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Bambara groundnut is vital for food security due to its high nutritional content and resilience to environmental stresses. The objectives of the study were to determine associations among agronomic traits and nutrients in Bambara groundnut and identify traits influencing grain production in Bambara groundnut. Field experiments were conducted at the University of KwaZulu-Natal's Ukulinga Farm and Controlled Environment Facility (CEF) to assess agronomic performance and nutritional content. Nutritional content was evaluated using standard combustion procedures and electron microscopy. Correlation, regression, and path coefficient analyses revealed varying relationships among agronomic traits, nutrient content, and grain yield. The number of seeds (NS), healthy seeds (NHS), and plant height (PH) exhibited significant associations with grain yield. Neutral detergent fiber (NDF), starch, magnesium (Mg), nitrogen (N), oxygen (O), and phosphorus (P), were the key predictors of grain yield productivity. Path coefficient analysis showed that NS, PH and magnesium, oxygen, and carbon contents positively affected grain yield. In conclusion, grain yield was influenced by multiple traits through different pathways that are complicated by the growing environment. Selecting taller genotypes with good agronomic traits and high nutrient content is recommended to develop high yielding Bambara groundnut cultivars. [ABSTRACT FROM AUTHOR]

We investigated the trajectory of depressive symptoms ("depression") from the start of the COVID-19 pandemic in South Africa (March 2020) until 2021, between individuals with and without pre-pandemic depression, specifically regarding the role of food security. Our investigation used publicly available panel data (N = 6,930) from the South African National Income Dynamics Study Coronavirus Rapid Mobile Survey (SA-NIDS-CRAM from 2020–2021) on those who had also participated in the pre-pandemic South African National Income Dynamics Study (SA-NIDS, 2017) depression interview. We investigated trends in depressive symptomatology (based on a 2-item Patient Health Questionnaire) at SA-NIDS-CRAM Wave 2 (July 2020), Wave 3 (February 2021) and Wave 5 (May 2021). Generalized estimating equations (GEE) with post-estimation linear combinations of estimators were fitted to investigate the roles of pre-pandemic depression (based on 2017 SA-NIDS data) and food insecurity during the pandemic on depressive symptomatology. During the pandemic, the highest levels of depression were observed consistently among those with pre-pandemic depression and food insecurity; and were lowest among those without pre-pandemic depression and food security. Depressive symptomatology rose in nearly equal magnitude during the early phases of the pandemic in two groups: those without pre-pandemic depression but food insecure during the pandemic; as well as those with pre-pandemic depression but food secure during the pandemic. However, this dynamic changed later in the pandemic, when higher depressive symptomatology was observed in the group with both pre-pandemic depression and food insecurity, widening the gap between them from Wave 3 (adj β = 0.63, p < 0.01) to Wave 5 (adj β = 0.79, p < 0.01). Our results highlight the importance of addressing both population mental health and food insecurity, particularly at the early stages of a crisis/disaster. As we showed that mental health impact is linked to food insecurity during a pandemic, strengthening social protection measures, especially around food and nutrition, would help build resilience to crises in the long term. [ABSTRACT FROM AUTHOR]

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Field experiments were carried out during the summer/autumn (first trial) and winter/spring (second trial) seasons of 2019 and 2021 in the Dlangubo, Ngwelezane, and Mtubatuba areas of KwaZulu-Natal Province of South Africa to study the drought amelioration effects and impact of two locally available organic wastes (filter cake—a residue derived from sugar cane filtration (FC) and macadamia husk compost (MHC)) on the productivity and physiological responses of four orange-fleshed sweet potato cultivars (Beauregard cv., Impilo, W-119 and 199062.1). The effects of FC and MHC were compared with that of inorganic fertilizer (IF) [2:3:2 (30)], FC + IF, MHC + IF, and the control. The soil amendments were applied in the first trials only. Climatic data such as humidity, temperature, and rainfall were taken via remote sensing. The results of the first trial indicated that filter cake and IF significantly performed better than MHC. The strength of filter cake may be attributable to its rich array of mineral nutrients such as calcium, magnesium, potassium, sodium, zinc, copper, manganese, iron, and phosphorus. The limited performance of MHC may be attributable to its ability to hold water. Furthermore, a positive correction occurred between the yield of the test orange-fleshed sweet potato (OFSP) cultivars, rainfall, and vegetation indices (normalized difference vegetation index, enhanced vegetation index, and normalized difference water index) investigated in the study. In season two, IF treatment did not have any significant effect on the growth and productivity of any of the tested sweet potato cultivars, but, FC, FC + IF, and MHC treatments largely maintained their performances. In conclusion, the use of FC is highly recommended in the production of the test OFSP cultivars. Furthermore, the study indicates that both FC and MHC may not only supply the needed plant nutrients but has the capacity to reduce the impact of drought on the growth of the test cultivars. These findings are of great value to farmers, especially the resource-poor ones. [ABSTRACT FROM AUTHOR]

