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Efforts to mitigate the negative impacts of flooding on rice production have focused mainly on varietal improvement. However, there is the need to find a technological fit between genotypes and nutrient management strategies to ensure sustainable production in submergence-prone areas. During the 2016 and 2017 growing seasons, we compered effectiveness and resilience of the traditional farmer practice of rice fertilization (FP), where fertilizers are surface broadcast, with three fertilization strategies commonly used in rice production systems to determine the most efficient fertilization strategy for submergence-prone rice production areas in northern Ghana. The fertilization strategies were (i) urea deep placement technology (UDP), (ii) microdosing (MD) and (iii) modification of the farmer practice (MFP), where fertilizers are soil-incorporated. Two submergence-tolerant rice varieties, NERICA L-19 and NERICA L-49 were used as test varieties. Compared to production under non-submergence conditions, UDP resulted in <30% decrease in grain yield under submergence conditions; MFP by 57%, MD by 60% and FP by 75%. In submergence-prone areas, agronomic efficiency increased by 4.4× in UDP, relative to FP, 1.7× in MFP, and 1.5× in MD. Only UDP resulted in positive gross profit margin for rice production under submergence conditions. All other fertilization strategies resulted in negative gross profit margin values. From the combined results we conclude that under submergence-prone environment UDP is the most effective and resilient fertilization strategy for rice production and that farmers will realize profitable return on their investment with a combined use of submergence-tolerant rice cultivars and UDP fertilization strategy. [ABSTRACT FROM AUTHOR]

Farmers in the inland valleys of northern Ghana are challenged with nitrogen (N) deficiency as a major production constraint of rainfed lowland rice ( Oryza sativa L.). With extremely low use of external inputs, there is a need to efficiently use the systems' internal resources such as native soil N. Largest soil nitrate-N losses are expected to occur during the transition between the dry and wet season (DWT) when the soil aeration status changes from aerobic to anaerobic conditions. Technical options avoiding the build-up of nitrate are expected to reduce N losses and may thus enhance the yield of rice. A field study in the moist savanna zone of Ghana assessed the in situ mineralization of native soil N, the contribution of nitrate to the valley bottom by sub-surface flow from adjacent slopes, and the effects of crop and land management options during DWT on seasonal soil Nmin dynamics and the yield of lowland rice. Large amounts of nitrate accumulated during DWT with a peak of 58 kg ha−1 in lowland soils, of which 32 kg ha−1 were contributed from the adjacent upland slope. Most of this nitrate disappeared at the onset of the wet season, possibly by leaching and denitrification upon soil flooding. While the incorporation of rice straw (temporary immobilization of soil N in the microbial biomass) had little effect on soil N conservation, growing a crop during DWT conserved 22-27 kg of soil N ha−1 in the biomass and Crotalaria juncea supplied an additional 43 kg N ha−1 from biological N2 fixation. Farmers' practice of bare fallow during DWT resulted in the lowest rice grain yield that increased from 1.3 (2.2) to 3.9 t ha−1 in case of the transition-season legume. Growing a pre-rice legume during DWT appears a promising option to manage N and increase lowland rice yields in the inland valleys of northern Ghana. [ABSTRACT FROM AUTHOR]

Production of Bird’s eye chillies (Capsicum annuumL) under tropical conditions presents a unique opportunity for small farmers to improve income. A study in 2010 and 2011 evaluated the performance of irrigated, improved Bird’s eye chilli (BEC), cvs. Demon, UHP281 70, UHP226 94, and UHP296 92, with ‘Shito Adope’, for growth, adaptability, yield, and marketability. The cultivars are categorized as being early (‘UHP281 70’ and ‘Shito Adope’), medium (‘UHP226 94’ and ‘Demon’), and late maturing (‘UHP296 92’). The UHP series had the best yield (average 12.47 Mt·ha−1). The best choice for crop performance and dried fruit quality/brightness and perceived marketability was ‘UHP281 70’ followed by ‘UHP226 94’. Economic analysis indicated that ‘UHP296 92’ had the highest total variable cost. It also had the highest marginal rate of returns (217%). It is possible to increase options for small-, medium-, and large-scale chilli pepper farmers regarding choice of superior Bird’s eye chilli peppers. [ABSTRACT FROM PUBLISHER]

Abstract: Reducing fallow periods with sown leguminous plants (i.e., Callopogonium mucunoides) was found to be a technically feasible, low-input method of improving soil nutrient levels for rice cropping in the Guinea and Sudan savannah regions of northern Ghana. However, farmers and policy makers are particularly interested in understanding whether the new rice production technology can be substituted for the traditional rice cropping systems within a whole-farm plan context and, if so, what are the likely resource allocation and financial implications to farmers. An optimal whole-farm plan that incorporates traditional (bush fallow) cropping of rice, jointly with livestock production was generated using a linear programming model, and then used to assess the economic implications of introducing the improved fallow (i.e., incorporating Callopogonium mucunoides) rice cropping system. The alternative combinations of enterprises investigated needed to be economically viable household farm units, as well as meet household food security requirements of such resource poor farmers. Introducing the new rice production technology into a base whole-farm model (i.e., under traditional rice cropping) increased rice area by 45%, and farm income above variable costs by 34%. In addition, the representative farm raises six beef cows and 72 poultry birds. In sensitivity analyses of alternative model scenarios, farm incomes were higher and more stable for farming systems using the new rice cropping technology than with the traditional whole-farm model. More widespread adoption of the new rice-based production technology will help transform existing traditional subsistence farming systems to more profitable commercial production systems. This transformation will have implications for farm structure (in terms of consolidation of highly fragmented holdings), agricultural resource management, and property rights (such as recognition of individualized rights to cropland, livestock grazing land and agricultural water resources). [Copyright &y& Elsevier]