Senior Program Officer, Soil Health and Lead, Digital Farmer Services, Bill & Melinda Gates Foundation
How does plant nutrition fit into the Agricultural Development focus of the Bill and Melinda Gates Foundation?
There is abundant evidence that in Sub-Saharan Africa and many parts of South Asia where we focus our agriculture investments, depleted soils are common. Crop productivity in these regions cannot be increased without a greater emphasis on Integrated Soil Fertility Management (ISFM) practices that substantially and sustainably improve soil nutrients. We thus endorse the principles of ISFM, which includes strategic applications of properly formulated fertilizer blends, use of organic inputs such as livestock manure, field preparation to improve water retention and safeguard against runoff and access to improved crop varieties. And all of these elements must be pursued with technical guidance on how best to combine them within the context of local conditions.
The overall aim is to optimize the efficiency of applied nutrients in ways that maintain long-term soil health and achieve sustainable increases in crop productivity. Where feasible, we seek to improve soil health by encouraging farmers to grow legumes—sometimes mixed in with cereal crops like maize—to take advantage of their capacity to draw nitrogen from the air into the soil. In addition to livestock manure, organic resources can include crop residues and both can be combined with judicious applications of mineral fertilizers to address soil nutrient deficiencies. Of course, all inputs are to be managed following sound agronomic and economic principles aimed at sustainable intensification.
How can smallholders gain improved access to fertilizers?
It’s important to understand the context for fertilizer consumption in places like sub-Saharan Africa, where farmers in general apply a small fraction of the amount used in other parts of the world, mainly due to access issues. While it is critical to avoid the overuse of fertilizers, the key challenge for most smallholder farmers in sub-Saharan Africa is their lack of access to sufficient amounts of fertilizers, mineral or organic. There are also issues related to uneven fertilizer quality and the lack of blends that are aligned to local soil conditions, along with the need for technical knowledge about how to make the most of available fertilizers through good agronomic practices such as plant spacing or fertilizer placement.
Smallholder farmers typically purchase fertilizer and other inputs from local agro-dealer shops. Support for these small, local businesses is needed in the form of training and finance, along with links to supply chains that can provide a steady flow of affordable, quality product. Access to inputs has improved in recent years in sub-Saharan Africa, but is still insufficient. There are opportunities for improvements, such as through a “bundling” approach in which fertilizers are made available as part of a package of products and services that include certified, high-yield seeds, technical advice, insurance and market linkages.
What does the ideal fertilizer look like?
An ideal fertilizer is tailored to the nutrient needs of a specific crop type and adapted to the composition of local soils. Nutrient gaps in local soils can limit the yields of even the best seeds and are a major barrier to achieving sustainable increases in farm productivity. While there are significant opportunities for increasing the crop response to inorganic fertilizer (e.g., through the development of soil- and crop-specific fertilizer formulas), they need to be guided by insights into the economic return on fertilizer investments. It’s also important to consider situations where fertilizer is not an option and how farmers can get the most from available assets. While not an ideal situation, embracing the principles of integrated soil fertility management can substantially improve soil health even in the absence of fertilizers.
How can a multi stakeholder forum such as this one help to identify further research priorities into plant nutrition, or more effectively bring research findings into the field?
We need to discuss the role of plant nutrition in the broader context of soil health and agronomy. A functioning research system is a key agricultural enabler playing a translational role of converting agricultural data into actionable knowledge and insights, as well as creating and validating new research through contextual evidence. This applies across the agriculture value chain, providing expert knowledge via applied research and field trials on soils, crops, irrigation, agricultural inputs and other agronomic fundamentals to assist in optimizing each step of crop production.
Soil health and agronomy research deserves greater attention at this opportune moment when digital innovation has led to the development of new soil diagnostic tools and cost-effective approaches for conducting agronomic research at scale. We also see innovative and promising approaches for reaching farmers with adapted inputs and innovative services at scale even in challenging environments. It will take new, lean partnerships to better translate the global public goods developed by agricultural research into more productive, sustainable farms. The stresses on food production caused by climate change greatly increases the urgency to develop and implement new solutions.