Maize In Zambia Research Articles

Is closing the agricultural yield gap a “risky” endeavor?

CONTEXTSub-Saharan Africa (SSA) has the climatic and biophysical potential to grow the crops it needs to meet rapidly growing food demand; however, agricultural productivity remains low. While potential maize yields in Zambia are 9 t per hectare (t/ha), the average farmer produces only 1–2. OBJECTIVEWe evaluate the contribution of responses to weather risk to that gap by decomposing the yield gap in maize in Zambia. While we know that improved seed and fertilizer can expand yield and profit, they may also increase the variance of yield under different weather outcomes, reducing their adoption. METHODSWe use a novel approach combining crop modeling and statistical analysis of survey data to obtain the yield gap components in Zambia driven by input cost and input risk. We use a crop model to simulate district-level marginal effects of fertilizer and seed maturity choice on the mean and variance of expected yield and profit under all-weather outcomes for each district for the past 30 years. We compare input levels that maximize expected yield to those that maximize expected profit and maximize the expected mean-variance trade-off assuming risk-aversion. To determine how much farmers' input choices are made to reduce risk, we then quantify differences in the expected riskiness of inputs by district. RESULTS AND CONCLUSIONSWe find approximately one-quarter of the yield gap can be explained by risk-reducing behavior, albeit with a substantial geographic variation. Given this finding, under present conditions, we expect that the average maximum yield that farmers can obtain without increasing risk is 6.75 t/ha compared to a potential profit-maximizing level of 8.84 t/ha. SIGNIFICANCEThe risk-related yield gap is only expected to increase with weather extremes driven by climate change. Promoting “one-size-fits all” solutions to closing the yield gap could underestimate the effect of risk mitigation on agricultural production while increasing farmers' risk exposure.

Narrowing maize yield gaps across smallholder farming systems in Zambia: what interventions, where, and for whom?

Maize production in Zambia must increase with a view towards improved food security and reduced food imports whilst avoiding cropland expansion. To achieve this, it is important to understand the causes behind the large maize yield gaps observed in smallholder farming systems across the country. This is the first study providing a yield gap decomposition for maize in Zambia, and combining it with farm typology delineation, to identify the key limiting factors to maize yield gaps across the diversity of farms in the country. The analysis builds upon a nationally representative household survey covering three growing seasons and crop model simulations to benchmark on-farm maize yields and N application rates. Three farm types were delineated, including households for which maize is a marginal crop, households who are net buyers of maize, and households who are market-oriented maize producers. Yield gap closure was about 20% of the water-limited yield, corresponding to an actual yield of 2.4 t ha− 1. Market-oriented maize farms yielded slightly more than the other farm types, yet the drivers of yield variability were largely consistent across farm types. The large yield gap was mostly attributed to the technology yield gap indicating that more efficient production methods are needed to raise maize yields beyond the levels observed in highest yielding fields. Yet, narrowing efficiency and resource yield gaps through improved crop management (i.e., sowing time, plant population, fertilizer inputs, and weed control) could more than double current yields. Creating a conducive environment to increase maize production should focus on the dissemination of technologies that conserve soil moisture in semi-arid areas and improve soil health in humid areas. Recommendations of sustainable intensification practices need to consider profitability, risk, and other non-information constraints to improved crop management and must be geographically targeted to the diversity of farming systems across the country.

Optimizing the timing of management interventions against fall armyworm in African smallholder maize: Modelling the pattern of larval population emergence and development

Since its invasion in late 2016, the fall armyworm has a widespread year-round distribution within Africa where it continues to threaten cereal production, particularly maize. Most recommended control advice emphasises the need for interventions against larvae early after colonization of a new maize crop by adults followed by a later intervention if an infestation persists. The current times for action are approximate action thresholds based on scouting which are difficult to implement as early development stages are cryptic and farmers, especially smallholders, have limited time for crop assessments. To improve the impact of controls, the modelling of early and late instar larval population emergence and development in relation to physiological time from planting was developed to enable times to action to be predicted and conveyed to farmers. The two larval population emergence models were built from field fall armyworm data from maize in Zambia and validated from similar data from multiple maize sites in Kenya. A component was included in the models to allow synchronization of maize emergence with larval development. Physiological time, in degree-days, was estimated using Earth Observation land surface temperature data sets. As precise information on action thresholds is lacking for Africa, recent published data on thresholds based on economic injury levels from Colombia were used as a guide but the models can be updated when new information becomes available for Africa. The practical implementation of the models in Africa is discussed including the outcome of some recent preliminary trials with maize farmers in Kenya.

