Seed certification and maize, rice and cowpea productivity in Nigeria: An insight based on nationally representative farm household data and seed company location data

Despite the potential importance of seed quality to agricultural productivity growth, many governments in sub-Saharan Africa lack the capacity to expand quality assurance systems even where there is expressed interest. This study aims to evidence the value of quality assurance systems with an analysis of efforts to produce and distribute certified seed in Nigeria. We assess the associations between quantities of certified seeds produced and spatial variations in production locations proxied by headquarter locations of seed companies producing certified seeds, on the one hand, with spatial variations in the use of certified seed, yields, and output at the farm level, on the other hand. Our analysis covers three crops that are important to food security in Nigeria: maize, rice, and cowpea. Our analysis integrates information on seed quantities produced and locations of seed companies with nationally representative panel data from a survey of farm households and spatially explicit rainfall and temperature data. We find a positive relationship between certified seed production in proximity to farm households and farm-level use of certified seeds, yields, and output, although this effect is diminishing at the margin. These diminishing marginal effects may be partly due to two factors. First, the yield gains from certified seeds tend to vary considerably within each state, suggesting that either quality issues persist in the seed supply chain or farmers are not using complementary inputs or appropriate management techniques when using quality seed. Second, it may be that as certified seed becomes more available to farmers, its use spreads from higher-return farms to lower-return farms, thereby diminishing the gains on the extensive margin. Although more rigorous assessments of causal effects and cost-effectiveness are needed to validate these findings, these results are consistent with the hypothesis that there are diminishing returns to seed quality assurance. Policymakers, regulators, and seed providers may benefit from identifying optimal, crop-specific target quantities or rates for certified seed production rather than aiming for certification of all seed produced in a market

Impacts of climate and price changes on global food production

Agriculture is one of the key drivers and victims of climate change. Climate-resilient agriculture is therefore vital for achieving enhanced food security—which is a crucial component of the sustainable development goals (SDGs). This paper provides answers to questions that are prerequisite for policies that address agriculture and climate change. We analyze the determinants of global average crop production for maize, wheat, rice, and soybeans over the period 1961–2013. We find strong and statistically significant supply elasticities for all four crops with respect to own crop prices. Our results also underscore the relevance of output price volatility for the supply of these key global agricultural staple crops—especially on production of wheat and maize. Comparing the standardized effect sizes of own price and price volatility estimates, the effects are on par for wheat production while the price volatility effect is only a fifth of the own price effect on maize production. In agreement with previous studies, we also find that climate change has significant adverse effects on production of the world’s key staple crops. More importantly, this study finds that weather extremes—both in terms of temperature and precipitation shocks— during the growing months have significant adverse impacts on the production of the abovementioned food crops. Price and weather extremes do not only adversely affect average global food production, they also positively contribute to the year-to-year fluctuations of food availability. Thus, combating climate change using both mitigation and adaptation technologies is crucial for global production and hence food security