Cassava processing research in Nigeria

Women making gari. Photo by IITA.
Women making gari. Photo by IITA.

Between 2002 and 2010, IITA implemented the Integrated Cassava Project (ICP) to support the Presidential Initiative on Cassava. Under ICP, IITA and its partners successfully introduced and promoted more than 40 cassava varieties to Nigerian farmers, and facilitated the establishment of hundreds of processing centers and fabricating enterprises.

The Presidential Initiative was launched in July 2002. It aimed to create awareness among farmers on the opportunities in the cassava markets worldwide, increase the crop’s area of cultivation to 5 million ha targeting a harvest of 150 million t annually, and earn Nigeria up to US$5 billion every year from export, by the end of 2010.

It also targeted to produce 37.5 million t of processed cassava products annually, such as gari, pellets, chips, starch, and ethanol for local and export markets.

The Nigerian government provided IITA some funds to assist in its R4D efforts and implement the ICP. The project had two components: the Cassava Mosaic Disease (CMD) Preemptive Project which focused on production aspects through breeding and distribution of improved varieties resistant to the virulent Uganda variant of CMD, and the Cassava Enterprise Development Project (CEDP). This promoted the development of enterprises associated with cassava processing.

Through the project, IITA successfully introduced and promoted new varieties to farmers via the national agricultural research system (NARS), especially the Agriculture Development Program (ADPs). It also facilitated the establishment of many processing centers and fabricating enterprises between 2002 and 2010, contributing greatly to the development of the Nigerian cassava industry.

The study
A study was carried out to look at the impact of IITA’s processing research on Nigeria’s staple food system and to draw lessons from these interventions.
It addressed the following research questions:
• What is the level of awareness and adoption of improved cassava varieties, and other production and processing technologies?
• What are the effects of adoption of these production and processing technologies on farming households, their villages, the fabricators, and processors?

The survey was carried out in 70 villages in the four geopolitical zones in Nigeria: South-West, South-East, South-South, and North Central where 952 farmers, 143 processors, and 58 fabricators were interviewed.

Partial budgeting methods as well as micro-econometric evaluation methods were used to assess causal effects based on the changes in outcome and impact indicators in areas with the cassava processing research interventions relative to those without the interventions.

Sorting cassava. Photo by IITA.
Sorting cassava. Photo by IITA.

Technology adoption and benefits: Village level
The results showed that from 2002, the area of land under cassava production had increased by 17% in intervention villages and by 10% in non-intervention villages. Also, the crop was found to occupy more than 70% of total area available for food crops in the sample villages.

Processing machines, such as graters, pressers, fryers, grinders, dryers, and millers proliferated in intervention villages; small percentages of other processing machines, such as boilers and fermentators, were also found.

Cassava produced by farming households was consumed or sold, fresh or processed, with some going to waste. There was a decrease in the proportion of waste over the years in both villages; the same was observed in the sale of fresh cassava roots. On the other hand, the volume of processed cassava increased over the years, suggesting the positive influence among cassava farmers of the government’s efforts to boost production and processing.

Gari and fufu remain the most popular cassava products as they were a decade ago. However, in all villages especially in those where interventions were introduced, odorless fufu, starch, and chips were becoming increasingly popular. Other products such as cassava flour and ethanol were found but in small quantities and only in the intervention villages.

Technology adoption and benefits: Farming households
Cassava was the most important crop grown followed by yam, maize, and plantain/banana, among others. It occupies about 43% of the total cropland in the study areas.

The adoption rate for improved cassava varieties varied among farming households: 74% in intervention villages going up to 94% among those that had attended R4D training and 65% for the other locations.

On the adoption of processing machines, the grater was the most important with 60% adoption in intervention communities and 76% among those that had attended R4D training. It was followed by the presser; the adoption rate for other processing machines was found to be generally low.

Results also indicated that the adoption rate of improved cultivars was significantly greater in intervention villages than in nonintervention villages, with the use of graters for processing cassava having a positive and significant influence on adoption of new varieties. Factors that influenced the intensity of adoption of graters included contact with extension agents and the use of improved varieties, among others. Although adoption of varieties and the uptake of graters reinforce each other, the effect of improved varieties on adoption of graters was found to be stronger.

Given the greater influence of adoption of improved varieties on adoption of processing machines, a sequential approach should be used in technology delivery involving improved varieties and processing technologies. The sustainability of cultivation of improved varieties is ensured by the availability and use of cassava processing machines among the households in the villages.

