Increasing pearl millet yields in the Sahel
“Pearl millet is one crop with the potential to adapt to the harsh conditions in the Sahel. The yield gaps, caused by mismanagement and the lack of appropriate technology, can be filled,” says Dr Fatondji Dougbedji, ICRISAT’s agronomist (soils and water conservation) based in Niger .
Organic fertilizers such as cattle manure, compost or crwsop residue have always been the principle source of nutrients for agriculture in the Sahel, particularly on small farms. But these sources are limited, because they are also in demand in construction material and as an energy source.
With farmers in the Sahel constrained to use inorganic fertilizers because of their prohibitive costs, the best way of gleaning the most from farming and the key to increased and sustained crop production lies in combining the best of the genotypic potential of a crop with optimal nutrient management.
Dr Fatondji Dougbedji and his team are currently involved in research that seeks to find ways in which these yield gaps can be filled. Under the ICRISAT-Hope project, the team has been exploring the best combination of fertilizer that would enable farmers to realize the full yield
potential of pearl millet in the region.
ICRISAT and its partners in the project have used fertilizer microdosing technology to overcome these constraints. Work began in June 2010 at ICRISAT’s station at Sadoré and the Institut National de Recherches Agronomic du Niger (INRAN) research stations. Spot application of organic fertilizer (applying small amounts to specific locations) was combined with microdoses of mineral fertilizer. Ten pearl millet genotypes were also evaluated in 2010 under a combination of four mineral and organic fertilizer management options, using a split-plot design. The goal was to realize the full potential of both fertilizers while ensuring that farmers had enough organic fertilizers for other uses.
Research revealed the acceptable levels of phosphorus and optimal levels of nitrogen and organic carbon that farmers should apply to boost initial root growth and guarantee the crop’s further growth. Genotype differences were observed at three sites in Niger
as a response to organic or mineral fertilizer application.
Though no firm conclusions can be drawn from a year’s study, Dr Fatondji is optimistic. “This is probably the best combination that affects crop responses to treatments. As we repeat this experiment on the same sites in 2011, a clearer picture will emerge of the best combinations of genotype and fertilizer, both mineral and organic, that we can then suggest to farmers to use,” he concludes.