warning and Management programme. As part of the programme, intercropping trials were set up in Chilanga, Chongwe, Chirundu, Livingstone and Kazungula districts of Zambia using the farmer field school approach to observe and test the efficacy of intercropping in the FAW fight.

ICIPE Head of Technology Transfer Unit, Saliou Niassy, noted that the programme's goal is to improve farmers' livelihoods and disseminate information on Integrated Pest Management (IPM) strategies in different agricultural organizations, including ICIPE, had developed. Dr Niassy noted that among the techniques that were developed include the use of natural enemies, push-pull, use of bio-pesticides, maize-legume intercropping as well as monitoring of the pest for timely action could be taken. "Working with the Ministry of Agriculture in Zambia, we rolled out the maize-legume intercropping programme in eight districts for farmers to observe the results using the Farmer Field School (FFS) approach," he said.

Dr Niassy further added that it was important to undertake the programme, adding that since the outbreak of FAW in 2016, many farmers in Africa whose livelihoods depended on maize were devastated by the impact of the pest. "Before we could implement the programme among farmers, we so it fit to explain to the farmers the biology and ecology of the pest and how it works within the environment because many framers did not know that it's the female moth that lays eggs in their fields at night," he stressed. 

Dr Niassy noted that he was elated that most farmers could explain the differences observed between a maize-cowpea intercropped field and a maize mono-cropped field. "Most farmers can explain the principles behind maize-cowpea intercropping and its efficacy compared to their traditional monocropping. Farmers have seen that yields have increased due to reduced FAW pest attack, and they are looking forward to expanding the area for maize-legume cultivation in the coming farming season," he narrated.

Demian Mabote Ndalamei is an Agricultural Research Officer from Zambia Agricultural Research Institute (ZARI) and explained that intercropping is the growing of a mixture of crops on a piece of land. Mr Ndalamei stated that the practice of intercropping maize with a legume like cowpea provided food and shelter to FAW's natural enemies and increased the population of beneficial insects and efficiency in controlling FAW pest populations. "When farmers intercrop maize with a legume, the maize grows with vigour and can recover quickly from damage because legumes fix nitrogen in the soil. In addition, cowpea maintains moisture. If there is a bit of drought because of intercropping, the chances are that the maize will recover provided the drought is not prolonged," he emphasized.

Mr Ndalamei further reported that when farmers intercrop maize with cowpea, the legume produces a scent which suppresses or repels the smell from the maize plants. This, therefore, controls the FAW population because the cowpea smell is very hostile to the female FAW moth making it difficult for eggs to be laid in the intercropped field. While Emma Hangombe is a member of the FFS in Nakachenje Agricultural Camp in Chilanga District, she has taken it upon herself after seeing the benefits by disseminating the information to her Seventh Day Adventist Church members. Mrs Hangombe stated that she learnt that the FAW insect pest lays eggs underneath the leaves in the maize fields during the night. "Using the Zig-Zag method of scouting, we discovered more FAWs in the monocropped field in the intercropped field. This prompted me to share this good news with other farmers in my local church who were not part of the FFS," she recounted.

Moses Sibanda is another farmer who has witnessed the effectiveness of maize-cowpea intercropping. "We received visitors through our Camp Officer and were trained on the benefits of intercropping maize with cowpeas. We set up a two demonstration plot intercropping two rows of cowpea after two rows of maize while in the other field only maize was planted," said Mr Sibanda. He further explained that as the crops were growing, we observed more benefits in intercropping than mono-cropping, adding that there were more FAWs in the mono-cropped field.

Hengiwe Phiri, the land owner where the FFS was set up, noted that engaging the affected community in FAW management was a step in the right direction and urged other agricultural organizations to emulate ICIPE. Ms Phiri stated that engaging farmers in conducting trials where they can observe for themselves what is happening increases the adoption rate rather than just imposing the technologies on the farmers.

Meanwhile, Sila Mwape, the Block Extension Supervisor, noted that through the programme implemented by ICIPE and the Ministry, the farmers had seen that intercropping lessens the population of FAWs and provided the households with food and nutritional security. "Farmers have seen that intercropping lessens the usage of chemicals that can be harmful to humans and the environment," Mrs Mwape added. Intercropping Maize with a legume is one method that has proven to be effective in the fight against Fall Armyworm, farmers in Chilanga's Nakachenje Agricultural Camp have attested to this fact.

This programme is sponsored by the United States Agency for International Development (USAID) and the European Union (EU). It is implemented in Kenya, Ethiopia, Uganda, Tanzania, Rwanda, Malawi and Zambia.

 The author is an Agriculture Information Officer at the National Agricultural Information Services. She is also CCARDESA Information, Communication and Knowledge Management (ICKM) focal point person for Zambia