Ethnopedological studies focus on agricultural soils resulting in undervaluation of non-agricultural soil materials during land classification. In this study, ethnographic and ethnopedologic methods were used to obtain local knowledge and gain in-depth understanding of non-agricultural soils, their mineralogical and elemental composition relating to application in geophagy, healing and cosmetic purposes in two villages in KwaZulu-Natal, South Africa. In each village a questionnaire was administered to fifty randomly selected individuals from which ten knowledgeable volunteers (including eight geophagists from two villages) provided details on the selection criteria, the desired properties and why the soils performed the claimed role. Users based their selection on macromorphological features (e.g. colour, texture and location within the soil) and indigenous knowledge. Geophagic materials were mainly sourced from C horizons. They were mostly fine-grained with mica, kaolinite and quartz, and elements such as copper (Cu), zinc (Zn), cobalt (Co) and lead (Pb). Natural pigments, such as iron oxides in highly weathered soils, were recognised as sunscreen materials. Although the mechanisms were not understood by users, laboratory analyses showed that the mineralogical and chemical properties of the soil materials played a crucial role. The sunscreen and healing capabilities of these soils were related to high contents of titanium (TiO2) and iron (Fe2O3) and the presence of kaolinite. Further appraisal of these soil materials is necessary for their conservation and inclusion in land classification. [ABSTRACT FROM AUTHOR]

The global goal to end hunger requires the interpretation of problems and change across multiple domains to create the scope for collaboration, learning, and impactful research. We facilitated a workshop aimed at understanding how stakeholders problematize sustainable diet transition (SDT) among a previously marginalized social group. Using the systems thinking approach, three sub-systems, namely access to dietary diversity, sustainable beneficiation of natural capital, and 'food choice for well-being', highlighted the main forces governing the current context, and future interventions of the project. Moreover, when viewed as co-evolving processes within the multi-level perspective, our identified microlevel leverage points—multi-faceted literacy, youth empowerment, deliberative policymaking, and promotion of sustainable diet aspirations—can be linked and developed through existing national macro-level strategies. Thus, co-designing to problematize transformational SDT, centered on an interdisciplinary outlook and informational governance, could streamline research implementation outcomes to re-structure socio-technical sectors and reconnect people to nature-based solutions. Such legitimate aspirations could be relevant in countries bearing complex socio-political legacies and bridge the local–global goals coherently. This work provides a collaborative framework required to develop impact-driven activities needed to inform evidence-based policies on sustainable diets. [ABSTRACT FROM AUTHOR]

Sub-Saharan Africa faces unprecedented disasters, with climate change expected to exacerbate the frequency and severity of unpredictable and stressful catastrophic events. Unlike developed nations, reconstruction in developing nations is hindered by resource constraints, with certain communities potentially experiencing multiple and enduring effects of disasters. Despite the potential danger of such cumulative community disaster exposure on mental health (e.g. depression), large-scale population-level evidence for the region is limited. We investigated the association between exposure to cumulative disaster and the first onset of depression in a nationally representative survey in South Africa. We used panel data from the South African National Income Dynamics Study (SA-NIDS) from 2008-2017, consisting of 17,255 adult study participants who were depression free at baseline. Risk of first depression onset between individuals exposed and unexposed to community disaster was measured, accounting for multiple disaster exposure over time by fitting generalized estimating equation (GEE) regression models. Data on the geographic location of disasters were obtained from the South African government gazette, and mapped with the government delineated SA-NIDS households' locations. Of the sampled individuals, 2,986 were exposed to disaster during the study duration (17.3%). Increased cumulative community disaster was significantly associated with the likelihood of depression onset (adjusted relative risk [aRR] = 1.20, p<0.01, 95% CI: 1.09-1.33), even after controlling for socio-demographic factors. In sub-group analyses, greater likelihood of depression onset was found among females [but not in men] (aRR = 1.23, p<0.01, 95% CI: 1.09-1.38), Black African [but not in other population group] (aRR = 1.21, p<0.01, 95% CI: 1.09-1.36), lower education attainment group [but not in tertiary and above educational attainment group] (aRR = 1.20, p<0.01, 95% CI: 1.08-1.33), and lower income attainment group [but not in the top income quartile group] (aRR = 1.24, p<0.01, 95% CI: 1.11-1.38), due to cumulative community disaster. Although cumulative community disaster exposure was significantly associated with the first onset of depression, its negative impact may be more pronounced among individuals considered chronically socially vulnerable (i.e. the groups above) in South Africa. Given that many individuals in South Africa rely on social, food parcel relief, and health services from government/public sector, timely access to community-based supportive intervention is needed for disaster survivors, prioritizing socially vulnerable groups to help mitigate problems associated with mental health challenges. [ABSTRACT FROM AUTHOR]

