Addressing malnutrition with biofortified maize in Zimbabwe: from crop management to policy and consumers

Lead Research Organisation: Rothamsted Research
Department Name: Sustainable Agriculture Sciences-H


The double burden of malnutrition refers to the suboptimal intake of essential nutrients (minerals, metals and vitamins), either caused simply by inadequate dietary intake and/or due to the intake of "empty calories" i.e., food that has sufficient calories but lacks adequate amounts of essential nutrients. This double burden falls disproportionally heavy on developing countries, and there on women and children. It directly increases child mortality and childhood stunting, and reduces people's ability mending diseases. In Zimbabwe, an estimated one in four children have vitamin A deficiency, two-thirds are living with iron deficiency and one in three have iron deficiency anaemia (UNICEF, 2019). And a quarter of children (0.76 million) under five in Zimbabwe are currently stunted. Among women of reproductive age, one in four have vitamin A deficiency, six in ten women have iron deficiency and one in four are anaemic.

Malnutrition and its negative effects are particularly common in rural areas where people mostly live from their own crop production and the diet is mostly cereal based. This group is difficult to reach with supplements and has basically no access to fortified processed food. As an alternative method, plant breeders developed "biofortified" crops, meaning crops with a higher content of minerals, metals and (pro)vitamin A (PVA). However, recent research has shown that the effectiveness of such biofortified crops is a) affected considerably by soil characteristics, and that b) their nutrient content can be enhanced with micronutrient fertilizer and other crop management options. To enable making best use of the new biofortified crop varieties we propose the following research:

Work package (WP) 1: what are the effects of agronomic management options on PVA concentration and micronutrient uptake of novel, biofortified maize lines. African soils are often poor and have a low fertility, resulting in low yields and low grain quality. This can, for example, be addressed with soil conservation methods (increased return of crop residues and reduced tillage), with macro and micro nutrient treatments, or with liming. However, little is known how such treatments affect the nutrient content in the newly developed biofortified maize varieties. We will, therefore, test a range of the new varieties under several agronomic management options, to identify the best conditions and treatments for high quality, nutritious maize.

WP2. Testing the effectiveness of agronomic biofortification at the farm-scale. As mentioned above, African soils are often poor, but they are also very variable. Farmers of course know their soils well, they know where the crops grow well and where not, and they often increase soil fertility in particular fields (where they dump kitchen refuse or crop residues, where the cattle are kept at night, etc). Therefore, farmers could grow biofortified crops in preferential places but it is unknown how much this could contribute to an improved nutritional value. We will test these options with 60 farmers for two seasons for their effectiveness, feasibility, and possible impact.

WP3. Closing the nutrient gap or Predicting the effect of bio + agro fortification at the national level. Although maize is a very important staple for most people in Zimbabwe, they also eat other food. And only their total "food basket" determines their nutrient uptake. Knowledge of the food basket composition and of the nutrient content of all items in the basket allows then to estimate the possible contribution of the bio-and agro-fortified food on the nutrition of the people. WP3 will estimate this impact for all regions in Zimbabwe based on WP1 and WP2 results in combination with national statistics on food consumption and, where necessary, some additional analysis of common food items.

WP4. This WP focuses on upscaling and dissemination and has no research components.

Planned Impact

The direct impact of our research is aimed towards enhancing the quality of life, health and well-being of people in sub-Saharan Africa (SSA). The initial focus of the project is Zimbabwe (Low Income Country on the DAC List of ODA Recipients), which has considerable micronutrient deficiency (MND) problems, but results will be is easily scalable to neighbouring countries in East Africa with a similar dependence on maize as main stable and equally wide spread micronutrient deficiencies. By developing a multidisciplinary approach combining biofortification and agronomic fortification with a dissemination and policy framework, the project will address several of the UN Sustainable Development Goals (SDGs), including the elimination of hunger (SDG2), good health and wellbeing (SDG3) and responsible consumption and production (SDG12).

Finalized and ongoing "GeoNutrition" projects in Malawi and Ethiopia are already improving our understanding of the link between soil characteristics and crop composition for Zn and Se. Our ongoing GeoNutrition project also tests micro-nutrient fertilizer treatments for maize in Ethiopia. Another project led by Rothamsted Research, the "Africa Soils Information Service (AfSIS)" has prepared digital soil maps which can be used to localize micronutrient deficiencies at a regional scale across Africa. On the other hand, CIMMYT developed provitamin A maize germplasm and released it already in Malawi, Tanzania, Zambia and Zimbabwe. Efficacy studies demonstrated that increasing provitamin A intake through consuming provitamin A maize has a positive effect on the vitamin A status of consumers. Our project brings together these different efforts to combine biofortified maize with agronomic fortification and knowledge of farmers' crop management to maximize the benefit for the health of all consumers.
The idea of combining these different approaches to maximize the nutritional quality of maize seems obvious but limited research has been conducted and is, therefore, highly innovative (partly because not many biofortified crop varieties have been released). The proposed analysis of grain quality of biofortified lines on farmers' fields with a range of soil quality levels is also novel and will allow a much better evaluation of the possible impact of the bio/agronomic fortification approach in the real environment of smallholder farmers.

From a natural sciences perspective, the data and approaches proposed in our project have the potential to shape/enhance soil and crop management decisions, and investment in breeding programmes. For example, it can inform decisions on how to prioritise R&D and deploy new traits/varieties most effectively to benefit consumers, farmers, and the wider industry. We also believe that the geospatial food basket analysis together with our results on grain quality will identify hotspots of micronutrient deficiency and enable more targeted interventions for bio/agronomic fortification. It could also provide considerable value for monitoring/testing policy interventions through a geospatial framework.

