Assessing the potential of dual-purpose maize in southern Africa: A multi-level approach

Abstract

a b s t r a c tThis paper explores the potential and challenges of increasing production of food and feed on existing maize fields in mixed crop-livestock systems in the semi-arid areas of southern Africa. It integrates results from different sources of data and analysis: 1. Spatial stratification using secondary data for GIS layers: Maize mega-environments combined with recommendation domains for dual-purpose maize were constructed for Malawi, Mozambique and Zimbabwe, stratifying the countries by demand factors (livestock densities and human population densities) and feed availability. Relative biomass contributions to feed resources from rangelands were compared to those from croplands to explore the usefulness of global datasets for feed supply estimations. 2. Verification through farming systems analysis: the potential demand for maize residues as feed (maize cropping patterns, maize yields and uses, feed deficits) was compared at contrasting sites, based on household survey data collected on 480 households in 2010. 3. Maize cultivar analysis: Genotypic variability of maize cultivars was compared to evaluate the potential contribution (stover quantity and quality) of dual-purpose maize to reduce feed deficits. The study results illustrate high spatial variability in the demand for and supply of maize residues. Northern Malawi is characterized by high livestock density, high human population density and high feed availability. Farmers achieve maize yields of more than 2 t/ha resulting in surplus of residues. Although livestock is important, southwest Zimbabwe has low livestock densities, low human populations and low feed availability; farming systems are more integrated and farmers make greater use of maize residues to address feed shortages. Central Mozambique also has low cattle densities, low human populations and low feed availability. More rangelands are available but maize yields are very low and livestock face severe feed shortages. The investigation of 14 advanced CIMMYT maize landraces cultivars and 15 advanced hybrids revealed significant variations in grain and stover yield and fodder quality traits. Where livestock densities are high and alternative feed resources are insufficient, maize cultivars with superior residue yield and fodder quality can have substantial impact on livestock productivity. Cultivars at the higher end of the quality range can provide sufficient energy for providing livestock maintenance requirements and support about 200 g of live weight gain daily. Maize cultivars can be targeted according to primary constraints of demand domains for either stover quantity or stover fodder quality and the paper proposes an approach for this based on voluntary feed intake estimates for maize stover.

Genome wide association study and genomic prediction for stover quality traits in tropical maize (Zea mays L.)

“…Considerable progress has been made in detecting and exploiting genetic variations in stover fodder quality in maize. Screening of many of the released and pipeline hybrids of maize for stover quality has resulted in the identification and preferential promotion of dual-purpose hybrids across the globe, including USA 43 , Mexico 44 , Ethiopia and Tanzania 9 , South Africa 45 and South Asia 8 , 32 , 46 However, targeted breeding for these dual purpose (grain and stover) maize would entail additional phenotyping and increase in cost of the breeding pipeline, a major bottleneck for whole plant improvement for multiple traits. Use of molecular markers circumventing the need for additional phenotyping could support breeders in early selections of genotypes with superior yields and stover quality.…”

Hydroeconomic Analysis to Guide Climate Adaptation Plans

“…Water transpires, evaporates, leaks, and seeps all four of which make it difficult to establish private property rights, build infrastructure, enact comprehensive legislation governing its development and use, or get to people at the time, place, and form in which they need it. Even today, water has a low ratio of value to weight as it moves through the hydrologic cycle (Tui et al, 2013;Kovacs and Durand-Morat, 2020;Slater et al, 2020).…”

From Best Fit Technologies to Best Fit Scaling: Incorporating and Evaluating Factors Affecting the Adoption of Grain Legumes in Sub-Saharan Africa

“…Humid and Dry, Warm and Cool, Low population density and High population density) based on thresholds appropriate for the indicator and country. We combined the reclassified binary indicators to create domains (ASARECA, 2005;Homann-Kee Tui et al, 2013;Notenbaert et al, 2013;Okike et al, 2000;Weber et al, 1996) in which we could test N2Africa technologies, practises and models (Kristjanson et al, 2002). The combination of factors resulted in eight possible adoption domains (Table 3) for each crop per country due to the different market access models.…”