Understanding fertilizer adoption and effectiveness on maize in Zambia

Increased fertilizer use will likely be crucial for raising and sustaining farm productivity in Africa, but adoption may be limited by ineffectiveness under certain conditions. This article quantifies the impacts of soil characteristics on maize response to fertilizer in Zambia using a nationally representative sample of 1453 fields, combining economic, farm management and soil analysis data. Depending on soil regimes, average maize yield response estimates range from insignificant (0) to 7 maize kg per fertilizer kg. For the majority of farmers, the estimated average value cost ratio is between 1 and 2, meaning fertilizer use would be fiscally rational, barring uncertainty and transfer costs. Since transfer costs exist and outcomes are uncertain, however, many farmers may sensibly pause before deciding whether to adopt fertilizer. This suggests shifting the emphasis of chronically low fertilizer use in Africa away from explanations of “market failure” toward greater emphasis onimproving fertilizer efficacy.

Evaluation of cassava processing and utilization at household level in Zambia

Cassava (Manihot esculenta Crantz) is the second most consumed staple food crop after maize in Africa and is the main food security crop after maize in Zambia. A study, aimed at analyzing cassava processing and utilization at household level in Zambia, was conducted. Surveys were conducted in five districts (Kasama, Samfya, Mansa, Serenje and Kaoma). A structured questionnaire was administered to a total of 300 randomly selected households. The percentage of households that were involved in processing were 4.3% for income, 34% for consumption and 58% for both income generation and consumption. Levels of awareness and usage of improved cassava processing methods across the districts were low, ranging between 20% and 26%. The only improved processing equipment that farmers used often (69%) was the hammer mill. Product development and utilization were still at a low level (ranging between 9% and 18%) in Zambia. Cassava is mostly consumed in its traditional form for its leaves, as a snack, and for preparing nshima (cassava flour alone or a mixture of cassava and maize meal, called maize-cassava nshima). The limited knowledge of cassava products’ diversity and the low usage of improved equipment are challenges to the production of confectionery products that could lead to increased cassava consumption. There has been no significant change over the last two decades in cassava processing and product development, which could spur cassava development. This calls for more efforts to support Government policy in diversifying crop use and crop diversification in order to create wealth.

Female access to fertile land and other inputs in Zambia: why women get lower yields

Throughout the developing world, it is a well-documented fact that women farmers tend to get lower yields than their male counterparts. Typically this is attributed to disproportionate access to high-quality inputs and labor, with some even arguing there could be a skills-gap stemming from unbalanced access to training and education. This article examines the gender-based yield gap in the context of Zambian maize producers. In addition to the usual drivers, we argue that Zambia’s patriarchal and multi-tiered land distribution system could disfavor women with respect to accessing quality soils. We are uniquely able to control for soil characteristics using farm data from a sample of 1573 fields with accompanying soil analysis. We find an expected difference in yields, but no evidence of a gap in unobserved characteristics, like skill, after controlling for access to inputs, especially quality soil, suggesting women are indeed disproportionately disadvantaged. We discuss how our findings could be used to develop self-targeting policy interventions that could empower women and would be consistent with the government’s stated equity goals.

Germplasm evaluation for climate adaptation and drought tolerance: The cases of local varieties of maize in Zambia and cowpea in Botswana

Germplasm evaluation for climate adaptation and drought tolerance: The cases of local varieties of maize in Zambia and cowpea in Botswana

Aflatoxin contamination of groundnut and maize in Zambia: observed and potential concentrations.

