On-farm storage loss estimates of maize in Kenya using community survey methods.

Maize is the most important staple in sub-Saharan Africa (SSA), with highly seasonal production. High storage losses affect food security, but good estimations are lacking. A new method using focus group discussions (FGDs) was tested with 121 communities (1439 farmers, 52% women) in Kenya's six maize-growing zones, to estimate the maize losses to storage pests and analyze farmer practices. As control strategies, half of the farmers used chemical pesticides (49%), while hermetic bags (16%) and botanicals (15%) were also popular. Relative loss from weevils in the long rains was estimated at 23%, in the short rains 18%, and annually 21%. Fewer farmers were affected by the larger grain borer (LGB) than by maize weevils: 42% in the long rainy season and 32% in the short rainy season; losses from LGB were also smaller: 19% in the long season, 17% in the short season, and 18% over the year. Total storage loss, from both species combined, was estimated at 36%, or 671,000 tonnes per year. The greatest losses occur in the humid areas, especially the moist mid-altitudes (56%), and with smaller loss in the drylands (20-23%). Extrapolating the point data and overlaying with the maize production map shows the geographic distribution of the losses, with the most important area found around Lake Victoria. FGDs provide convenient and cheap tools to estimate storage losses in representative communities, but a total loss estimate of 36% is higher than is found in other studies, so its accuracy and framing effects need to be assessed. We conclude that storage pests remain a major problem, especially in western Kenya, and that the use of environmentally friendly technologies such as hermetic storage and botanicals needs more attention, both by the public extension service and private agrodealers.

Caregivers Systematically Overestimate Their Child's Height-for-Age Relative to Other Children in Rural Ethiopia.

BACKGROUND: Stunting affects one-quarter of children <5 y of age, yet little is known about the accuracy of caregivers' perceptions regarding their child's linear growth. Most existing quantitative research on this topic has been conducted in high-income countries and has examined perceptions of children's weight rather than height. OBJECTIVES: In rural Ethiopia where linear growth faltering is highly prevalent, this study aimed to better understand how caregivers perceive their child's growth. The objectives of this analysis were to 1) assess caregivers' perceptions of their child's height; 2) investigate whether there is a discrepancy between a child's actual height and caregivers' perceptions of their child's height; and 3) examine the factors that influence discrepancies in estimating a child's height (secondary outcomes), including the role of the average height in the community (primary outcome). METHODS: We conducted a cross-sectional analysis using data from 808 woman caregivers of children ages 6-35 mo in the Oromia region of Ethiopia. We assessed caregivers' rankings (from 1 to 10) of their child's height relative to other children their age in their village. We then converted these rankings to z scores based on an age- and region-specific distribution in order to calculate their difference with the child's actual height-for-age z score and to determine the degree of overestimation. Lastly, we used multivariate log Poisson regressions to determine factors associated with overestimating a child's height. RESULTS: Forty-three percent of caregivers scored their child's height as the median; 37% overestimated their child's height relative to other children. Regression results showed caregivers who were poorer, and had children who were female, older, and stunted, were more likely to overestimate. CONCLUSIONS: Our findings suggest that caregivers of young children in Oromia systematically overestimated their children's height, which could adversely affect child health if these misperceptions translate to insufficient care-seeking behavior or feeding choices for children.

Exposure to aflatoxins and fumonisins and linear growth of children in rural Ethiopia: a longitudinal study.

