PROFESSIONAL’S COLUMN
John Wendt: Balanced Nutrition Research at IFDC
In most countries in sub-Saharan Africa, only
fertilizers containing nitrogen, phosphorus
and potassium (N, P and K) are available
to smallholder farmers. However, yield
increases due to these fertilizers are often
modest. In 2012, IFDC’s projects in east
and southern Africa initiated complete soil
analyses in their regions of operation. Results
from all countries – Rwanda, Burundi, Uganda,
Zambia and Mozambique – show wide-scale
deficiencies of multiple SMNs to be the norm
rather than the exception. The entire country
of Ethiopia was similarly mapped, supported
by Ethiopia’s Agricultural Transformation
Agency.
Photo: John Wendt,
IFDC senior expert
in soil fertility
management (right),
discusses IFDC
projects with Rob
Groot, director of
Donor Relations.
Consequent field trials designed to
identify response to different nutrients show that the secondary nutrients sulfur, calcium and
magnesium and the micronutrients zinc, boron and copper are the most common nutrient
deficiencies. Yield responses in general are on the order of 20 to 50 percent. The research
also shows that in order to realize optimal response, all deficient nutrients must be addressed
in combination. Failure to include any one deficient nutrient can severely limit the response to
others. Supplying all deficient nutrients in combination is the “balanced nutrition” approach.
IFDC has collaborated with national agricultural research and extension services to evaluate
balanced nutrition on a number of crops. The entire countries of Rwanda and Burundi have
been mapped on a macro scale for all nutrient deficiencies through the CATALIST-2 and
PAN-PNSEB projects. Response trials in these countries show that yields of rice, beans, maize,
potato and wheat are dramatically increased. It is now national priority in both countries to
make balanced fertilizers available to smallholder farmers, and to support these fertilizers with
subsidies previously reserved for NPK fertilizers.
“[T]o realize optimal
response, all deficient
nutrients must be
addressed in combination.”
To achieve
this, IFDC has
engaged regional
fertilizer suppliers
and blenders. A
balanced nutrition
workshop in
Johannesburg,
South Africa, was
conducted in
October 2014.
The 60 attendees represented fertilizer blenders, representatives of national agricultural
research institutions, policymakers and fertilizer suppliers. A similar workshop will take place
in Abidjan, Côte d’Ivoire, in April 2015. Large-scale demonstrations of balanced fertilizers are
underway in Rwanda and Burundi to further validate response and create farmer demand.
Balanced blends provided by regional blenders are also being evaluated in Mozambique and
Zambia. Research continues to find optimal ways of delivering SMNs. Added nutrients result in
added costs to farmers, so it is important to keep these costs as low as possible. Micronutrient
fertilizer coatings, foliar products and very low rates of dolomite (to supply calcium and
magnesium) all show promise.
Our ultimate objective is to make balanced fertilizers available to all African smallholder
farmers to dramatically increase yields, food security and return on fertilizer investments.
The balanced nutrition initiative will require careful documentation of successes and a wellconsidered strategy to realize its potential.
IFDC Magazine
23