Microdosing – a key proven technology for sub-Saharan Africa
The story launched as a timeline
ICRISAT’s first interactive timeline is launched this week showing the story of fertilizer microdosing in Africa. ICRISAT scientists developed the microdosing technique and this story covers the wide variety of initiatives and organizations who further tested and implemented the technology across Africa.
Small doses of fertilizer applied in the right place at the right time, combined with an inventory credit system (warrantage) introduced by the FAO supported Intrants project, lead to large benefits in yields and incomes in several countries in sub-Saharan Africa.
What is microdosing?
Microdosing is the strategic application of small quantities of fertilizers (three-finger pinch or full bottle cap) in the planting hole or to the base of the plants shortly after planting (10 to 14 days). With the efficient use of fertilizer, the roots grow out more quickly, helping the plant capture more native (non-added) nutrients before the rains leach them down below the root zone.
Warrantage system
The ‘warrantage’ or inventory credit approach is where farmers place part of their harvest in a local storehouse in return for inventory credit. This allows them to meet pressing post-harvest expenses and engage in dry season income generating activities, such as sheep fattening, vegetable cultivation using small-scale (drip) irrigation, groundnut oil extraction and small trading. The stored grain may be sold later in the year at a much higher price, ensuring farmers make a good profit.
Moreover, this cooperative approach trains farmers to work together to protect stored grains from insects and also helps them to buy fertilizer in bulk and repackage it in smaller, more affordable units through local input stores. Hundreds of farmer organizations in the region now use the warrantage system, which links them directly not only to markets but also to financial institutions.
Impacts
In West Africa, some 25,000 smallholder farmers in Mali, Burkina Faso and Niger have learned the technique and experienced increases in sorghum and millet yields of 44 to 120%, along with an increase in their family incomes of
50 to 130%.
In Zimbabwe, despite poorer than average rains, microdosing increased grain yields, enabling about 170,000 households to increase cereal production by an estimated 40,000 tons. The program significantly improved household food security and saved US$7 million in food imports, generated a net present value of US$26 million and an internal rate of return of 36% by 2013. Now 300,000 farmers are practicing this technique in Zimbabwe. Many of these farmers became interested in investing their own resources in fertilizer, but access has remained a constraint. The program has started working with fertilizer companies to test strategies for resolving this problem, through improved access to affordable smaller packs of fertilizer.
Need for microdosing
Land degradation affects more than half of Africa, leading to estimated losses of US$42 billion in income and 5 million hectares of productive land each year. Crop yields are low as a result of poor farming techniques, soils suffer from nutrient deficiency and lack of water, particularly in sub-Saharan Africa. Farmers are unable to invest in fertilizer, triggering a cycle of soil nutrient depletion, low productivity and hunger.
Unable to feed their families, farmers abandon unproductive land to clear forests and plow new areas. Clearing new lands for farming accounts for an estimated 70% of the deforestation in sub-Saharan Africa.
Microdosing technique uses only about one-tenth of the amount of fertilizer typically used on wheat, and one-twentieth of that used on maize in the USA. Yet in sub-Saharan Africa, crops are so starved of nutrients such as phosphorous, potassium and nitrogen that even this micro amount often doubles crop yields.
The future
Although results have shown consistent yield increases, farmers have reported that microdosing is time consuming and laborious and that it is difficult to ensure each plant gets the right dose of fertilizer. In an attempt to address these issues, researchers are looking at packaging the correct dose of fertilizer as a tablet that aids application, and this is proving to be popular. In collaboration with partners in national agricultural research systems, ICRISAT is also exploring the use of seed coating and an animal-drawn mechanized planter as other options to further reduce the quantity of fertilizer used, as well as to address the labor constraint.
Lack of access to fertilizer and credit, insufficient flows of information, inadequate training for farmers and inappropriate policies have been identified as major constraints to the widespread adoption of the technology in sub-Saharan Africa. Greater adoption of microdosing requires supportive and complementary institutional innovations, as well as input and output market linkages.
View the interactive timeline at: https://icrisat.org/Timelines/microdosing/