Theresa Ampadu-Boakye, IITA-Nairobi. Edward Baars, IITA-Abuja. Fred Kanampiu, IITA-Nairobi. David Ngome, IITA-Nairobi.
The Putting Nitrogen Fixation to Work for Smallholder Farmers in Africa (N2Africa) project, funded by the Bill & Melinda Gates Foundation, is working to expand the farm area planted to grain legumes (common bean, cowpea, groundnut, chickpea, faba bean, and soybean) and enhance their yields to improve smallholder farmers’ incomes and food and nutrition security.
At the end of Phase 1 (2010-2013), the project had developed several products including certified seeds of improved varieties, inoculants, legume fertilizers, and laborsaving tools and services that benefited some 225,000 small-scale farmers in DR Congo, Ghana, Kenya, Malawi, Mozambique, Nigeria, Rwanda, and Zimbabwe.
The project went into a second phase (2014 to 2018), focused on scaling proven technologies and ensuring sustainable input and output supply chains for farmers to buy and use the products developed and tested under Phase 1. Three new countries–Ethiopia, Tanzania, and Uganda, were added to the project in the second phase as part of the project’s core countries together with Ghana and Nigeria. The six other countries became Tier-1 countries that consolidated earlier achievements.
Evidence from agronomic research
Diagnostic, demonstration, and adaptation trials
Fifty-three diagnostic trials were established in 2017 responding to key research questions, mostly about nutrient management. A total of 1,454 demonstration trials were established focusing on disseminating a single technology or a combination of technologies. The demonstration trials showcased the best-bet technologies to many farmers and were used to collect data on their performance. Evaluation of these technologies was conducted with farmers to ascertain their preferred technologies and the information was used to reshape the technology packages they would use. Adaptation trials are small trials established and managed fully by farmers (with limited backstopping) to determine how they adapt technologies to their settings. Inputs that farmers received for these trials consisted of an improved legume variety with P-fertilizer and/or inoculants. In 2017, farmers established 25,071 adaptation trials. A selection of these adaptation trials was monitored to assess the performance of the technologies under heterogeneous farmers’ conditions and management. Table 1 gives an overview of the number of trials established in the Core and Tier 1 countries in 2017.
In the adaptation trials, mean legume yields varied from 300 to 2,600 kg/ha on the N2Africa plots, and from 400 to 2300 kg/ha on own legume plots (10 × 10 m plots) (Table 2). Mean yields significantly increased on all N2Africa plots compared with the own legume plots, except for Uganda. Farmers generally saw an increase of 300 to 800 kg/ha on the N2Africa plot compared with their own legume plots. In relative terms, farmers growing cowpea or bush bean in Tanzania and soybean in Nigeria, on average more than doubled their yields. Generally, more than half of the farmers had a yield increase of >50% (except for Uganda). Note, however, that there is an experimental error associated with the use of measurements on sub-plots which may inflate the proportion of fields with more than 50% yield gain.
The lack of increase in legume yields on the N2Africa plots in Uganda may have been caused by dry spells in parts of the country, which limited the number of trials that could be harvested and depressed legume yields (cf. yields of bush bean and soybean). The positive effect of the use of P-fertilizer in adaptation trials of cowpea was larger in Eastern Tanzania than in other parts of the country, suggesting that P-fertilizer is especially recommended on cowpea in this area.
Recommendations for best fit technologies
The combined results of yields and farmers’ evaluations of diagnostic, demonstration, and adaptation trials over multiple seasons led to the development of best-fit recommendations for the different legumes in the core countries (Table 3).
In Ghana, the New Yara Legume (NYL) fertilizer (NPK, Ca, OMg2, OB) was tested against TSP fertilizer. In all three legumes, NYL resulted in larger yields than TSP (see examples for soybean and groundnut in Fig. 1). Yields of cowpea were also significantly larger with 1250 kg/ha for TSP and 1380 kg/ha for NYL (P < 0.05). The difference in performance of cowpea and soybean varieties in different parts of the country in both diagnostic and demonstration trials led to tailored recommendations about the suitability of varieties for different parts of the country. The early maturing soybean variety TGX 1985-10E was outperformed by the other two improved varieties in terms of yield, but was still considered suitable for late planting.
Agronomic studies to develop recommendations for soils non-responsive to inoculation and P-fertilizer showed that an additional application of 30 kg/ha of S (sulfur) was recommended for chickpea production in Northern Ethiopia, while a combined application of K2O (60 kg/ha) and lime (4.6 t/ha) was recommended for soybean production in acidic soils in Western Ethiopia.
Bush bean in Northern Tanzania with a combination of (N)PK fertilizer and inoculants resulted in the highest yields. The highest yields of groundnut were attained with a combined application of farm yard manure, Minjingu Rock Phosphate (MRP), and a little gypsum. Farmers also ranked this treatment highly as these inputs are readily available and less costly to smallholder farmers. Aflasafe, a biocontrol agent for controlling fungi producing aflatoxin was added on top of fertilizer treatments to assess the impact of agronomic practices on its efficacy. There were higher levels of aflatoxin contamination on groundnut from plots that were not treated with Aflasafe and no difference between the two biocontrol methods as they both reduced aflatoxin levels by up to 95%.