OBJECTIVE: We hypothesise that exposure to aflatoxins and fumonisins, measured in serum, alters protein synthesis, reducing serum protein and insulin-like growth factor 1 (IGF-1), increasing inflammation and infection, leading to child's linear growth failure. DESIGN: Children 6-35 months, stratified by baseline stunting, were subsampled from an intervention trial on quality protein maize consumption and evaluated at two time-points. SETTING: Blood samples and anthropometric data were collected in the pre-harvest (August-September 2015) and post-harvest (February 2016) seasons in rural Ethiopia. PARTICIPANTS: 102 children (50 stunted and 52 non-stunted). RESULTS: Proportions of children exposed to aflatoxin G1, aflatoxin G2 and aflatoxin M1 were higher in the pre-harvest (8, 33 and 7, respectively) compared to post-harvest season (4, 28 and 4, respectively). The proportion of children exposed to any aflatoxin was higher in the pre-harvest than post-harvest season (51 % v. 41 %). Fumonisin exposure ranged from 0 % to 11 %. In joint statistical tests, aflatoxin exposure was associated with serum biomarkers of inflammation (C-reactive protein, α-1-glycoprotein) and protein status (transthyretin, lysine, tryptophan), IGF-1 and linear growth (all P < 0·01). However, exposure to specific aflatoxins was not significantly associated with any biomarkers or outcomes (all P > 0·05). CONCLUSIONS: Aflatoxin exposure among rural Ethiopian children was high, with large variation between seasons and individual aflatoxins. Fumonisin exposure was low. There was no clear association between aflatoxin exposure and protein status, inflammation or linear growth. A larger study may be needed to examine the potential biological interactions, and the assessment of aflatoxins in food is needed to determine sources of high exposure.

Using Panel Community Surveys to Track the Impact of Crop Pests Over Time and Space - The Case of Maize Lethal Necrosis (MLN) Disease in Kenya from 2013 to 2018.

Maize lethal necrosis (MLN) disease appeared in Kenya in 2011, causing major damage. In a first survey of 121 communities in 2013, participants estimated the proportion of households affected and the yield loss in affected areas; from this survey, the overall loss was estimated at 22%, concentrated in western Kenya (94%). Efforts to combat the disease included planting resistant varieties, creating awareness of MLN management, and producing pathogen-free seed. In 2018, the same communities were revisited and asked the same questions, establishing a panel community survey. The results showed that incidents of MLN had greatly decreased, and the number of communities that had observed it had reduced from 76% in 2013 to 26% by the long rains of 2018; while still common in western Kenya (60%), MLN had greatly reduced elsewhere (to 10%). In 2013, 40% of farmers were affected, yield loss among affected farmers was estimated at 44%, and total yield loss was estimated at 22% (a production loss of 0.5 million metric tons/year), valued at US$187 million. By the long rains of 2018, 23% of farmers were affected, with a loss among affected farmers of 36%; overall annual loss was estimated at 8.5% or 0.37 million metric tons, valued at US$109 million, concentrated in western Kenya (79%). Of the recommended control measures, only the removal of diseased plants was commonly used (by 62% of affected communities), but not the use of agronomic practices (11%) or resistant varieties (9.5%). The reasons for the reduction in MLN are not well understood; external factors such as spraying insecticide against fall armyworm and unfavorable weather likely played a role, as did using disease-free seed, but not the use of resistant varieties or appropriate management practices. Still, as the pathogen remains in the fields, it is important to keep disseminating these control methods, particularly resistant varieties.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.

Spread and impact of fall armyworm (Spodoptera frugiperda J.E. Smith) in maize production areas of Kenya.

Fall armyworm (FAW), one of the most important pests of maize in Latin America, suddenly appeared in Africa in 2016 and spread rapidly. Estimates of crop losses due to FAW are essential in order to compare the impact of these losses with the cost of controlling FAW and advise appropriate technology dissemination and policy. In this study, therefore, crop losses due to FAW in 2017 and 2018 were estimated in all the maize production areas of Kenya. Data were collected during June and July 2018 through 121 group discussions with 1439 farmers, separately with men (697) and women (742), in communities that were randomly selected to represent the major maize growing areas. The results showed that most participants (82%) could correctly identify the FAW from pictures. By 2016, FAW was observed by more than half of the communities (53%), with most of the other half first observing FAW in 2017. The proportion of farmers affected by FAW substantially increased, from the long rains of 2017 (63%) to the long rains of 2018 (83%), and in all zones except for the high tropics and moist mid-altitudes. However, the percentage of loss experienced by affected farmers decreased slightly, from 54% in 2017 to 42% in 2018. In 2017, the low- and medium-potential maize-production areas were the most affected, with losses of >50%, with high-potential areas facing losses of about 30%, resulting in a total loss of 37% for the whole country. In the main 2018 season, losses in the low- and medium-potential areas were less - about 20%, but the high-potential areas were now more affected, leading to a total estimate of 33%. We conclude that FAW has suddenly become a major pest in Kenya, causing losses of about a third of the annual maize production, estimated at about 1 million tonnes.

