Peter Setimela

Political and economic features of the maize seed industry in southern Africa

ABSTRACT The seed industry in southern Africa (Angola, Malawi, Mozambique, Zambia and Zimbabwe) has three important features: first, dominance of the government as buyer and distributor of seed; second, a high market share and power of few seed companies; and third, a sustained but incomplete effort to harmonize the seed policy in the region. The challenges the seed industry is facing are lack of basic seed, poor production infrastructure, lack of skill in seed production, challenges to access and multiply seeds of varieties released from public institutions, lack of purchasing power among smallholder farmers, high transaction cost of seed marketing, market-distorting interventions by governments, lack and misuse of market information, free riding, lack of working capital financing, and breaching of contract by seed growers. Important policy implications have been drawn from this study, which include strengthening national research systems, strategic capacity building along the maize seed value chain, improving the access to financial services, developing and implementation of agreed protocols of SADC for seed policy harmonization.

Targeting of early to intermediate maize hybrids for yield performance and yield stability using SREG model

The effectiveness of targeting and predicting maize (Zea mays.L) hybrid performance is difficult when the magnitude of genotype x environment (GE) interaction and yield prediction cannot be interpreted and is only based on genotypes (G) and GE means. The traditional analysis of variance (ANOVA) is not sufficient in predicting and giving information into the patterns of genotypes and environments that give rise to GE interaction. The objectives of this study were to show the usefulness of G plus GE interaction (GGE) using the properties of GGE biplot based on the site regression (SREG) model analysis of a biplot in predicting yield performance and stability of early to intermediate maturing hybrids (EIHYB) grown in southern Africa. The SREG analysis model was based on regional trial data of EIHYB from three seasons (2005 - 2007) across 30 environments under four different management practices: well fertilized/rain fed conditions, managed nitrogen stress, managed drought stress, and managed low pH stress. GGE biplots were constructed using the first two principal components (PC1 and PC2) derived from singular value decomposition of environment-centered multi-environmental trials. The PC1 scores of the hybrids and the environments were plotted against their respective PC2 scores to effectively show mean performance and stability for grain yield across years and environments; discriminativeness vs. representativeness of test locations across the years and which-won-where. The SREG model showed that maize hybrids were under major environmental and GE interactions. In spite of large variation from year to year maize hybrids responded positively to better environmental conditions relative to grain yield performance and key environmental patterns could be established.

Complementary practices supporting conservation agriculture in southern Africa. A review

Conservation agriculture (CA)—the simultaneous application of minimum soil disturbance, crop residue retention, and crop diversification—is a key approach to address declining soil fertility and the adverse effects of climate change in southern Africa. Applying the three defining principles of CA alone, however, is often not enough, and complementary practices and enablers are required to make CA systems more functional for smallholder farmers in the short and longer term. Here, we review 11 complementary practices and enablers grouped under six topical areas to highlight their critical need for functional CA systems, namely: (1) appropriate nutrient management to increase productivity and biomass; (2) improved stress-tolerant varieties to overcome biotic and abiotic stresses; (3) judicious use of crop chemicals to surmount pest, diseases, and weed pressure; (4) enhanced groundcover with alternative organic resources or diversification with green manures and agroforestry; (5) increased efficiency of planting and mechanization to reduce labor, facilitate timely planting, and to provide farm power for seeding; and (6) an enabling political environment and more harmonized and innovative extension approaches to streamline and foster CA promotional efforts. We found that (1) all 11 complementary practices and enablers substantially enhance the functioning of CA systems and some (e.g., appropriate nutrient management) are critically needed to close yield gaps; (2) practices and enablers must be tailored to the local farmer contexts; and (3) CA systems should either be implemented in a sequential approach, or initially at a small scale and grow from there, in order to increase feasibility for smallholder farmers. This review provides a comprehensive overview of practices and enablers that are required to improve the productivity, profitability, and feasibility of CA systems. Addressing these in southern Africa is expected to stimulate the adoption of CA by smallholders, with positive outcomes for soil health and resilience to climate change.

Productivity and profitability of manual and mechanized conservation agriculture (CA) systems in Eastern Zambia

Climate variability and declining soil fertility pose a major threat to sustainable agronomic and economic growth in Zambia. The objective of this study was to assess crop yield, land and labor productivity of conservation agriculture (CA) technologies in Eastern Zambia. On-farm trials were run from 2012–2015 and farmers were replicates of a randomized complete block design. The trials compared three CA systems against a conventional practice. Yield and net return ha −1 were determined for maize and legume yield (kg ha −1 ) produced by ridge and furrow tillage, CA dibble stick planting, CA animal traction ripping and direct seeding. The dibble stick, ripline and direct seeding CA systems had 6–18, 12–28 and 8–9% greater maize yield relative to the conventional tillage system, respectively. Rotation of maize with cowpea and soybean significantly increased maize yields in all CA systems. Intercropping maize with cowpea increased land productivity (e.g., the land equivalent ratio for four seasons was 2.01) compared with full rotations under CA. Maize/cowpea intercropping in dibble stick CA produced the greatest net returns (US

DNA fingerprinting of open-pollinated maize seed lots to establish genetic purity using simple sequence repeat markers

312-767 ha −1 ) compared with dibble stick maize-cowpea rotation (US

Breeding for improved abiotic stress tolerance in maize adapted to southern Africa

204-657), dibble stick maize monoculture (US

Breeding for improved drought tolerance in maize adapted to southern Africa

108-584) and the conventional practice (US

Evaluation of early to medium maturing open pollinated maize varieties in SADC region using GGE biplot based on the SREG model

64-516). The net-return for the animal traction CA systems showed that maize-soybean rotations using the ripper were more profitable than the direct seeder or conventional ridge and furrow systems. Agronomic and economic benefits of CA-based cropping systems highlight the good potential for improved food security and agricultural productivity for smallholder farmers.

Toward a Cost-Effective Fingerprinting Methodology to Distinguish Maize Open- Pollinated Varieties

Maize (Zea mays L.) plays a dominant role in farming systems in sub-Saharan Africa (SSA). There has been a four-to-five-fold increase in the number of seed companies in SSA in the last decade, and yet more than half of small-holder farmers still grow traditional and unimproved varieties. The adoption of open-pollinated varieties (OPVs) and hybrids is around 44% of all farmers in SSA. Open-pollinated varieties are heterogeneous, and some local seed suppliers may attempt to take advantage of this to adulterate seed bags with cheaper food grain. This study sought to use a bulked DNA fingerprinting method to determine the identity and level of genetic purity among 35 seed lots of ZM521, a popular African OPV, maintained by various sources and the foundation seed source of ZM521 maintained by CIMMYT. From each seed lot, 20 individuals were bulked and analysed with 15 fluorescently labelled simple sequence repeat markers on an automatic DNA sequencer, allowing allele frequency to be determined from the bulk using peak intensity. The 35 seed lots grouped according to the source of foundation seed from which each seed lot was derived, and large genetic divergences were observed among different OPVs and hybrids.