In Uganda, diagnostic trials were conducted to identify the nutrients needed to close the yield gap related to soil fertility, as previous trials had shown that neither application of P + inoculation could close yield gaps of soybean nor manure + P close yield gaps of climbing bean. In soybean, inoculation and lime resulted in significant increases in yields compared to the control or lime alone; and yields of inoculation and liming with P were significantly better (1526 kg/ha) than without P (1,383 kg/ha). The addition of K, N, Mg, Ca, and micronutrients did not result in a significant change in yield until manure was added, resulting in a maximum yield of 1872 kg/ha. The economic viability of the nutrient combinations particularly inoculants alone, inoculants + P, and inoculants + P + manure—should be assessed and related to farmers’ capacity to purchase. Climbing bean grain yields showed significant responses to lime application and combined application of lime + P.
This reiterates the need to manage soil acidity in the highland areas to improve climbing bean
productivity. It could also explain the responses to manure and P application in some demonstration trials in previous years; manure probably plays a liming role. The liming contribution of manure needs to be evaluated, as manure could be an alternative option to agricultural lime in climbing bean production for those who have access to it.
In 2017, we also captured the “learning pathways” that have led to changes in demonstration trials from 2014 up to 2017; describing the main reasons behind moving from best-bets to bestfits1. Common reasons to discard varieties in demonstrations were poor yields (often the result of increasingly irregular rainfall patterns). Introduced varieties were therefore in most cases selected based on their drought tolerance and better yields. For groundnut, there was also a clear selection towards varieties with high oil content and with a good taste to accommodate market demand. Changes in inputs described specifically for 2017 were that Legumefix was added to bush bean in demonstration trials in Tanzania because results elsewhere (Ethiopia, Rwanda) indicated a response to inoculation in common bean. In Ghana, TSP was replaced by NYL for fertilizing cowpea and soybean. In Uganda, the herbicide Beans Clean was introduced in 2015 to produce bush bean, climbing bean, and soybean to reduce the labor intensity of weeding. Some weeds persisted after the application of Beans Clean, so a stronger, broad-spectrum glyphosate herbicide was introduced in 2017 to be used in combination with or instead of Beans Clean.
Feedback from farmers was very often the basis of changes. Evaluation with farmers is clearly necessary to steer practices towards bestfit within a regional context with its specific weather and market conditions. Other lessons learned from capturing these changes were the need for varieties that are more tolerant to changing and irregular weather conditions while still being high yielding and marketable. The availability and accessibility of legumespecific inputs such as certain rhizobium strains (Ethiopia), TSP (Tanzania, Uganda), or DAP (Ethiopia) were often a problem, stressing the importance of networking with partners and lobbying policymakers.
To transform agriculture in Africa, evidence on the effectiveness and impact of the dissemination
approaches needs to be applied; this is an important research-for-development milestone of the N2Africa project since it is also a learning grant. Effectiveness of dissemination means smallholder farmers have the capacity to use and adapt the technologies. To create impact, this capacity needs to be complemented with a sustainable input (certified seeds, inoculants and fertilizers) and output supply.
Effectiveness of dissemination approaches
N2Africa and its partners continued in 2017 to reach smallholder farmers by raising awareness and conducting training on the use of technologies through various dissemination activities. These comprised field demonstrations, adaptation trials, field day packages, and innovative multimedia including interactive radio campaigns, comics, videos, posters/leaflets, and SMS messages. By 2017, a total of 553,800 farmers had been reached (47% female), 33% more than the already ambitious target for 2017 (Fig. 2).
The project and its partners in 2017 established 1,454 demonstrations and 25,071 adaptation trials across the target countries. Most households (49%) were reached through demonstrations followed by field days and agricultural shows (27%). Through the end-ofseason evaluation feedback sessions, about 90 farmer groups across Ghana, Kenya, and Uganda, evaluated the different approaches whereas 76 groups evaluated adaptations in Ghana and Uganda.
Farmers indicated their preference for demonstrations as they gave an opportunity for them to “see, learn, and do,” when organized together. Demonstrations are also familiar platforms for farmers and make it easier to engage in and fit in with existing partner systems.
Field days also offer a platform to link with other value chain actors such as agrodealers and produce buyers, create linkages to access inputs and output markets, and offer broader learning as other farmers participate. Farmers indicated the unique opportunity given to individuals to practice the use of the technologies outside the group and to change it as desired.
Although participation and preferences varied for each approach, awareness and knowledge levels about the technologies increased among farmers and resulted in the use of the technologies. A total of 182 farmers in Uganda participated in demonstrations only and 124 (68%) used the introduced varieties (Maksoy 3N); 54% of farmers who participated in the evaluations used at least a single technology with most using introduced varieties, spacing, fertilizers, and inoculants.