On-farm performance and farmers' participatory assessment of new stress-tolerant maize hybrids in Eastern Africa.

The development and deployment of high-yielding stress tolerant maize hybrids are important components of the efforts to increase maize productivity in eastern Africa. This study was conducted to: i) evaluate selected, stress-tolerant maize hybrids under farmers' conditions; ii) identify farmers' selection criteria in selecting maize hybrids; and iii) have farmers evaluate the new varieties according to those criteria. Two sets of trials, one with 12 early-to-intermediate maturing and the other with 13 intermediate-to-late maturing hybrids, improved for tolerance to multiple stresses common in farmers' fields in eastern Africa (drought, northern corn leaf blight, gray leaf spot, common rust, maize streak virus), were evaluated on-farm under smallholder farmers' conditions in a total of 42 and 40 environments (site-year-management combinations), respectively, across Kenya, Uganda, Tanzania and Rwanda in 2016 and 2017. Farmer-participatory variety evaluation was conducted at 27 sites in Kenya and Rwanda, with a total of 2025 participating farmers. Differential performance of the hybrids was observed under low-yielding (<3 t ha-1) and high-yielding (>3 t ha-1) environments. The new stress-tolerant maize hybrids had a much better grain-yield performance than the best commercial checks under smallholder farmer growing environments but had a comparable grain-yield performance under optimal conditions. These hybrids also showed better grain-yield stability across the testing environments, providing an evidence for the success of the maize-breeding approach. In addition, the new stress- tolerant varieties outperformed the internal genetic checks, indicating genetic gain under farmers' conditions. Farmers gave high importance to grain yield in both farmer-stated preferences (through scores) and farmer-revealed preferences of criteria (revealed by regressing the overall scores on the scores for the individual criteria). The top-yielding hybrids in both maturity groups also received the farmers' highest overall scores. Farmers ranked yield, early maturity, cob size and number of cobs as the most important traits for variety preference. The criteria for the different hybrids did not differ between men and women farmers. Farmers gave priority to many different traits in addition to grain yield, but this may not be applicable across all maize-growing regions. Farmer-stated importance of the different criteria, however, were quite different from farmer- revealed importance. Further, there were significant differences between men and women in the revealed-importance of the criteria. We conclude that incorporating farmers' selection criteria in the stage-gate advancement process of new hybrids by the breeders is useful under the changing maize-growing environments in sub-Saharan Africa, and recommended to increase the turnover of new maize hybrids.

Measuring consumers' interest in instant fortified pearl millet products: a field experiment in Touba, Senegal.

BACKGROUND: In Africa, food-processing industries are emerging fast, especially for cereals. New low-cost extrusion cookers give small enterprises an opportunity to enter the market for processed cereal products, in particular instant, fortified and flavoured mixes. Before engaging in the marketing of these products, consumers' interest needs to be assessed. This study used a combination of affective tests and experimental auctions with 200 consumers in Touba, Senegal, to evaluate four new products with conventional pearl millet flour as the control: instant pearl millet flour, instant pearl millet flour with added dry mango and carrot powder (naturally fortified), and the previous products with added conventional chemical micronutrient fortificants. RESULTS: During affective tests, consumers made little distinction between the five products in appearance, aroma, taste and overall appreciation. The experimental auctions showed that, without providing additional information on the products, there was no difference in 'willingness to pay' (WTP) between them. However, after that information is provided, consumers were willing to pay a modest premium for instant flour, and a large premium for added mango and carrot extract and for added micronutrients, but were not willing to pay a premium if those micronutrients came from natural sources. Income increased overall WTP, while education increased WTP for instant flour. CONCLUSION: There is a potential market in low-income African countries for instant and fortified cereal food products, but likely in the higher income and education groups. The increased cost needs to be compared to the premiums consumers are willing to pay. In the next step, the new and promising products could be tested in pilot markets, with target consumers. © 2017 Society of Chemical Industry.

Women's and children's acceptance of biofortified quality protein maize for complementary feeding in rural Ethiopia.

