Moringa oleifera (moringa) trees excel mainly in tropical and sub-tropical regions and are known to thrive in a wide range of soil types. The recent rise in moringa production in various agro-ecological zones of South Africa could be attributed to its multiple benefits, including nutritional and medicinal properties. Since its introduction as a cultivated crop, there has been a growing interest from farmers, researchers and government on various aspects of the tree such as its morphology, chemistry, growing conditions, production, processing and utilisation. We reviewed the work done on moringa within the South African context in terms of production, growing conditions and cultivation practices. The involvement of government departments on moringa-oriented activities and its consumption as food were also reviewed. In addition, gaps were outlined on its utilisation that need to be addressed, and recommendations provided on what could be done to ensure successful production of moringa in South Africa.

The extensive use of synthetic chemical fertilizers is associated with environmental pollution and soil degradation. In addition, the high costs of these fertilizers necessitate the search for alternative, eco-friendly and safe natural sources of phytonutrients. The liquid extracted from moringa (Moringa oleifera Lam.) leaves has been used in agriculture to improve the growth and productivity of several crops. The efficacy of moringa leaf extract (MLE) is attributed to its high content of mineral nutrients, protein, vitamins, sugars, fiber, phenolics and free proline. In addition, MLE contains significant amounts of phytohormones, such as auxins, cytokinins and gibberellins. Furthermore, MLE is a valuable product promoting seed germination, plant growth and deeper root development, delaying fruit senescence and increasing the yield and quality of crops grown under normal or stressful conditions. Here, we review the research on MLE as a biostimulant to enhance crop growth and productivity. Moreover, we emphasize its possible introduction to smallholder farming systems to provide phytonutrients, and we further highlight research gaps in the existing knowledge regarding MLE application. Generally, MLE is an inexpensive, sustainable, eco-friendly and natural biostimulant that can be used to improve the growth and productivity attributes of various crops under non-stressful and stressful conditions.

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Spider plant (Cleome gynandra) is predominantly used as a traditional leafy vegetable throughout Africa and is considered a rich natural source of essential nutrients such as vitamins, minerals and proteins. With the increase in malnutrition, diet related non-communicable diseases and poverty across the continent of Africa, the spider plant is a bona fide alternative healthy food crop to alleviate these challenges. Spider plant is an erect annual herb that could grow up to 150 cm tall, strongly branched, with a long taproot and few secondary roots. It is commonly consumed in resource-poor communities especially during times of major food scarcity. It is a drought-tolerant and resilient annual vegetable crop capable of growing well in a wide range of climatic and edaphic conditions. Despite the potential benefits and wide adaptability, progressive attempts towards the development of C. gynandra as a crop have been impeded by issues like low investment in research and development resulting in poor seed quality, relatively low yields and susceptibility to pests and diseases. In this paper, we reviewed the research that has been done regarding its morphology, growing conditions, production and utilisation (i.e., nutrition). The current review highlighted the status of the science in advancing the domestication of C. gynandra as a potential power crop for several African countries. The review concluded that with the advancement of modern biotechnology techniques and genome sequencing, there is a compelling case for investment and development in C. gynandra as a candidate for managing micronutrient deficiencies during the post-pandemic era. Finally, the existing knowledge gaps (e.g., breeding) that necessitate explorations were identified and recommendations that could enhance its development and potential commercialisation were made.