The data presented is from the project’s Monitoring Evaluation and Learning (MEL) system. Other evaluations on the (cost)-effectiveness of the different dissemination approaches were conducted by an MSc student comparing radio to demonstration plots. The findings showed that farmers learn more from demonstrations compared to radio but net costs and learning increase favor radio campaigns in cost effectiveness. This led to N2Africa’s sister project, Gender and the Legume Alliance: Integrating multimedia communication approaches and input brokerage (GALA) on farmer learning and change in behavior following radio and SMS campaigns. Seventy percent of farmers declared they had changed their behavior; radio with SMS was most effective followed by SMS, and radio alone.
Sustainable input supply
To address the challenge of limited access to and use of legume seeds, inoculants, and P-rich fertilizers, the countries continued to pursue the various strategies put in place in 2016. To sustain the production of certified seed, national seed systems were supported (e.g., ARI Uyole, Tanzania) to produce foundation seed for seed companies to produce certified seed. Others have linked seed companies and other partners directly to institutions that produce foundation seed, e.g., The Inventive Minds and EGALF Ventures in Nigeria have been linked to the University of Agriculture in Makurdi where they access foundation seed for their community seed producers. A total of 48 tons of foundation seed was produced and/or accessed across the selected countries.
To ensure legume seed is available at community level, the project continued to promote over 4,000 farmers to produce certified or quality declared seed across the countries. In aligning marketing seed with grassroot producer groups, 1,590 tons of seed were sold by seed companies, agrodealers, and community seed producers, increasing the cumulative volume of seeds used by farmers to 3,399 from 1,809 tons in 2016, achieving 74% of the target for 2017.
Table 2 shows that supported farmer groups had access to and used 67% of seed demanded across the various legumes. Some farmer groups indicated their interest and the volume required but did not purchase for various reasons including limited access to agrodealers and climatic changes. Some varieties are not resistant to drought and there was poor market access for those varieties.
In 2017, the volume of inoculants and fertilizers used by farmers increased compared to 2016 (Figs. 3 and 4). About 79% of the volume of inoculant and 65% of the volume of fertilizer were achieved in relation to targets of 39 t/year and 7,700 t/year. Several strategies implemented together with partners contributed to this success. Agro-inputs Suppliers Ltd (AISL) in Malawi, for instance, invested in the distribution chain by procuring 15 solar-driven coolers for proper Nitrofix inoculant storage in 15 of its outlets and has constructed a permanent and fully equipped laboratory for inoculant production.
Although the overall targets for 2017 have not been met, the strategies implemented in 2017 will continue to yield results as the private sector continues to invest. For example, in Ghana, dissemination activities with YARA resulted in an increase in P-fertilizer used by farmers (e.g., from 150 t in 2016 to 194.6 t in 2017) excluding quantities distributed through the Government of Ghana’s Planting for Food and Jobs program and this partnership is envisaged to continue in 2018. In Nigeria, the ABP program contributed to 78% sales of inoculants in 2017.
To sustain accessibility to improved seeds, countries have put in place various strategies including seed companies contracting trained seed producers as outgrowers. Other countries have also linked seed producers to seed companies for mopping up seeds produced. In addition, many more agrodealers (136) were engaged and linked to various farmer groups. About 32% stocked more than one legume input 68% stocked seeds, 32% stocked fertilizer, and 28% stocked inoculants. Most inoculants were distributed in Ethiopia through cooperative unions in addition to two agrodealers.
Over 900 farmer groups were able to estimate inputs, especially seeds, needed for each season. However, this needs further support to ensure timely compilation and delivery to the inputdealers and access to input price information by farmers. Assessment of these systems has been made and an ICT-based demand quantification system is being piloted in Ethiopia, Ghana, Nigeria, and Uganda. Tanzania, however, has adopted the Village Based Agricultural Advisors (VBAA) and Community Volunteers (CV) models for input demand quantification for the upcoming year. The latter was based on limitations in the previous system where farmer groups quantified their demands but lacked price information.
Output market access and collective marketing
In total, 149,818 persons (46% female) were involved in collective marketing and value addition. The scales of operation were at both household and commercial levels. Table 3 is the aggregated data from countries and crops and indicates that 77% of the 2017 target has been achieved for participation in collective marketing.
Due to high demand for the produce, the price margin between collective marketing and individual selling is minimal in, for instance, Borno State. Most farmers among groups therefore sold individually without participating in the collective sales.
Farmers across the countries, at times, complained of delayed payments when they had collectively sold to major buyers, limited access to market information in comparing prevailing market prices to those being offered, and high storage costs for bulking.
In Tanzania, the introduction of VAT on animal feed increased prices and reduced demand. Animal feed processors could therefore not process soybean purchased in 2016. This decision has been reversed and hope fully the demand for soybean will revert in 2018.