BACKGROUND: For impact of nutritionally improved biofortified crops, consumer acceptance specifically by women and children is necessary when the target beneficiaries are young children. The objective was to assess women's and children's acceptance of a biofortified crop, quality protein maize (QPM), for complementary feeding in rural Ethiopia. RESULTS: Randomly sampled mothers (n = 61) of young children (6-24 months) evaluated flours from a QPM and a conventional maize variety for five sensory characteristics and overall acceptance by mother and child in a home use test with a double-blind, randomized controlled cross-over design. Women distinguished the varieties when used to prepare porridge, and QPM scored more favorably for texture in hand and mouth (both P < 0.05). The varieties did not differ in overall acceptance, which was, however, affected by order of presentation, mothers' number of children, and enumerators who collected data (all P < 0.05). Aroma and taste were key in mothers' acceptance, and appearance was further important for children. Women were more than twice as likely to prefer QPM over conventional maize. CONCLUSION: Consumer acceptance is unlikely to impede uptake and impact of QPM on young children's nutritional status. Home use testing proved feasible for assessing acceptance in rural areas with food insecurity and limited education. © 2015 Society of Chemical Industry.

Consumer acceptance of quality protein maize (QPM) in East Africa.

BACKGROUND: Undernutrition in sub-Saharan Africa remains problematic, and quality protein maize (QPM) can benefit populations whose diets are heavily based on maize and who are consequently at risk for inadequate intakes of quality protein. However, changes in the chemical composition of QPM may affect its sensory characteristics and, hence, acceptance. Acceptance tests were therefore conducted to evaluate QPM varieties in three East African countries using central location tests with one or two varieties in each country, using the most popular preparations: ugali (Tanzania), githeri (Kenya) and injera (Ethiopia). In total, 281 urban and rural consumers of both sexes and varying levels of education evaluated the products on standard sensory criteria: appearance, aroma, texture, taste and overall, using a Likert scale. RESULTS: The results show that African consumers can differentiate QPM products from their conventional counterparts, indicating that the QPM trait results in distinguishable sensory changes. Analysis by ordinal mixed regression models showed that consumers found QPM acceptable and even preferable to conventional maize. CONCLUSION: The sensory characteristics of QPM are therefore no impediment to its adoption; on the contrary, when coupled with good agronomic performance, they may help its utilization, leading to a positive impact in nutritionally vulnerable populations.

Varietal turn-over and their effect on yield and food security - Evidence from 20 years of household surveys in Kenya.

Agricultural technology is key to food security in SSA, but new maize varieties are not able to replace the old, trusted ones. This study uses data from four representative household surveys conducted in Kenya over 21 years, to show that younger maize varieties have a clear, although limited, effect on yield (4 kg/ha/year controlling for fertilizer) and food security. Unfortunately, this is not sufficient to entice farmers to adopt them, and adoption rates have barely increased despite the market liberalization that brought many private seed companies and their varieties in the market, as the parastatal Kenya Seed Company continues to dominate the market. As a result, in combination with low fertilizer use, yields have stagnated for the last three decennia.

Perspective article: Food security in tropical Africa through climate-smart plant health management.

Each year, Africa loses half of its harvest to pests (insects, pathogens, nematodes, weeds). To offset these losses and improve food security, pest management needs to be revamped urgently. Based on a synthesis of all 58 pest management projects conducted by IITA in its 55-year history, we advocate here for the implementation of the five following key climate-smart interventions, which have been shown to increase yields and decreasing CO2 outputs compared to the current practices that are largely based on the use of synthetic pesticides: 1. Sanitation at the country's borders and at the field level is the most cost-efficient way to prevent pest damage and losses from exotic pests entering new territories. 2. Good soil management strengthens the crop plant and enhances the effectiveness of all other interventions. 3. Biological control is the quickest and in the long run most cost-effective way to control invading insect pests and weeds. 4. Resistant varieties are often the only way to control already established diseases and are a mainstay control method in combination with other practices. 5. Various bio-pesticides based on viruses, bacteria and fungi against insects have been commercialized or can be produced on-farm; they are to replace synthetic pesticides, which continue to have large negative impacts on the environment and human health. To apply these five practices, new decision-support and climate services tools should be used to empower low-literacy farmers to take timely decisions about pest control and to act as business partners. Meanwhile, all actors in the pest control community should account for their environmental costs, which up to now are born solely by the community, while profits from pesticide sales are pocketed privately. To successfully disseminate these practices across the continent, enhanced and harmonized policy support is required.