Adoption of production and processing technologies took place mainly in the last 20 years, particularly in the last decade; 62% of respondents indicated that they started using improved varieties in the last 10 years, whereas 43% had started using the grater and 45% the presser. Responses were similar for other processing machines. This was the period when IITA and collaborators had intensified the push for production and processing technologies in Nigeria prompted by the Presidential Initiative.

The number of households processing cassava into various products had increased by 21% compared with 10 years ago. Gari (57%) and fufu (30%) were the most popular products. The remaining 13% was shared by other products, including cassava flour and starch, among others.

The gross margin values and the benefit-cost (B:C) ratios were greater for improved cassava ($4090) per hectare than for local varieties ($1500). The B:C ratio was 3:9 in favor of improved cassava varieties with the difference being attributed to the relatively high adoption of both improved cassava varieties and various management techniques extended to and used by the intervention villages.

Grinding cassava. Photo by IITA.
Grinding cassava. Photo by IITA.

Cassava machine fabricating enterprises
The study showed that 66% of the enterprises fabricating machines were small scale and that 79% of them were owned by sole proprietors. There were varying levels of awareness on the different types of processing machines with many fabricators using other machines not meant for cassava processing. Graters (85%) and pressers (83%) were the most popular machines fabricated, followed by grinders/millers (59%) and fryers (41%).

IITA-contacted enterprises performed better than the other fabricators. Factors influencing the numbers of machines produced included being a sole proprietor, year of establishment (2003–2010), experience in manufacturing machines apart from cassava-based types, availability of spare parts, contact with IITA/collaborators, and revenue from selling the machines. However, being a sole proprietor and the availability of spare parts had the greatest influence on production.

Processing enterprises
Half of the enterprises interviewed said that they had had contact with IITA/collaborators and 41% had participated in R4D training on cassava processing in Nigeria. The processing machines mainly used by these processors included graters (85%), pressers (67%), fryers (64%), and sifters (34%).

Adoption of cassava products, such as gari, starch, bread, high quality cassava flour (HQCF), instant fufu, odorless fufu, and broiler meal was generally low but still higher for those processors that came into contact with IITA than for those that did not. Adoption was higher for gari (70%), starch (14%), HQCF (16%), and odorless fufu (17%).

An analysis of gari processing showed that it costs less to use “machines only” for processing compared with “manual and machines” and “manual only”. From the cost analysis, $92 was saved when using machines to process 1 t of fresh cassava into gari compared with manual processing.

In conclusion, results indicate that gari is still the most popular cassava product (80% of households and 70% by processing enterprises). Graters and pressers were the most widely used equipment in Nigeria. Although the study found some reduction in adoption due to the decline in the implementation of the Presidential Initiative, most processors and equipment fabricators were still operating in the area. Despite a slow growth, processing increased with a high adoption rate of improved varieties (68%) by farmers. Processing equipment, such as graters and pressers, are now being used widely.

Impact of cassava R4D on smallholder farmers

Does research-for-development (R4D) have an impact on small-scale farmers? The answer is a resounding ‘yes’ based on a series of impact studies on IITA’s cassava R4D work in the Democratic Republic of Congo (DRC) and Malawi.

Cassava harvest in Bungu, Tanzania. Photo by E. Kanju, IITA.
Cassava harvest. Photo by E. Kanju, IITA.

Democratic Republic of Congo
In DRC, an emergency response R4D program was implemented from 2001 to 2009 after the outbreak of the cassava mosaic disease. The study provided hard evidence of a clear impact on household access and participation in markets, adoption of improved crop varieties and crop management practices, plot yields, gross margins, and food security.

Cassava is the number one provider of staple food and wages in DRC, accounting for more than 70% of the annual crop area and supplying around 56% of the calories in the diet (FAO 2010). In 1996, a new, more virulent Ugandan strain of the East African Cassava Mosaic Virus (EACMV-Ug) was detected. By 2000, it had spread to most cassava-producing regions. Most of the widely planted varieties had no resistance to EACMV-Ug and it was feared that the disease would lead to widespread crop losses and food insecurity.

The emergency response program to the outbreak was started in 2001 and aimed at increasing farmers’ income, improving food security, and nutrition, and reducing poverty. It was supported through a multi-donor funding basket.

