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Published by Dr Josphert Kimatu

Transforming the traditional cassava production systems into a sustainable food security strategy and value added industrial products for rural development


Globally between 1980 and 2011 the global area with harvested cassava has expanded by 44% from 13.6 million to 19.6 million ha making it second only to maize but ahead of rice, wheat and potatoes. However, this multipurpose crop, is seriously underutilized in Kenya. It is a plant which can be harvested in all seasons, can tolerate acidic soils and grow in relatively poor soils. It produces more carbohydrate per area compared to cereals like maize. Most of its parts can be used by man. For example, the roots are rich in carbohydrates while the leaves are rich in minerals and vitamins. The stem can be used as a planting material, firewood and even a substrate for mushroom production. Value addition can be employed in the processing of cassava to make it a poverty eradicator in the rural. The starch from cassava produces high quality flour, glue, industrial and textile starch, ethanol etc This research aims at screening high yielding, pest resistance, drought tolerant and early maturing increasing cassava varieties. A proposed technology shall be employed for fast production of new cultivars which shall be distributed to farmers. Production efficiency, maximizing productivity, water efficiency utilization, pest management, value addition, biofortification, and germplasm breeding shall be done. It shall involve farmers farm training of best practices in this technologyat all stages of the crop chain from farm to table.



The 2013-14 estimate of world cassava (Manihot esculenta) production was over 277 million tons from an area of about 20 million hectares with an average productivity of about 13.85 tons/ha. The world’s largest producers are Nigeria (20%), Thailand (11%), Indonesia (9%) and Brazil (8%) in relation to the area cultivated. Thailand is the largest world exported of cassava. However, India has the highest productivity of 34.95 tons/ha).  Cassava has been found to possess characteristics that make it very attractive to smallholder farmers in rural areas. This is more so where soils are poor and low unpredictable rainfall is the norm. Rural farmers like it for its cheap available stem cuttings, its tolerance to acidic soils and its ability to associate with mycorrhizae for survival in drought conditions and nutrient deficient soils. It also produces two glycosides which are converted to Hydrogen cyanide (HCN) to deter herbivores though it can also be poisonous to humans upon ingestion. However, farmers have known ways of processing cassava to reduce HCN. These processes include peeling, washing, grating, pressing, disintegration, sifting, milling, screening, packaging and storage. Alongside, drying, fermenting and harvesting methods. It is these attributes that make cassava a food security crop for achieving regional and national food goals.

Justification of the research

Cassava is a plant which can make a region to be food secure in just two years. This is because of the following unique features of cassava;

  1. It is drought tolerant compared to the present major staple foods in the ASALs which is very ideal for Kenya achieving the Vision 2030 and Africa achieving the STI agricultural goals.
  2. It is a high yielding crop. It can yield more than five times per unit area compared to than maize. Through breeding for high yielding, disease resistance and high-quality starch and to do participatory selections of cassava varieties productivity can be increases and stabilized.
  3. It contains 80% carbohydrates, we can get 3600 calories for cassava, 3700 calories from maize and 3400 calories from wheat. Hence cassava is a very competitive source of energy. Cassava produces more carbohydrates than maize per area.
  4. Cassava leaves are edible and great sources for vitamins, proteins and minerals. This is more so from new varieties. They can also be mixed with milk and ground to make a highly nutritious vegetable meal for children and mothers in ASALs.
  5. The inedible parts like peels can be utilized as fish, poultry and cattle feed.
  6. It has many industrial uses, like in making of starch, glue, ethanol production, food industry etc
  7. Cassava is easy to cultivate, propagate and cheap to manage.
  8. The industrial demand for Cassava can be a source of income for families in ASALs and provides a solution for food insecurity. This can then farmers to diversify their diets as cassava requires very little input in fertilizer. The cassava industry shall be a source of employment and branding for locals, instead of women carrying concrete in remote areas away from families. Cassava starch is globally priced higher than maize. The prices of cassava starch are predicted to continue increasing. Hence it forms a very feasible avenue for rural industrial development.
  9. Education on the processing and handling of cassava can alleviate the fear of HCN poisoning in the sub Saharan region.
  10. Cassava flour can be used for baking bread and other confectionaries like biscuits and doughnuts. This can save the sub Saharan region billions of dollars by reducing importation of wheat.
  11. Technology has been applied to increase the nutritional value of cassava. For example, Biofortification can increase content of carotenoids a precursor of Vitamin A, Iron and Zinc. While fermentation have been found to increase the protein content of cassava by ten-fold.
  12. Cassava can reduce the risks of crop failure in ASALs and it can be a shock absorber for external risk factors like climate change. This is because cassava is more climate resilient compare to sorghum, maize, millet, potatoes and wheat.
  13. Little research has been done in the sub Saharan region as compared to rice and wheat. This is because it is not common in developed countries who have advanced research in their staple foods. Cassava can be the only crop which can be grown in the rough terrain and hilly small-scale farms where it is difficult to employ mechanization. Kenya has had a lot of deforestation which has led to a lot of soil erosion. Cassava can be a remedy for soil erosion from farms as it holds the soil in both during the rainy and dry seasons.
  14. Cassava shall form the base for urban food security in the sub Saharan region due to the continued increase in cereal prices and the diseases thereof. The supply of maize in urban centers is currently not sustainable. Kenya has to import maize, but our neighbours in Tanzania do not need to import maize. This is partly because Tanzania has high production of cassava flour which supplements maize flour in supermarkets.
  15. The circadian clock of the cassava seems to be flexible as the stem cuttings can be planted throughout the year and can be harvested throughout the year.


