Tomatoes are one of the most important vegetables grown in Kenya for income, but insect pests such as Tuta absoluta limit production. Farmers tend to manage pests with chemical sprays, but the sprays harm the farm workers’ health, the environment and food safety. How is non-chemical pest control helping to make a difference?
The Netherlands Ministry of Agriculture, Nature and Food Quality (MinLNV) funded a project in Kenya, led by CABI and Koppert Biologicals Systems Ltd (one of the founding partners of the CABI BioProtection Portal) to show farmers how to use biological control and Integrated Pest Management (IPM) to manage the tomato leaf miner, Tuta absoluta. The IPM programme used a predatory mirid Macrolophus pygmaeus (MIRICAL), the pheromone trap system (Tutasan + Pherodis) and good agricultural practices for the biological control of pests.
Using biopesticides to help farmers grow more tomatoes
The project helped raise awareness about the IPM programme among farmers and extension workers through field demonstrations and training. The trained extension workers then trained additional farmers in their areas of operation and raised more awareness about the available biological methods for controlling and managing the tomato leaf miner.
The work had a positive outcome. A telephone survey carried out among the farmers showed how, following training, they displayed knowledge about the various practices for the biological control of pests, in this case, tomato leaf miner. All of the farmers mentioned using pheromone traps (Tutasan and delta traps), 98% cited the use of sticky traps, and 92% talked about the use of Trianum to manage soil-borne pathogens.
Farmers also mentioned the good use of chemicals to control and scout for pests and spraying only when the pest population had reached economic injury levels. They also talked about reduced pesticide sprays, reduced expenditure, better yields and less labour input. They reported a reduction in average expenditure on pesticides and labour by KES 20,650 (USD 188), and labour for spraying reduced from KES11,649 to KES 6,780 per acre.
After a field demonstration of Tutasan, a tomato farmer from Juja farm in Kiambu county said, “I am excited to see that within minutes many of the Tuta pests have been trapped. This is a product that will help me reduce the production costs I incur. With only three Tutasan traps in my one acre, I have reduced spray frequency to once in two weeks or only when I see presence of pests. This has also greatly reduced the tomato losses and the costs I previously incurred on pesticides and spraying labour.”
Although the farmers highly rated the effectiveness of biological control methods for controlling the tomato leaf miner, technology adoption was challenging because of limited availability at local agro-dealers and limited knowledge about how and when to use the technologies. Also, the price was an issue.
Through surveys, farmers expressed a willingness to adopt IPM technologies, with some trialling those that were demonstrated. The key driving factors leading farmers to uptake the technologies were food safety and the health attributes of biological technologies.
Wider adoption of IPM will need everyone to work together – the manufacturers of the biological products (the private sector), agro-dealers located close to farmers who stock the products and technologies, and extension workers who connect the technology proponents and the farmers themselves. In this way, we can increase biopesticides in agriculture and non-chemical pest control for a more sustainable future.
CABI and the biocontrol industry are working together to support an increased uptake of IPM by providing free information on registered biological products to farmers and growers. This helps raise awareness about the alternative options available to them in their country. In 2020, CABI launched the BioProtection Portal – a free, web-based tool that enables users to discover information about registered biocontrol and biopesticide products around the world.
Read more about the Tuta absoluta project in Kenya on the MinLNV website: Stepping up the fight against Tuta Absoluta in Kenya with safer and sustainable biocontrol products