The first phase was implemented from 2001 to 2006 in the western provinces of Bas Congo, Kinshasa, and Bandundu because there was war in the eastern part of the country. The second phase, from 2007 to 2009, was expanded to include the central and eastern provinces: Equateur, Province Orientale, Katanga, Kasai Oriental, Kasai Occidental, Maniema, Nord-Kivu, and Sud-Kivu.

The first phase focused on the rehabilitation of cassava production through the multiplication and distribution of clean planting material of existing, already released cassava varieties, breeding for improved varieties with resistance to the viral disease and acceptable consumer traits, and improved crop management technologies. The second phase added components of postharvest management.

The program was implemented through an agricultural R4D approach which brought together different R4D organizations into public–private partnerships with clearly defined roles. These included the Programme National Manioc (PRONAM) within the Institut National pour l’Etude et la Recherche Agronomiques (INERA), IITA, the South-East Consortium for International Development (SECID), FAO, Centre d’Appui pour le Développement Integral de Mbankana (CADIM), PACT Congo, community based organizations, farmers’ associations, and village-level farmers’ groups.

Chikwangues, made from fermented and pounded cassava, for sale at Kolo market, Bas-Congo, DRC. Photo by IITA.
Chikwangues, made from fermented and pounded cassava, for sale at Kolo market, Bas-Congo, DRC. Photo by IITA.

The impact
In-depth interviews with participants revealed four stages by which the program interventions had an impact at the farm household level.

First stage: IITA and INERA undertook the multiplication of breeder and foundation planting materials and the development of new varieties, crop management, integrated pest management, and processing technologies. SECID, FAO, and CADIM implemented rapid multiplication and the large-scale distribution of disease-free planting materials, using a quality control system of primary and secondary nurseries to ensure that large quantities of planting materials were supplied to farmers for establishing their crops.
The Bureau Central de Coordination (BECECO), a government clean seed multiplication and distribution program funded by the World Bank, supported the multiplication and distribution of planting materials and farmers’ training. Community based organizations and farmers’ groups established village-level nurseries for multiplying disease-free planting materials of improved varieties, mostly for farmers within their communities but for some in neighboring areas.

Discussions with researchers, implementation staff, and beneficiaries revealed that the program led to the following outputs:
• The formation of strong partnership and networking among researchers in IITA and INERA, FAO, SECID, CADIM, and PACT-Congo, farmers’ associations, farmers’ groups, and small- and medium-scale enterprises.
• Capacity building resulted in the build-up of knowledge, skills, and competencies at the individual and organizational levels for researchers in INERA, extension agents, farmers, farmers’ groups, processors, and equipment manufacturers. Farmers’ field schools helped farmers to gain experience.
• The development and release of disease-resistant improved varieties. When the program started there were no varieties resistant to EACMV-Ug but in 2–3 years, five varieties had been developed. Eleven additional varieties were released between 2005 and 2008.
• Crop management and crop protection technologies were delivered through breeding for disease and pest resistance, releasing predators for green mite control, and refining extension recommendations.
• Processing technologies and institutional innovations for organizing and linking farmers to markets were delivered after the adoption of improved crop management practices and expansion in cassava production in the targeted areas. Small and medium enterprises engaged in cassava processing emerged as a result of the improved processing technologies to expand their operations and market in micro-chips and other products, such as farinha, gari, and starch.

Second stage: During this stage the outputs were delivered to change agents, including INERA researchers, extension workers, NGOs, farmers’ associations, and private sector companies, resulting in changes in their level of awareness, knowledge, and practices.

The major outcomes perceived at the change agent level were as follows:
• Changes in the practice and behavior of INERA researchers, Government and NGO extension agents, processors, and equipment manufacturers.
• Development of supply systems for clean planting materials of improved varieties, advice on crop and postharvest technology management, locally manufactured processing machines and equipment, micro-enterprises engaged in cassava processing, improved quality of cassava flour, better output marketing and logistics of distributing cassava-derived products to urban consumers.
• Tissue culture and institutional arrangements for the multiplication and distribution of planting materials made possible the distribution of a cumulative total of 417,354,633 one-meter stem cuttings of disease-free improved varieties to 3,530,666 households from 2001 to 2008. However, the total planting materials distributed were sufficient for planting only a lower bound estimate of 166,942 ha, or about 9% of the total national cassava area cropped in 2007/2008 using FAO data or 10% using data from the Service National de Statistique Agricole (SNSA).