Consumer preferences for maize products in urban Kenya.

BACKGROUND: New maize varieties have been biofortified with provitamin A, mainly a-carotene, which renders the grain yellow or orange. Unfortunately, many African consumers prefer white maize. The maize consumption patterns in Africa are, however, not known. OBJECTIVE: To determine which maize products African consumers prefer to purchase and which maize preparations they prefer to eat. METHODS: A survey of 600 consumers was conducted in Nairobi, Kenya, at three types of maize outlets: posho mills (small hammer mills), kiosks, and supermarkets. RESULTS: Clients of posho mills had lower incomes and less education than those of kiosks and supermarkets. The preferred maize product of the posho-mill clients was artisanal maize meal; the preferred product of the others was industrial maize meal. Maize is the preferred staple for lunch and dinner, eaten as a stiff porridge (ugali), followed by boiled maize and beans (githeri), regardless of socioeconomic background. For breakfast, only half the consumers prefer maize, mostly as a soft porridge (uji). This proportion is higher in low-income groups. Consumers show a strong preference for white maize over yellow, mostly for its organoleptic characteristics, and show less interest in biofortified maize. CONCLUSIONS: Maize is the major food staple in Nairobi, mostly eaten in a few distinct preparations. For biofortified yellow maize to be accepted, a strong public awareness campaign to inform consumers is needed, based on a sensory evaluation and the mass media, in particular on radio in the local language.

Economic analysis of pest problems in agriculture and food chains in Africa.

Economic impact of agricultural pests remains poorly studied, resulting in interventions rarely being evidence-based. When pests (re)emerge, researchers and donors often implement quick studies that tend to overestimate losses, leading to recommendations for immediate and substantial interventions. Incentives are lacking for scientists/research institutes to invest in objective pest assessments, as donors routinely fund projects without them. In this review, we argue for inclusion of social scientists and systematic economic analysis of pest problems and their control, consisting of four major steps: (1) estimating pests' extent and intensity, (2) conducting trials for technical and economical efficacy of control methods, (3) randomized controlled trials with participatory evaluation and effectiveness analysis of control options, and (4) impact assessment of pests and control methods. To optimize pest control, scientists and donors need to include socioeconomic analysis, leading to better use of research funds and reduction of negative environmental impacts.

A suite of agronomic factors can offset the effects of climate variability on rainfed maize production in Kenya.

Achieving food security in sub-Saharan Africa (SSA) is a multidimensional challenge. SSA reliance on food imports is expected to grow in the coming decades to meet the population's demand, projected to double to over 2 billion people by 2050. In addition, climate change is already affecting food production and supply chains across the region. Addressing these multiple food security challenges will necessitate rapid enhancements in agricultural productivity, which is influenced by a host of demographic, agronomic, and climatic factors. We use statistical approaches to examine rainfed maize in Kenya, where maize cultivation and consumption are widespread and central to livelihoods and national food security. We find that improving a suite of agronomic factors, such as applying fertilizer, planting certified seeds, and extension services, will have a greater effect on rainfed maize productivity than demographics and can offset the effects of climate change. These findings could also offer insights into similar challenges for other crops in Kenya and other SSA countries.

Incorporating male sterility increases hybrid maize yield in low input African farming systems.

Maize is a staple crop in sub-Saharan Africa, but yields remain sub-optimal. Improved breeding and seed systems are vital to increase productivity. We describe a hybrid seed production technology that will benefit seed companies and farmers. This technology improves efficiency and integrity of seed production by removing the need for detasseling. The resulting hybrids segregate 1:1 for pollen production, conserving resources for grain production and conferring a 200 kg ha-1 benefit across a range of yield levels. This represents a 10% increase for farmers operating at national average yield levels in sub-Saharan Africa. The yield benefit provided by fifty-percent non-pollen producing hybrids is the first example of a single gene technology in maize conferring a yield increase of this magnitude under low-input smallholder farmer conditions and across an array of hybrid backgrounds. Benefits to seed companies will provide incentives to improve smallholder farmer access to higher quality seed. Demonstrated farmer preference for these hybrids will help drive their adoption.

