Maize is a major source of food security and economic development in sub-Saharan Africa (SSA), Latin America, and the Caribbean, and is among the top three cereal crops in Asia. Yet, maize is deficient in certain essential amino acids, vitamins, and minerals. Biofortified maize cultivars enriched with essential minerals and vitamins could be particularly impactful in rural areas with limited access to diversified diet, dietary supplements, and fortified foods. Significant progress has been made in developing, testing, and deploying maize cultivars biofortified with quality protein maize (QPM), provitamin A, and kernel zinc. In this review, we outline the status and prospects of developing nutritionally enriched maize by successfully harnessing conventional and molecular marker-assisted breeding, highlighting the need for intensification of efforts to create greater impacts on malnutrition in maize-consuming populations, especially in the low-and middle-income countries. Molecular marker-assisted selection methods are particularly useful for improving nutritional traits since conventional breeding methods are relatively constrained by the cost and throughput of nutritional trait phenotyping.

Core Ideas These selected varieties were compared with the best commercial check varieties on‐farm across 94 locations in eastern and southern Africa in a randomized complete block design with three replications for two seasons. The new drought tolerant hybrids showed a yield advantage over the commercial check varieties both in the early and medium‐late maturing categories by 4 to 19%. Among the CIMMYT hybrids, CZH0616 showed wide adaptation under stress and non‐stress conditions, making it an ideal genotype for smallholders’ farmers. Under farmers’ fields CZH0616, CZH0837, CZH0935, and CZH0928 were high yielding and stable across locations in eight countries that represent major maize production environments in eastern and southern Africa. Maize (Zea mays L.) is the most important staple food in eastern and southern Africa (ESA) with human maize consumption averaging 91 kg capita−1 yr−1. Current maize yield averages 1.2 t ha−1 and is barely sufficient for the region’s requirements due to drought and low N stresses. The objective of this study was to compare new drought tolerant (DT) maize hybrids and open pollinated varieties (OPVs) against the best commercial varieties in ESA under farmer management conditions and to validate on‐station results. Maize varieties were simultaneously selected on‐station in four types of environments across 44 locations in ESA during the 2008/2009 and 2009/2010 seasons. During the 2010/2011 and 2011/2012 seasons, 20 promising DT maize hybrids and OPVs were selected from the on‐station based on their mean grain yield and stability. These selected varieties were compared with the best commercial check varieties on‐farm across 80 locations in ESA in a randomized complete block design for two seasons. The genotype + genotype × environment comparison biplot showed variety CZH0616 together with other new DT hybrids to be stable and high yielding across 44 locations on‐station in the ESA region compared to the commonly grown checks such as SC513. The new DT hybrids showed a yield advantage over the commercial check varieties both in the early and medium‐late maturing categories by 4 to 19%, and the gains were bigger under stress conditions. Under farmers’ fields CZH0616, CZH0837, CZH0935, and CZH0928 were high yielding and stable across locations.

Maize (Zea mays) is the most important cereal crop in Zimbabwe and is grown by both large‐ and small‐scale farmers who are located in different agro‐ecological zones of the country. The development and dissemination of adapted and high‐yielding maize cultivars to these agro‐ecological zones involves conducting multi‐environment trials (METs). This study was conducted with the objectives of i) understanding complex G × E interaction and stability of single cross hybrids generated using CIMMYT elite drought tolerant lines and Department of Research and Specialist Services (DR&SS) elite drought susceptible lines for grain yield across stress and nonstress environments and ii) to identify genotypes to recommend for further use in the breeding program. Initially, yield data of 80 maize single cross hybrids tested across seven environments during the 2009 to 2010 and 2010 to 2011 seasons were analyzed using the additive main effects and multiplicative interaction (AMMI) biplot method. The analysis was further done for 20 best performing genotypes to facilitate less congested graphical presentation. Combined analysis of variance showed highly significant differences for the G × E interaction, indicating the possibility of selection for stable genotypes. The five AMMI interaction principal component analyses (IPCAs; IPCA1, IPCA2, IPCA3, IPCA4, and IPCA5) explained 82.41% of the variation and they were highly significant. The results showed three genotypes with high yield performance and broad adaptability whilst narrow adaptations were also observed. Agricultural Research Trust Farm was the most powerful site in discriminating among genotypes and the most representative environment.

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Macro and micronutrient deficiencies pose serious health challenges globally, with the largest impact in developing regions such as subSaharan Africa (SSA), Latin America and South Asia. Maize is a good source of calories but contains low concentrations of essential nutrients. Major limiting nutrients in maize-based diets are essential amino acids such as lysine and tryptophan, and micronutrients such as vitamin A, zinc (Zn) and iron (Fe). Responding to these challenges, separate maize biofortification programs have been designed worldwide, resulting in several cultivars with high levels of provitamin A, lysine, tryptophan, Zn and Fe being commercialized. This strategy of developing single-nutrient biofortified cultivars does not address the nutrient deficiency challenges in SSA in an integrated manner. Hence, development of maize with multinutritional attributes can be a sustainable and cost-effective strategy for addressing the problem of nutrient deficiencies in SSA. This review provides a synopsis of the health challenges associated with Zn, provitamin A and tryptophan deficiencies and link these to vulnerable societies; a synthesis of past and present intervention measures for addressing nutrient deficiencies in SSA; and a discussion on the possibility of developing maize with multinutritional quality attributes, but also with adaptation to stress conditions in SSA.