Third stage: Here, the research products were delivered to farmers, resulting in increased awareness, knowledge, and adoption of improved practices among farm households in villages exposed to the program’s interventions compared to those living in other villages. Respondents interviewed in this study believed that farmers exposed to the program’s interventions acquired new knowledge that mosaic is a disease. To get good yields, growers needed to obtain disease-free planting materials from INERA research stations or NGO multiplication plots instead of neighboring farmers. Farmers acquired knowledge on using phytosanitation to control the disease.

Fourth stage: Respondents perceived that R4D generated synergies between farmers’ access to and participation in markets, on-farm productivity, and the intensiveness in which parcels of land were cultivated. This, in turn, accelerated the adoption of improved technologies and farm-level impacts. Households in intervention villages that participated in the R4D program were perceived to have achieved better yields, higher profitability, and greater food security than those that did not. Processing added value to the cassava produced in targeted areas and the products were increasingly being sold to urban markets.

Bags of dried cassava chips in Mbuji Mayi, DRC. Photo by IITA.
Bags of dried cassava chips in Mbuji Mayi, DRC. Photo by IITA.

The study
Primary data were collected through a questionnaire interview survey in 2009 to a randomly selected sample of households in areas where the program had been implemented and neighboring nonprogram areas. The survey used stratified random sampling to select contact households. A total of 521 households clustered in 52 villages were interviewed.

The study tested three hypotheses on the impact of the agricultural R4D program on farm-level outcomes of interest:
• The R4D program has causal effects on households’ participation in markets.
• The R4D program generates synergies among improved varieties and crop management technologies and encourages their adoption by farm households.
• The R4D program helps households achieve higher plot-level yields, greater profitability, and improved household food security.

The study established that households in villages where R4D had been introduced had significantly higher levels of sales of cassava compared with households in villages without interventions. R4D was also found to increase the probability of a household adopting most of the technology options. There were high correlations among random utility components which provided evidence for the hypothesis that R4D generates synergies among improved technology adoption decisions.

The study showed that households who lived in intervention villages had significantly higher plot yields, gross margins, and food security than those in nonintervention villages. Marginal effects showed that household participation in a farmers’ organization had the most impact.

The study concluded that the cassava R4D interventions were successful in increasing the outcomes. The finding that the R4D program had positive impacts on intermediate outcomes that can be observed in the short term suggests that the approach has potential for long-term impacts on final outcomes. This implies that policymakers can increase the impact of agricultural research on household food security by promoting agricultural R4D approaches together with the development of farmers’ organizations.

Cassava is the second most important staple in Malawi after maize. The two crops supply over 70% of calories in the diet and sometimes replace and complement each other in production and consumption. They are historically intertwined as both were introduced into Southern Africa from Brazil in the 1500s. However, the colonial and early post-independence agricultural policies favored maize and, as a result, cassava production remained insignificant throughout this period.

Women peeling cassava for processing. Photo by IITA.
Women peeling cassava for processing. Photo by IITA.

The situation, however, changed dramatically between 1994–1995 and 2006–2007 when the area grown to cassava more than doubled and production expanded. This was as a result of a combination of factors including (1) realignment of commodity prices in favor of cassava over maize after the removal of consumer and producer subsidies under structural adjustment; (2) development, dissemination, and adoption of improved technologies; (3) extension to popularize cassava; (4) the collapse of input supply, credit, and maize markets; (4) a decline in soil fertility below the economic yields for maize; and (5) high rainfall variability.

The spread of HIV/AIDS may have also contributed by reducing the rural labor supply and replacing high-labor intensive crops such as maize with labor-saving, low-input crops such as cassava. There was an increased demand for fresh and processed cassava in central Malawi as consumers substituted cassava for more expensive maize and wheat products.

A study applied econometric modeling treatment effects methods to estimate the impact of the cassava R4D projects implemented in Malawi in the 1990s and 2000s on the farm-level yield, per capita area planted to cassava, and food security.

Overview of the program
Formal cassava improvement research started in 1930 in Karonga with the collection and evaluation of local varieties for their yield potential and resistance to cassava mosaic disease. Varieties from Malaysia, Java, Kenya, Tanzania, Trinidad, and Ghana were introduced and evaluated.

Notable highlights include the severe drought and famine in the years 1948–1949 and 1949–1950 that led the Department of Agriculture to distribute cuttings as a drought recovery intervention. However, these years were followed by three consecutive good rainfall seasons that resulted in sufficient maize production, large surpluses of cassava which were not sold due to lack of transport, and reduced interest in the crop except in areas where it was already a staple food.