AimsThe aims of the study were to quantify aflatoxins, the potent carcinogens associated with stunting and immune suppression, in maize and groundnut across Zambia's three agroecologies and to determine the vulnerability to aflatoxin increases after purchase.Methods and ResultsAflatoxin concentrations were determined for 334 maize and groundnut samples from 27 districts using lateral‐flow immunochromatography. Seventeen per cent of crops from markets contained aflatoxin concentrations above allowable levels in Zambia (10 μg kg−1). Proportions of crops unsafe for human consumption differed significantly (P < 0·001) among agroecologies with more contamination (38%) in the warmest (Agroecology I) and the least (8%) in cool, wet Agroecology III. Aflatoxin in groundnut (39 μg kg−1) and maize (16 μg kg−1) differed (P = 0·032). Poor storage (31°C, 100% RH, 1 week) increased aflatoxin in safe crops by over 1000‐fold in both maize and groundnut. The L morphotype of Aspergillus flavus was negatively correlated with postharvest increases in groundnut.ConclusionsAflatoxins are common in Zambia's food staples with proportions of unsafe crops dependent on agroecology. Fungal community structure influences contamination suggesting Zambia would benefit from biocontrol with atoxigenic A. flavus.Significance and Impact of the StudyAflatoxin contamination across the three agroecologies of Zambia is detailed and the case for aflatoxin management with atoxigenic biocontrol agents provided. The first method for evaluating the potential for aflatoxin increase after purchase is presented.

Orange maize in Zambia: Crop development and delivery experience

Biofortified vitamin A “orange” maize can help address the adverse health effects of vitamin A deficiency. By 2016, HarvestPlus and its partners had developed six orange maize varieties and delivery efforts have reached more than 100,000 farming households in Zambia. HarvestPlus has established the proof of concept, that vitamin A maize varieties can be developed without compromising yield levels and that these varieties can deliver sufficient quantities of vitamin A to improve nutrition. The delivery program has also shown that farmers are willing to grow orange maize varieties and consumers are willing to buy and eat orange maize products. This paper summarizes the country’s nutritional and consumer backgrounds, the crop development and release of orange maize varieties, the delivery efforts in Zambia and impact measurement. It also synthesizes lessons learned and future challenges. Keywords: Biofortification, Vitamin A Deficiency, Orange Maize, Vitamin A Maize, Zambia

The research and implementation continuum of biofortified sweet potato and maize in Africa.

The enhancement of sweet potato and maize with provitamin A carotenoids has been part of HarvestPlus's research continuum since the formation of the biofortification project. This review includes case studies of biofortification strategies used for sweet potato in Uganda and orange maize in Zambia. The current status of the science and release of biofortified varieties was reviewed by three scientists who were part of the HarvestPlus program for more than a decade with input from a scientist who experienced orange maize dissemination in Zambia. High β-carotene varieties of sweet potato were introduced into South Africa and Mozambique, and efficacy and effectiveness studies, respectively, showed promise to improve vitamin A status, followed by dissemination efforts in Uganda. A randomized, controlled effectiveness trial tested extension models to promote sweet potato and assessed vitamin A intake among Ugandans. Orange maize breeding was initially a challenge, but considering that the carotenoid biosynthetic pathway was present in maize germplasm, breeders quickly bred higher amounts of provitamin A into the maize that was ultimately released in Zambia. Initial resistance occurred because orange maize was associated with yellow maize, which had negative connotations associated with food aid and animal feed, and consumers preferred white maize. Currently, both orange crops are available on the market.

Understanding Fertilizer Effectiveness and Adoption on Maize in Zambia

As populations continue to rise and land becomes scarcer in Africa’s rural areas, there is increasing urgency for farmers to adopt land management practices that sustainably raise land and labor productivity. Considerable effort has focused on promoting inorganic fertilizers, but it is increasingly recognized that smallholder farmers’ demand for fertilizer can be depressed by soil conditions that reduce crop response to and the profitability of fertilizer use. This article quantifies the impacts of soil characteristics on maize response to fertilizer in Zambia using a nationally representative sample of 1,453 fields. In addition to economic and farm management surveys, composite soil samples were collected and analyzed for several characteristics at the Zambia Agricultural Research Institute.