Zinc agronomic biofortification of staple crops may be a cost-effective strategy to alleviate zinc deficiency in Ethiopia.

Background: Inadequate dietary zinc (Zn) supplies and Zn deficiency (ZnD) are prevalent in Ethiopia, where cereals are major dietary sources, yet low in bioavailable Zn. Zinc agronomic biofortification (ZAB) of staple crops through application of Zn fertilizers may contribute to alleviating ZnD. However, large-scale promotion and adoption of ZAB requires evidence of the feasibility and public health benefits. This paper aimed to quantify the potential cost-effectiveness of ZAB of staple crops for alleviating ZnD in Ethiopia. Methods: Current burden of ZnD among children in Ethiopia was quantified using a disability-adjusted life years (DALYs) framework. Evidence on baseline dietary Zn intake, cereal consumption, and fertilizer response ratio was compiled from existing literature and secondary data sources. Reduction in the burden of ZnD attributable to ZAB of three staple cereals (maize, teff, and wheat) via granular and foliar Zn fertilizer applications was calculated under optimistic and pessimistic scenarios. The associated costs for fertilizer, labor, and equipment were estimated in proportion to the cropping area and compared against DALYs saved and the national Gross Domestic Product capita-1. Results: An estimated 0.55 million DALYs are lost annually due to ZnD, mainly due to ZnD-related mortality (91%). The ZAB of staple cereals via granular Zn fertilizer could reduce the burden of ZnD by 29 and 38% under pessimistic and optimistic scenarios, respectively; the respective values for ZAB via foliar application were 32 and 40%. The ZAB of staple cereals via granular fertilizer costs US$502 and US$505 to avert each DALY lost under optimistic and pessimistic scenarios, respectively; the respective values for ZAB via foliar application were US$226 and US$ 496. Foliar Zn application in combination with existing pesticide use could reduce costs to US$260-353 for each DALY saved. Overall, ZAB of teff and wheat were found to be more cost-effective in addressing ZnD compared to maize, which is less responsive to Zn fertilizer. Conclusion: ZAB of staple crops via granular or foliar applications could be a cost-effective strategy to address ZnD, which can be integrated with the existing fertilizer scheme and pesticide use to minimize the associated costs.

The One Nutrition in Complex Environments (ONCE) study protocol: a cluster-randomized multi-level multi-sectoral intervention to improve nutrition in Uganda.

OBJECTIVE: To implement and measure the effects of a multi-level multi-sectoral social behavior change (SBC) intervention in Agago District of Northern Uganda and to determine the potential for scale-up. INTERVENTION: Compare the Nutrition Impact and Positive Practice (NIPP) approach to a NIPP+ approach. The NIPP approach involves nutrition education and SBC, whereas the NIPP+ adds agricultural inputs, training, and tools to support improved farm and water quality practices. The intervention effect will be measured through lower levels of aflatoxin in grain, lower water contamination, and improved knowledge on nutrition and health. DESIGN: This is a three-arm cluster-randomized controlled superiority trial (cRCT). The study arms include the following: group 1: NIPP; group 2: NIPP+, and group 3: control. Groups 1 and 2 will receive a 12-week intervention (NIPP or NIPP+) with active monitoring and longitudinal follow-up at 2, 6, and 12 months post-intervention. Additionally, an in-depth process and performance evaluation of each intervention arm will be undertaken using quantitative and qualitative methods. A total of 60 clusters from 5 subcounties of the Agago district will be randomly selected, and 15 households per cluster will be recruited using specific inclusion/exclusion criteria for a total of 900 households (300/arm). Respondents for the qualitative portion will be purposely selected. ANALYSIS: We will collect data from all participants at 3 time points: baseline, endline, and 12 months post-intervention. The analysis will utilize intent-to-treat (ITT) using the initial randomization of the treatment arms to determine the overall impact of having the NIPP vs. NIPP+ vs. control. Mixed effects models will be used to determine the role of time-variant and invariant individual household, and community characteristics, as well as measures of exposure and integration on key outcome indicators. A difference-in-difference analysis (baseline/endline, baseline/12 months post-intervention, endline/12 months post-intervention) will also be used to triangulate findings. TRIAL REGISTRATION: NCT04209569 . One Nutrition in Complex Environments (ONCE) Registered 24 December 2019.