During the 1950s and 1960s, researchers continued to search for mosaic-resistant varieties from the East African Agriculture and Forestry Research Organization. Agronomic trials were also conducted on intercropping, planting time and method, spacing, harvesting, fertilizer use and land preparation, and on pest and disease control. The findings were formulated into recommendations and made available to extension for dissemination to farmers.

Motorized cassava grating machine commissioned by IITA-CFC in Sierra Leone. Photo by IITA.
Motorized cassava grating machine. Photo by IITA.

Postharvest management research was conducted to develop technologies for processing cassava into flour on a large scale by agribusiness companies. In the 1950s and 1960s, the crop began to emerge as a cash crop in the southeastern districts when private traders exported surpluses of dried cassava to East Africa and the European Common Market. At its peak in 1968, the crop was the fifth highest foreign exchange earner in Malawi after tobacco, tea, groundnut, and maize. But the quality of the dried chips was low because of poor processing methods and could not compete with cassava pellets from Thailand.

From 1978, a parallel cassava research program was set up to evaluate materials from IITA. The breeding scheme used at IITA was introduced to shorten the time taken from identification to variety release, multiplication, and distribution of planting materials to farmers. This resulted in the release of second generation bitter varieties tolerant of cassava mosaic and mealybug in 2000. These were Mkondezi (MK91/478), Silira (TMS601428), and Maunjili (TMS91934). In 2002, the national cassava program released two other cassava mosaic- tolerant bitter varieties, Yizaso (CH92/112) and Sauti (CH92/077).

At the beginning of 1985 there was a serious outbreak of cassava mealybug in the main cassava-growing areas but scientists brought the pest under control in the 1990s by exporting and releasing its natural exotic enemies from IITA.

During 1991–1992 and 1993–1994 there were severe droughts followed by low rains in 1994–1995. In response, the national cassava research and extension programs expanded and accelerated the multiplication and distribution of planting materials for cassava and sweetpotato. This was followed by another food security project from 1998–1999 to 2000–2001 which also incorporated postharvest technologies.

The projects resulted in major changes in the organization and implementation of cassava research. The first change was the smart borrowing of IITA’s procedures for large-scale tissue culture, the rapid multiplication of virus-free planting materials, and distribution systems. The systems consisted of farmers’ groups, researchers, extension agents, traders, processors, religious groups, community based and nongovernmental organizations, and policymakers. Also involved were Bunda College of Agriculture, Natural Resources College, IITA/SARRNET, International Potato Center, FAO, United Nations Children’s Fund, and donors (Office of Foreign Disaster Assistance/United States Agency for International Development, United Nations Development Program, and International Development Research Centre.

The first multiplication and distribution project focused on the supply of ‘‘cleaned” cassava cuttings of improved varieties through a quality control system of primary, secondary, and tertiary nurseries, on-farm technology evaluation and dissemination of improved crop management practices, the development of farmers’ organizations, training, capacity building, and networking.

The second project placed more emphasis on postharvest management and market development. The components were implemented as a package in target areas selected as being food insecure suited to cassava production, and suitably located to minimize the costs of transporting materials from primary multiplication sites at government research stations, agricultural colleges, irrigation schemes, and agricultural training centers and from secondary sites in NGO intervention areas. The planting materials were supplied, based on availability and farmers’ requests, to villages through farmers’ groups and distributed through farmer-to-farmer exchange.

Research findings and conclusions
The study found that the cassava R4D program benefited smallholder farmers and generated significant farm-level impact. Using synthetic control methods to control for observable characteristics it showed that by 1995 annual yields in predominantly cassava-growing and -consuming districts first exposed to the program were about 23% higher than they would have been in the absence of the program.

The study estimated an increase of 14% in per capita area cropped to cassava among households first exposed to the program compared with those that were later exposed. The cassava R4D program led to an average increase of 9.1% for the 1997–1998 cross-section, 9.5% for the 2004–2005 cross-section, and 8% in the before and after changes for households per capita area planted to cassava.

Using the Heckman’s treatment effects model to control for observables and unobservables, the study estimated that participation in the program increased the months a household can meet its minimum caloric requirements from home-produced maize and cassava staples by 66% for a randomly selected household, 18% for those actually selected in the program, and 22% for those at the margin of participation.
Therefore, increasing the impact of cassava R4D at a greater scale requires further investments in an adequate supply of planting materials and market development to transform cassava into both a food and cash crop.