The research aims to:

  1. Introduce a sustainable intensification of cassava production to increase varietal productivity through an ecosystem approach and develop a rapid cassava multiplication protocol.
  2. Increase income from cassava for rural farmers through value addition technologies by integrating small scale farmers and industry
  3. Combine tradition knowledge with modern techniques through farmer participatory research to reduce HCN through proven post-harvest processing protocols.
  4. Establish a cassava gene bank in South Eastern Kenya University of the landraces and improved varieties for sustainable supply to farmers and germplasm improvement.
  5. Isolate, culture and identify vesicular arbuscular mycorrhizae and endophytes which shall be inoculated to supplied cassava cuttings to make them nutrient absorption efficient.
  6. Identify the natural enemies of cassava including parasitoids, predators and entomopathogens and investigate the mechanisms of biological control of pests.
  7. Promote, produce, brand and determine the nutrient components of various value addition items like starch, bread, biscuits, crisps, vegetables etc.
  8. Produce and analyze fish, poultry, and cattle feed nutritional quality from cassava peels using yeast fermentation.
  9. Carry our biofortification of cassava to increase the Vitamin A, Iron, and Zinc in the starch.
  10. To produce higher yielding genotypes through the development of molecular markers associated with specific genes, screening for pest resistance, leaf physiology, and growth parameters in genetic breeding programs.
  11. Developing an online app for cassava diseases as a farmer early diagnostic aid.

Requirements for the project

  1. Cassava peeler, presses and chipper machines, installation and maintainace, this shall be acquired from Tanzania who are already (since 1993) having cassava flour factories from small scale farmers. There small-scale farmers are locally producing cassava cakes in small village groups.  Then the products from the groups are collected to the main factory. The contact for Intermech Engineering LTD, Morogoro is at www.intermech.biz. They have sold over 450 chippers. Sold 250 grinders, more than 250 pressers of 5-10-ton power.
  1. We shall use a strategy that shall be able to break even. For industrialization, we shall require constant supply of quality and quantity of cassava roots from farmers. like 50 tons of cassava tubers per month. We shall use a rotational breeding and nursery production strategy of high yielding cassava varieties which shall be harvested at different times. In SEKU we shall have a reserve stock in 20 acres. A solar dryer and flush dryer shall be introduced as dependency of sun drying of cassava can reduce quantity especially during the rainy seasons. We shall use hydraulic presses and their accessories to remove water from the grated cassava before quality analysis and packaging material, biofortification and branding of final products. There shall be storage rooms for the cassava, collection vehicles, drying vessels and yards and laboratory analysis equipment for HCN, Carbohydrates, vitamins, minerals, proteins and fats in the value chain. We shall involve youth and women in the whole cassava value chain; pre-planting, production, logistics, processing, marketing and consumption so as to reduce the poverty, crime, restless and violence among them.


