Abstract:
Meeting current rice demand in sub-Saharan Africa (SSA) requires narrowing yield gaps on currently available
agricultural land. The objectives of this study were to decompose rice yield gaps into efficiency, resource and
technology yield gaps and to identify priority areas for research and development in the major rice production
systems (irrigated lowland, rainfed lowland, and rainfed upland) in SSA. Data were collected during the
2012–2015 wet seasons on soil properties, field operations and yields in 1529 fields at 34 sites in 20 countries
using a standardized protocol. Stochastic frontier analysis using data on biophysical environment and fertilizer
management practices together with a crop simulation model (ORYZA2000) was used to quantify the yield gap,
and efficiency, resource, and technology yield gaps. Cluster analysis was performed to classify the site-production
system combinations into yield gap groups. Actual rice yields were on average 3.8, 2.6 and 1.7 t/ha in irrigated
lowland, rainfed lowland, and rainfed upland, respectively. The yield yap ranged from 2.0–10.0 t/ha across siteproduction system combinations while the efficiency, resource, and technology yield gaps varied between 0.9 to
5.7, 0.1 to 2.3 and 0 to 7.5 t/ha, respectively. On average, efficiency, resource, and technology yield gaps
accounted for 23, 5 and 37 % of the benchmark yield (potential yield in irrigated lowland or water-limited
potential yield in rainfed lowland and upland). Four yield gaps groups were identified and were related to the
production systems, soil properties, and fertilizer application. Narrowing yield gaps requires the dissemination of
integrated crop management practices in yield gaps groups with a large efficiency yield gap, whereas, in yield
gaps groups with a large technology yield gap, the development of technologies to improve soil properties and
fertilizer use should be given priority.