Pollen-mediated gene flow and seed exchange in small-scale Zambian maize farming, implications for biosafety assessment.

Gene flow in agricultural crops is important for risk assessment of genetically modified (GM) crops, particularly in countries with a large informal agricultural sector of subsistence cultivation. We present a pollen flow model for maize (Zea mays), a major staple crop in Africa. We use spatial properties of fields (size, position) in three small-scale maize farming communities in Zambia and estimate rates of cross-fertilisation between fields sown with different maize varieties (e.g. conventional and transgene). As an additional factor contributing to gene flow, we present data on seed saving and sharing among farmers that live in the same communities. Our results show that: i) maize fields were small and located in immediate vicinity of neighboring fields; ii) a majority of farmers saved and shared seed; iii) modeled rates of pollen-mediated gene flow showed extensive mixing of germplasm between fields and farms and iv) as a result, segregation of GM and non-GM varieties is not likely to be an option in these systems. We conclude that the overall genetic composition of maize, in this and similar agricultural contexts, will be strongly influenced both by self-organised ecological factors (pollen flow), and by socially mediated intervention (seed recycling and sharing).

Allocative and scale efficiency among maize farmers in Zambia: a zero efficiency stochastic frontier approach

ABSTRACTThe commonly used stochastic frontier model assumes that all firms are inefficient. In this specification, inefficiency is non-negative, and the probability of inefficiency being exactly zero is also zero. To the extent that efficiency varies widely across farms in under-developed economies, it is important to employ techniques that account for both inefficiency and full efficiency to ensure unbiased efficiency estimates. In this study, we employ a zero-inefficiency stochastic frontier model to examine allocative efficiency and scale economies, as well as key determinants of efficiency among Zambian maize farmers. The results show that, unlike the stochastic frontier model, the zero-inefficiency stochastic frontier model successfully allows for both fully efficient and inefficient firms to be accounted for in the estimation procedure. The estimates also reveal the presence of scale economies, with the zero-inefficiency stochastic frontier model better predicting scale efficiency compared to the stochastic frontier model. The findings also show that inefficiency is explained by the level of education, access to extension services, distance to markets and access to credit.

Creating scarcity from abundance: bumper harvests, high prices, and the role of state interventions in zambian maize markets

In 2012/13 Zambia experienced a significant spike in maize meal prices, which coincided with three consecutive years (2010 - 2012) of record maize surpluses. This seemingly paradoxical price spike occurred in the wake of a dramatic escalation of the Government’s Food Reserve Agency (FRA ) interventions in the market, with the FRA purchasing approximately 80% of the available surplus during these surplus production years. Using a case study approach, this article explores Zambia’s maize price spikes amidst years of bumper harvests. The study findings reveal that maize procurement and marketing behavior of the Government through the FRA contributed to major structural changes to the maize market: (1) A withdrawal from the market by commercial mills. By purchasing majority of the maize on the market, the FRA limited the need for commercial mills to access maize directly from the market. This reduced competition in the wholesaling sector and concentrated maize supply chain around the FRA; (2) Rationing of the FRA maize sold at subsidized prices to commercial mills. The FRA depots were unable to consistently meet the demand requirements of the commercial milling sector and as a result, some mills were prioritized in terms of receiving FRA maize. Mills that could not consistently access subsidized maize from the FRA were put at a comparative disadvantage; (3) Exit of the commercial farming sector from maize production. Between 2010 and 2013 commercial maize production in Zambia halved, from 300,000 to less than 150,000 metric tonnes. This was due t o the price uncertainty created by FRA subsidies to commercial mills, which are the traditional markets for commercial farmers, as well as significant increase in smallholder production; and (4) Squeezing the informal processing sector out of the market. B y procuring the majority of the available surplus and selling it at subsidized rates to a selected group of commercial mills, the informal market, including small- scale traders, retailers, and hammer mills, were limited in their ability to participate in the market. This in turn undermined the market channel most often used by poorer urban and rural households. These structural changes in the organization of Zambia’s maize market led to a decline in available maize supplies and reduced levels of private- sec tor competition making the market vulnerable to unanticipated demand shocks.