Soil zinc, serum zinc, and the potential for agronomic biofortification to reduce human zinc deficiency in Ethiopia.

Human zinc deficiency is a global public health problem. Many African soils are zinc deficient (ZnD), indicating fertilizers could increase crop yields and grain Zn levels, thereby increasing Zn in the food supply and alleviating human Zn deficiency. To analyze associations among soil Zn, human Zn deficiency, and child nutritional status, we combined the Ethiopian soil Zn map and the Ethiopian National Micronutrient Survey (ENMS). ENMS provides representative, georeferenced data on child nutritional status using anthropometry of children under five years old (CU5) and on human Zn deficiency among CU5 and women of reproductive age (WRA) using the recommended biomarker, serum Zn. ZnD soils mostly occur in lower altitudes, which are less populated and outside the main crop-producing areas. Serum Zn deficiencies were high, and correlated to soil Zn for children, but not for WRA. About 4 million Ethiopian CU5 are ZnD, and, of these, about 1.5 million live on low-Zn soils (< 2.5 mg/kg), while 0.3 million live on ZnD soils (< 1.5 mg/kg). Therefore, if Zn fertilizers are only applied on ZnD soils, their impact on child Zn deficiency may be limited. Greater impact is possible if Zn fertilizers are applied to soils with sufficient Zn for plant growth and if this results in increased grain Zn. Optimal soil Zn levels for plant and human nutrition may be different, and context-specific optimal levels for the latter must be determined to develop nutrition-sensitive fertilizer policies and recommendations.

Socioeconomic and health impacts of fall armyworm in Ethiopia.

Since 2016, fall armyworm (FAW) has threatened sub-Saharan 'Africa's fragile food systems and economic performance. Yet, there is limited evidence on this transboundary pest's economic and food security impacts in the region. Additionally, the health and environmental consequences of the insecticides being used to control FAW have not been studied. This paper presents evidence on the impacts of FAW on maize production, food security, and human and environmental health. We use a combination of an agroecology-based community survey and nationally representative data from an agricultural household survey to achieve our objectives. The results indicate that the pest causes an average annual loss of 36% in maize production, reducing 0.67 million tonnes of maize (0.225 million tonnes per year) between 2017 and 2019. The total economic loss is US$ 200 million, or 0.08% of the gross domestic product. The lost production could have met the per capita maize consumption of 4 million people. We also find that insecticides to control FAW have more significant toxic effects on the environment than on humans. This paper highlights governments and development partners need to invest in sustainable FAW control strategies to reduce maize production loss, improve food security, and protect human and environmental health.

The effectiveness of quality protein maize in improving the nutritional status of young children in the Ethiopian highlands.

BACKGROUND: Undernutrition is a persistent problem in Africa, especially in rural areas where the poor largely depend on staples and have limited access to a diverse diet. Quality protein maize (QPM) consists of maize varieties biofortified with increased lysine and tryptophan levels. Several studies in controlled settings have indicated the positive impact of QPM on the nutritional status of children. OBJECTIVE: Two 1-year, randomized, controlled studies were undertaken to measure the effect of QPM on the nutritional status of children consuming typical maize-based diets when QPM was cultivated by their households in the western Ethiopian highlands. METHODS: The first study used a cluster-randomized design with 151 children aged 5 to 29 months; the second study used a completely randomized design with 211 children aged 7 to 56 months. In both studies, half of the households were provided with QPM seed and the other half with seed of an improved conventional maize variety. RESULTS: Undernutrition was pervasive, and maize was the dominant food in the children's complementary diets. In the first study a positive effect of QPM was observed for weight but not height, with children in the QPM group recovering from a drop in weight-for-height. In the second study, children consuming conventional maize progressively faltered in their growth, whereas children consuming QPM did not change significantly in height-for-age and had a marginal increase in weight-for-age. CONCLUSIONS: These studies indicate that in major maize-producing and -consuming areas of Africa, home cultivation and use of QPM in children's diets could reduce or prevent growth faltering and may in some cases support catch-up growth in weight.