The planting material of cassava stems has been approximated as 60 bundles per hectare. Fertilizer shall be applied at 9-12 bags/ha depending on soil condition. There shall be analysis to reduce the use of agrochemicals: pesticides, herbicides. Wooden boxes shall be used to grow the cuttings to ensure full growth during the start of the rains. There shall be varietal selection and the characterization of cassava genomes. The breeding shall focus at adaptation to specific agro-ecologies, various cropping systems and industrial end-uses needs. The other agronomic traits to be checked shall be yields, pest and drought resistance. The routine of multiplication of cutting and later the distribution of disease-free planting material of screened varieties shall be used to develop a protocol for farmers as a key for sustainable intensification.

Water management during production

cassava can grow in areas that receive up to 400 mm of average annual rainfall although water supply can increase the yields. This research shall aim at optimizing ASALs rain in the cassava production. This shall require careful observation and recording of planting dates, cutting planting methods, positions, soil management practices that help to conserve soil water. We shall employ drip irrigation shall be employed in the research to accelerate seeding and plantlets growth.

Combining ecosystem processes in cassava production

The research shall combine ecosystem processes and the judicious use of mineral fertilizers like NPK. This shall form the basis of a sustainable crop nutrition system. This shall make the soil to be microorganism friendly and keep biological prey predator relationships balanced. In order to reduce the loss of soil nutrients, zero tillage and reduction of erosion shall be employed. This shall aim at maintaining soil structure, aggregation, soil stability and drainage. Crop cover using various techniques shall be employed. This shall include plastic mulch, groundnut covers and other legumes like green gram. The aim shall be to increase and speed up the rate of cassava canopy cover. This is to avoid the mistake of green revolution which caused an increase of production at the expense of the environment making it not sustainable. We should not erode biodiversity, pollute the air and soil and water and cause pest increase in any crop system.

Developing a smart phone app and an online app for cassava diseases diagnostic aid

The variuos modes of delivering and accessing extension-related information for farmers are changing. There is generally a reduced extension education resources in the budget. Furthermore, there are changes in farmers’ expectations have led to less standardized, face-to-face meetings. More farmers are more comfortable in mobile phone distance-learning interaction approaches. We shall develop a web-based pictorial diagnostic key tool for cassava diseases. This tool shall aid users in identifying, estimating, comparing and analysisng cassava infestation. This shall eventually assist in having a reliable epimediologally based interventions. we plan to have a smart device application, such as an app for iOS or Android OS and also design a website because of the ease of development and maintenance.

The harvesting, post-harvest and value addition techniques

Various techniques shall be employed to reduce root colouring and perishing after harvesting. This shall include soaking into salt, lemon, etc. to reduce post-harvest physiological deterioration.  The peels research shall be introduced by using yeast to reduce HCN and increase protein contents and vitamins. The roots shall be processed and tested as either granulated flour, or into fine high-quality cassava flour which shall be blended with various other flours like wheat in baking. The root starch quality shall also be tested for various industries like glue, food, textile, ethanol, biofuel. The leaves content shall be analyzed for vitamins, minerals at various ecological zones and compared with soil tests. The peels shall be tested in livestock feeds.

Sustainable cassava development agenda

     This shall be a farmer participatory research, involving field farmer production systems. Some stakeholder engagement meetings shall be done to get feedbacks at the start and the end of  each growing season.


We are looking for a funding of kshs 17,992,200 or $179,922  to implement the proposal. 

Justification of equipment:

The equipment’s requested are for peeling the cassava and grating the cassava in the preliminary stages are mainly to eliminate the reducing Hydrogen Cyanide. This has been the main fear of cassava consumption in the south eastern region. However, the processing equipment shall increase the surface area for rapid decomposition of HCN from its precursor glucosides and also enhance fast drying of the pellets. The solar heater is to reduce losses of the cassava cutting during rainy reason when the weather is cold. The growth chambers are to grow the cassava hybrid grown from cassava seeds so that they can be hardened faster without viral infection at the tender age. Most of the water and septic tanks are to enable the processing of cassava products to meet KEBs standards for human foods certification criteria. The cassava varieties shall need more attention in the germplasm collection and propagation stages of the protocol development as well as during the biofortification and value addition stages.

6.0.  References

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