Assessing the promise of biofortification: A case study of high provitamin A maize in Zambia

IntroductionBiofortification is the breeding of new varieties of staple foods for increased micronutrient content. It is seen primarily as a complementary, rural-targeted strategy for better reaching remote populations. This paper presents an ex ante analysis of HarvestPlus’ provitamin A maize (PVAM) in Zambia and highlights an empirical approach based on the Zambian 2005/06 Living Conditions Monitoring Survey (LCMS). Because more than 115 countries regularly conduct a Household Consumption and Expenditure Survey (HCES), the approach developed in this LCMS-based study can be applied in many other countries to analyze varietal adoption and conduct ex ante studies. MethodsData from the LCMS and health statistics were used to characterize baseline indicators of vitamin A intake and Disability Adjusted Life Years (DALYs) lost. The introduction and scaling up of PVAM was modeled based on program plans, expert opinion and data on key adoption parameters. An adoption function was specified and expressed in terms of the percent of farmers expected to adopt PVAM over the next 30years. A logistic regression adoption function was estimated and used to identify the specific LCMS households adopting, producing and consuming PVAM each year. Information from the IFPRI International Model for Policy Analysis of Agricultural Commodities and Trade (IMPACT) of yearly maize production and demand were used to produce annual estimates of PVAM planted, harvested and consumed. Taking into account an LCMS-empirically-informed, specified market structure, individuals’ additional vitamin A intake was calculated. The number of DALYs saved were estimated using the change in vitamin A intake. Combining these estimates with cost data, the cost-effectiveness of PVAM was calculated. ResultsAssuming an adoption ceiling of 20% over 30years, implementation of PVAM will result in average additional intake of 12% of the Estimated Average Requirement (EAR), a 3 percentage point reduction in the prevalence of inadequate intake, and savings of 23% of total DALYs. Impacts are concentrated among farming households that have adopted PVAM and consume it from their own production. Their consumption will result in an average additional vitamin A intake of 172μg/day, more than 3 times the additional 54μg/day among the entire population. Among this group, the reduction in the prevalence of inadequate intake will be more than 5 times the national average (17.5 percentage points). Valuing a DALY at $1000, PVAM’s cumulative value of DALYs saved comes to exceed its cumulative total costs starting in 2019. Over 30years the cost-effectiveness of PVAM in Zambia was estimated to be $24 per DALY saved, making it very cost-effective. ConclusionThe methodologies employed in this study provide insights and inputs that can be used to target farmers who are most likely to adopt, to measure their vitamin A intake and to craft messages to promote adoption. PVAM is a long term investment that shows great promise in becoming a highly cost-effective addition to the public health arsenal for combatting micronutrient deficiencies if the 20% adoption rate can be achieved and maintained. Doing so will require effective marketing strategies, including efforts to couple this nutrition-sensitive intervention with nutrition-specific activities, such as targeted nutrition messaging and education, in order to increase the likelihood that adopting farmers will prioritize production for home consumption.

Assessing the Potential Impact and Cost-Effectiveness of Biofortified Provitamin a Maize in Zambia and High Zinc Rice in Bangladesh

Assessing the Potential Impact and Cost-Effectiveness of Biofortified Provitamin a Maize in Zambia and High Zinc Rice in Bangladesh

Creating scarcity from abundance: Bumper harvests, high prices, and the role of state interventions in Zambian maize markets

