Protected cultivation of vegetable crops in sub-Saharan Africa: limits and prospects for smallholders. A review

Abstract

Vegetable production in sub-Saharan Africa faces numerous agronomic constraints that will have to be overcome to feed the increasing population and to fight malnutrition. Technology transfer and the adoption of low-tech protected cultivation techniques affordable for smallholders are believed to be able to meet this challenge. Protected cultivation techniques are a set of agricultural practices aimed at artificializing the crop environment through the use of soil covers and/or plant covers to control pests and climatic conditions. Although protected cultivation techniques may increase the yield and quality of vegetable crops and extend their production periods worldwide, the transfer of these techniques in sub-Saharan Africa raises questions about their agronomical performances, their profitability but also their environmental impacts. Are low-tech protected cultivation techniques adapted to the sustainable production of vegetables by smallholders in sub-Saharan Africa? To answer this question, we present an overview of the agronomic, economic, and environmental performances of low-tech protected cultivation techniques in sub-Saharan Africa as reported in the literature. The major conclusions that can be drawn from the review are (1) low-tech protected cultivation techniques are not suitable in all climatic conditions in sub-Saharan Africa and need to be combined with other methods to ensure adequate pest control, (2) the profitability of protected cultivation techniques relies on the capacity to offset increased production costs by higher yields and higher selling prices to be obtained with off-season and/or higher quality products, (3) breaking with existing cropping systems, the lack of technical support and skills, and the limited access to investment funding are major obstacles to the adoption of protected cultivation techniques by smallholders (4) life cycle assessments conducted in northern countries suggested that more efficient use of agricultural inputs would offset the negative impacts of protected cultivation techniques if they are properly managed, but further studies are required to be sure these results can be extrapolated to sub-Saharan Africa context. (Résumé d'auteur

Management of Heat Stress in Tomato Seedlings under Arid and Semi-Arid Regions: A Review

“…Due to many environmental problems, the protected cultivation has established to overcome these problems. It could be defined the protected agriculture or cultivation as a group of agricultural practices, which allows to produce the cultivated crop in plastic-or glass-house to protect plants fromclimatic conditions and pests (Nordey et al 2017 andGhani et al, 2019). This protected cultivation could be considered as a "sustainable solution" in producing the foods particularly in hot-arid environments (Ghani et al, 2019).…”

Mitigation of climatic conditions and pest protection provided by insect-proof nets for cabbage cultivation in East Africa

“…Replacing the use of pesticides by netting to protect vegetable crops from insect pests has been the subject of several studies in SSA (Nordey et al, 2017). Many reports indicated that the use of insect-proof nets increased yield and prevented infestation by the largest pests in size, that is, Lepidoptera and Diptera, of several vegetable crops, including French beans (Gogo et al, 2014), tomato (Saidi et al, 2013), and cabbage (Kiptoo et al, 2015;Simon et al, 2014;Martin et al, 2006).…”

“…Many reports indicated that the use of insect-proof nets increased yield and prevented infestation by the largest pests in size, that is, Lepidoptera and Diptera, of several vegetable crops, including French beans (Gogo et al, 2014), tomato (Saidi et al, 2013), and cabbage (Kiptoo et al, 2015;Simon et al, 2014;Martin et al, 2006). However, the use of netting by producers in the tropics is hindered by the resulting increase in temperature in the tunnels that can be detrimental to crop development (Simon et al, 2014;Nordey et al, 2017).…”

Discrimination of Tomato Plants (Solanum lycopersicum) Grown under Anaerobic Baffled Reactor Effluent, Nitrified Urine Concentrates and Commercial Hydroponic Fertilizer Regimes Using Simulated Sensor Spectral Settings

“…Subsequently, the improvement of crop production which leads to food security has been amongst the principal priorities required to fulfil the goals of sustainable human development as well as the African Union's Agenda 2063 [5]. Furthermore, food demand is anticipated to triple in sub-Saharan Africa after the projected 2.5-fold increase in population increase [6]. Specifically, a 60% increase in agricultural and horticultural production will be required by the increasing population in the light of diminishing water and soil nutrient resources [6].…”

“…Furthermore, food demand is anticipated to triple in sub-Saharan Africa after the projected 2.5-fold increase in population increase [6]. Specifically, a 60% increase in agricultural and horticultural production will be required by the increasing population in the light of diminishing water and soil nutrient resources [6]. The major concern is the current dietary transition, which is in favour of vegetables such as tomatoes amongst other crops, which is projected to increase, especially in urban areas, while water and soil nutrients are in decline [6][7][8].…”