From a social sciences perspective, food systems research from both consumer (demand-driven) and producer (supply driven) perspectives could potentially be transformed by being able to account for spatial variations in food mineral compositions. The flows of some minerals (e.g. zinc, iron) through food systems can be integrated into health burden/outcome-based socioeconomic frameworks (e.g. using Disability Adjusted Life Years, DALYs). Thus, our findings can contribute immediately towards influencing public policies to address micronutrient deficiencies at local, regional and national scales, e.g. through education and dietary diversification. Our "Pathways to Impact" activities will align directly with ongoing activities of the Food and Nutrition Council, and therefore be integrated into national efforts to combat the double burden of malnutrition.


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Description The results of the baseline survey highlight low food security - households reported having adequate food supply in average for 6.17 months per year - and low dietary diversity - the average household dietary score (24 h recall, 12 food groups) was 4.13. Only 25.2% of households declared having consumed animal-based vitamin A-rich food in the last 24 hours, but plant-based vitamin A-rich food was consumed by 75.2% of the households. This is mainly due to the high consumption of dark-green leafy vegetables (consumed by 65.7% of households in the 24 hours proceeding the interview). More detailed analyses will be conducted early 2021 to assess the potential contribution of PVA maize to vitamin A uptake. We will also analyse the dark-green leafy vegetables for its vitamin A content. Only 11.1% of the farms interviewed new about PVA maize and only 8.8% had experience growing PVA maize. The survey indicated also that there was a gender-dependent preference in maize varieties, where women preferred shorter duration varieties, possibly for reduced risk of crop failure and/or to close the hunger gap before harvest. However, this result still needs to be validated.
Exploitation Route This output can actually influence the development (maize breeders) and targeting (seed distributors) of maize varieties.
Sectors Agriculture, Food and Drink

Description The project is only in its first year and field experiments in the first season are still ongoing. The overarching goal of this proposal is to reduce the double burden of malnutrition in Zimbabwe with a combination of biofortified maize varieties and adjusted crop management options. We believe that an integrated agriculture intervention is the best way to fill the remaining nutrient gaps for young children and women at risk of stunting and anaemia. Providing more nutritious crops is an important way to empower especially rural populations to improve their diet and health. Knowledge of the effect of crop management practices and soil characteristics on the nutritional quality maize will enable farmers, and especially women farmers, to make their own choices on how to improve their family health. Accompanying analyses of geospatial micronutrient deficiency risk areas and of regional food baskets will enable to improve the current spatial picture of malnutrition risk and ways to address it. We started to embed social science, gender and economic evaluations to assess how the interventions impact households, genders, market access and food security. We also initiated to accompany the technical elements of the project with stakeholder interaction, policy involvement and the development of dissemination materials and activities.
First Year Of Impact 2020
Sector Agriculture, Food and Drink
Impact Types Cultural,Policy & public services

Description Sensitizing the Government of Zimbabwe to the potential of agronomic and biofortification combined - project was presented to Dr John Basera, Permanent Secretary to the Minister of Lands, Agric, Fisheries, Water and Rural Resettlement
Geographic Reach National 
Policy Influence Type Gave evidence to a government review
Impact Impact not know yet, but knowledge of the combined use of biofortification and agricultural management options is essential to make the best use of these new technologies.
Title Baseline survey (306 farms) using KoBoToolbox 
Description We have developed a workflow on R to delineate typologies based on multidimentional scaling 
Type Of Material Data analysis technique 
Year Produced 2020 
Provided To Others? No  
Impact Significantly improve the classic statistical typology method (based on PCA and hierarchical clustering), by allowing factorial variables (e.g., gender, education) to be considered in addition to continuous variables. The typology was used as strata to select a stratified sample of farms where trials where established. 
Description Collaboration with Innovative Solutions for Agriculture Africa (iSDA Africa) 
Organisation Innovative Solutions for Decision Agriculture Ltd.
Country United Kingdom 
Sector Private 
PI Contribution We collaborated with iSDA to develop a new high-resolution soil map for Africa, which is now available online ( We also contributed to a related publication entitled "African Soil Properties and Nutrients Mapped at 30-m Spatial Resolution using Two-scale Ensemble Machine Learning" which was accepted for publication in the Nature Scientific Reports journal.
Collaborator Contribution The main contribution for this came from Rothamsted Research.
Impact The new high-resolution soil map for Africa is available online ( We also contributed to a related publication entitled "African Soil Properties and Nutrients Mapped at 30-m Spatial Resolution using Two-scale Ensemble Machine Learning" which was accepted for publication in the Nature Scientific Reports journal (soon to be available online).
Start Year 2020
Description Discussions with the Food and Nutrition Council (FNC) in Zimbabwe 
Organisation Food and Nutrition Council
Country Zimbabwe 
Sector Public 
PI Contribution The Food and Nutrition Council (FNC) is the lead agency to coordinate, analyse and promote a cohesive national response by multiple sectors and stakeholders to food and nutrition insecurity in Zimbabwe. The FNC is also the Zimbabwe Scaling Up Nutrition (SUN) national convener. The FNC acts as a Programmatic Support Agency for food and nutrition stakeholders. The project had repeated online meetings with the FNC to discuss our collaboration and how our project could distribute project findings to stakeholders in the country.
Collaborator Contribution Our project partner, CIMMYT, established the contact and organize joint meetings.
Impact Advanced planning for the participation of project scientists in stakeholder meetings.
Start Year 2020