In 2012/13 Zambia experienced a significant spike in maize meal prices, which coincided with three consecutive years (2010 - 2012) of record maize surpluses. This seemingly paradoxical price spike occurred in the wake of a dramatic escalation of the Government’s Food Reserve Agency (FRA) interventions in the market, with the FRA purchasing approximately 80% of the available surplus during these surplus production years. Using a case study approach, this article explores Zambia’s maize price spikes amidst years of bumper harvests. The study findings reveal that maize procurement and marketing behavior of the Government through the FRA contributed to major structural changes to the maize market: (1) A withdrawal from the market by commercial mills. By purchasing majority of the maize on the market, the FRA limited the need for commercial mills to access maize directly from the market. This reduced competition in the wholesaling sector and concentrated maize supply chain around the FRA; (2) Rationing of the FRA maize sold at subsidized prices to commercial mills. The FRA depots were unable to consistently meet the demand requirements of the commercial milling sector and as a result, some mills were prioritized in terms of receiving FRA maize. Mills that could not consistently access subsidized maize from the FRA were put at a comparative disadvantage; (3) Exit of the commercial farming sector from maize production. Between 2010 and 2013 commercial maize production in Zambia halved, from 300,000 to less than 150,000 metric tonnes. This was due to the price uncertainty created by FRA subsidies to commercial mills, which are the traditional markets for commercial farmers, as well as significant increase in smallholder production; and (4) Squeezing the informal processing sector out of the market. By procuring the majority of the available surplus and selling it at subsidized rates to a selected group of commercial mills, the informal market, including small-scale traders, retailers, and hammer mills, were limited in their ability to participate in the market. This in turn undermined the market channel most often used by poorer urban and rural households. These structural changes in the organization of Zambia’s maize market led to a decline in available maize supplies and reduced levels of private-sector competition making the market vulnerable to unanticipated demand shocks. Keywords: Maize, price spikes, bumper harvests, subsidies, markets, traders, agriculture, Zambia

Hybrid Seed and the Economic Well-Being of Smallholder Maize Farmers in Zambia

The development and diffusion of hybrid maize in Zambia since the 1970s is a major achievement in African agriculture, but other than profitability studies, analyses of how this process has affected the economic well-being of smallholder farmers have been few. We test the relationship of hybrid seed use with six indicators of economic well-being. After using the control function/instrumental variables approach to test for the endogeneity of hybrid seed use, we estimate correlated random effects (CRE) fractional response, CRE Tobit, and fixed effects models with a panel of nationally representative data collected in 2002/3 and 2006/7. Findings suggest that use of maize hybrids is associated with higher values of household income, assets, farm and processing equipment, and livestock, and less deprivation compared to other farmers in nearby villages.

Epidemic significance of planting time and hybrid on Fusarium infection of maize in two agroecological zones of Zambia

Most hybrid maize samples from three years of field experiments in Zambia contained Fusarium spp., but there were differences between hybrid susceptibility in two agroecological zones. Mean annual kernel infection ranged from 14 to 63% in the medium rainfall zone (MRZ). In the high rainfall zone (HRZ), the highest mean annual infection recorded was 18%. A Partial Least Square (PLS) analysis showed negative relationship between Fusarium kernel infection and rainy days before midsilk and positive relationship between Fusarium kernel infection and number of dry weeks between planting and midsilk. Fusarium verticillioides was most frequently isolated, and the highest incidences and levels were found in the MRZ. Other species detected included: Fusarium subglutinans, Fusarium oxysporum, Fusarium graminearum, Fusarium compactum, Fusarium equiseti, Fusarium proliferatum, Fusarium nygamai, Fusarium semitectum and Fusarium anthophilum. This is the first report of the presence of F. compactum, F. nygamai and F. anthophilum in maize in Zambia.

The effects of the Food Reserve Agency on maize market prices in Zambia

AbstractOver the last decade, governments throughout eastern and southern Africa have increasingly used strategic reserves and/or marketing boards to influence grain market outcomes, yet little is known about how these activities are affecting grain markets. This article estimates the effects of the Food Reserve Agency (FRA) on maize market prices in production and consumption regions in Zambia using a vector autoregression model and monthly data from July 1996 through December 2008. In recent years, FRA has become the dominant buyer of smallholder maize in Zambia. Simulations show that FRA activities stabilized market prices throughout the July 1996–December 2008 study period and raised mean prices between July 2003 and December 2008 by 17–19%. The price raising effects of FRA policies have assisted surplus maize producers but adversely affected net buyers of maize in Zambia, namely urban consumers and the majority of the rural poor. The increase in maize price stability is unlikely to have had substantial welfare effects on poor households. In contrast, relatively wealthy producers are likely to have benefited from the higher average and more stable maize prices resulting from FRA policies.