High yielding plant teams renew farmers’ interest in legume intercropping in Kenya
By John Ochieng Otieno, with contributions from Milton Esitubi, Mary Kinyanjui, Charles Magare, Emmanuel Makatiani and David Odee.
Nyabeda village farmers, Siaya County, Kenya
There is no better place for testing and demonstrating farmer innovations with plant teams than Nyabeda village in Siaya County – located in Kenya’s Lake Victoria region. After all, the predominantly maize (Zea mays) and common bean (Phaseolus vulgaris) growing Nyabeda villagers have been at the heart of various agroforestry technology developments in collaboration with national and international organisations for nearly four decades now. These technologies have transitioned from traditional farming systems to the contemporary plant teams – with the help of indigenous knowledge and innovations. They integrate legume nitrogen-fixing trees, shrubs or herbaceous species in cropping systems in order to improve soil fertility and health for food production. According to the latest population and demographic data from the Kenya National Bureau of Statistics (KNBS, 2019), Nyabeda village has a population density of about 320 persons per square kilometre. The average farm size is 1.3 ha per household. Food security is therefore of great priority.
Tacit knowledge of legume technologies
In early 2018, we held a stakeholders’ workshop as part of the DIVERSify Horizon 2020 project at the Kenya Forestry Research Institute’s Lake Victoria Basin Eco-region Research Programme (LVBERP) Maseno Centre to identify tacit knowledge, local innovations, strategies and farmer best practice on cropping systems. The participants listed the following technologies and innovations: improved fallows, biomass transfer, mixed cropping /rotational intercropping, integrated soil fertility management and ‘push and pull’. In Nyabeda, improved fallows is the most widely used cropping system, and the local farmers practice various forms of the technology to suit their needs. Improved fallows involve the planting of fast-growing fallow species as part of a crop-fallow rotation for rapid replenishment of soil fertility – usually selected for their nitrogen-fixing abilities.
Demonstration trial- designed and worked with Nyabeda village farmers
A demonstration trial was established in Nyabeda Primary School (0°07’N, 34°24’E, 1330 metres above sea level), the most central and accessible location for the more than 2000 persons who live in the village. The trial, which also doubled as an experimental Case Study in the TRUE Horizon 2020 project, was carried out during the short rains between September and December 2018, and the long rains between March and July 2019. The design and treatments were informed by the various local farming practices, incorporating - the white tephrosia (Tephrosia candida) improved fallow technology to enhance maize and bean production. Local farmers and the school participated in the management and assessment of the trial. Nyabeda receives mean annual rainfall of 1500-1900 mm and annual temperature of 22°C to 24°C. The soils have low pH (pH 5.9), nitrogen (0.12%), and are classified as Ferric Acrisols.
The trial had the following treatments:
Monocultures of maize, common beans and white tephrosia.
Mixtures of maize+common beans, maize+white tephrosia, white tephrosia+common beans and maize+common beans+tephrosia. Mixed species treatments were established by planting alternate rows.
Rhizobial inoculation and inorganic fertiliser application at the rate of 120 kg/ha of DAP/NPK, versus no inoculation and fertiliser controls. Bespoke rhizobial inoculants were developed and used in the inoculation of the legumes - white tephrosia and common beans.
Planting densities were 266,667 plants/ha for common beans, and 61,538 plants/ha for maize and tephrosia. After harvesting the short rains crop, white tephrosia foliage and pods was uniformly spread and incorporated back into their respective plots, in readiness for the long rains maize and common beans planting.
(A) Luxuriant maize crop growing on tephrosia improved fallow trial plot in Nyabeda Primary School; (B) KEFRI’s Milton Esitubi and Mary Kinyanjui (with green tops) and participating farmers delivering maize to the Chairman of Board of Management, Timothy Osodo (standing front right with cream top) in support of the school feeding programme. Photo credit: C. Magare.
Key findings and outcomes of the demonstration
The highest maize grain yield was 6.3 t/ha grown on tephrosia improved fallow, and without inorganic fertilizer. This is nearly double the average yield for Siaya County.
Use of tephrosia fallow and intercrop reduced the incidence of the parasitic witchweed (Striga hermonthica) on maize.
The highest common bean grain yields of 3.4 t/ha was obtained with common bean grown as a monocrop during the short rains. This yield was also above the average common bean yields for the county.
While receiving 200 kg of maize grain harvested from the demonstration plot in support of the school’s feeding programme, John Osodo, the Chairman of the Board of Management, said: “We are thankful to KEFRI and the EU project for having established the trial within the school for purpose of learning and knowledge sharing on farming technologies among the community of Nyabeda village.'' More than 20 local farmers were directly involved in the management and assessment of the trial. They will play a crucial role in sharing the knowledge among the more than 500 farming households in the village, and yonder.
For further information regarding this article, contact John Ochieng Otieno on: firstname.lastname@example.org.
John Ochieng Otieno is Biotechnologist with the Kenya Forestry Research Institute. He has extensive experience in research project implementation, stakeholder engagement and knowledge exchange. He is a DIVERSify project ‘Buddy’, and TRUE project scientist. He holds a Bachelor of Science in Agricultural Biotechnology.