Several neglected and underutilised species (NUS) provide solutions to climate change and creating a Zero Hunger world, the Sustainable Development Goal 2. Several NUS are drought and heat stress-tolerant, making them ideal for improving marginalised cropping systems in drought-prone areas. However, owing to their status as NUS, current crop suitability maps do not include them as part of the crop choices. This study aimed to develop land suitability maps for selected NUS [sorghum, (Sorghum bicolor), cowpea (Vigna unguiculata), amaranth and taro (Colocasia esculenta)] using Analytic Hierarchy Process (AHP) in ArcGIS. Multidisciplinary factors from climatic, soil and landscape, socio-economic and technical indicators overlaid using Weighted Overlay Analysis. Validation was done through field visits, and area under the curve (AUC) was used to measure AHP model performance. The results indicated that sorghum was highly suitable (S1) = 2%, moderately suitable (S2) = 61%, marginally suitable (S3) = 33%, and unsuitable (N1) = 4%, cowpea S1 = 3%, S2 = 56%, S3 = 39%, N1 = 2%, amaranth S1 = 8%, S2 = 81%, S3 = 11%, and taro S1 = 0.4%, S2 = 28%, S3 = 64%, N1 = 7%, of calculated arable land of SA (12 655 859 ha). Overall, the validation showed that the mapping exercises exhibited a high degree of accuracies (i.e. sorghum AUC = 0.87, cowpea AUC = 0.88, amaranth AUC = 0.95 and taro AUC = 0.82). Rainfall was the most critical variable and criteria with the highest impact on land suitability of the NUS. Results of this study suggest that South Africa has a huge potential for NUS production. The maps developed can contribute to evidence-based and site-specific recommendations for NUS and their mainstreaming. Also, the maps can be used to design appropriate production guidelines and to support existing policy frameworks which advocate for sustainable intensification of marginalised cropping systems through increased crop diversity and the use of stress-tolerant food crops. [ABSTRACT FROM AUTHOR]

While food insecurity is a persistent public health challenge, its long-term association with depression at a national level is unknown. We investigated the spatial heterogeneity of food insecurity and its association with depression in South Africa (SA), using nationally-representative panel data from the South African National Income Dynamics Study (years 2008–2015). Geographical clusters ("hotpots") of food insecurity were identified using Kulldorff spatial scan statistic in SaTScan. Regression models were fitted to assess association between residing in food insecure hotspot communities and depression. Surprisingly, we found food insecurity hotspots (p < 0.001) in high-suitability agricultural crop and livestock production areas with reliable rainfall and fertile soils. At baseline (N = 15,630), we found greater likelihood of depression in individuals residing in food insecure hotspot communities [adjusted relative risk (aRR) = 1.13, 95% CI:1.01–1.27] using a generalized linear regression model. When the panel analysis was limited to 8,801 participants who were depression free at baseline, residing in a food insecure hotspot community was significantly associated with higher subsequent incidence of depression (aRR = 1.11, 95% CI:1.01–1.22) using a generalized estimating equation regression model. The association persisted even after controlling for multiple socioeconomic factors and household food insecurity. We identified spatial heterogeneity of food insecurity at a national scale in SA, with a demonstrated greater risk of incident depression in hotspots. More importantly, our finding points to the "Food Security Paradox", food insecurity in areas with high food-producing potential. There is a need for place-based policy interventions that target communities vulnerable to food insecurity, to reduce the burden of depression. [ABSTRACT FROM AUTHOR]

Main conclusion: Bambara groundnut has the potential to be used to contribute more the climate change ready agriculture. The requirement for nitrogen fixing, stress tolerant legumes is clear, particularly in low input agriculture. However, ensuring that existing negative traits are tackled and demand is stimulated through the development of markets and products still represents a challenge to making greater use of this legume. World agriculture is currently based on very limited numbers of crops, representing a significant risk to food supplies, particularly in the face of climate change which is expected to increase the frequency of extreme events. Minor and underutilised crops can help to develop a more resilient and nutritionally dense future agriculture. Bambara groundnut [Vigna subterranea (L.) Verdc.[, as a drought resistant, nitrogen-fixing, legume has a role to play. However, as with most underutilised crops, there are significant gaps in knowledge and also negative traits such as 'hard-to-cook' and 'photoperiod sensitivity to pod filling' associated with the crop which future breeding programmes and processing methods need to tackle, to allow it to make a significant contribution to the well-being of future generations. The current review assesses these factors and also considers what are the next steps towards realising the potential of this crop. [ABSTRACT FROM AUTHOR]

Grain legumes have potential to contribute to food and nutritional security in water-scarce areas. Information on their yield, water use and water productivity (WP) would be useful for their promotion. The aim of the study was to make a comparative assessment of adaptation, yield, water use and WP of an African indigenous grain legume (bambara groundnut) and two major grain legumes (dry bean and groundnut) under rainfed, deficit and optimum irrigation conditions. Field trials were conducted during the 2015/16 and 2016/17 summer seasons in KwaZulu-Natal, South Africa, using a split-plot design arranged in completely randomised blocks with three replications. Data collected included stomatal conductance, leaf area index, timing of key phenological stages and yield. Water use was calculated as a residual of the soil water balance. Water productivity was obtained as the quotient of grain yield and water use. Crops adapted to limited soil water availability through stomatal regulation and reduction in canopy size and duration. Yield, yield components and WP varied significantly (P < 0.05) among crop species. During 2015/16, groundnut had the highest yield and WP (10 540 kg·ha-1 and 0.99 kg·m-3, respectively). During 2016/17, the highest yield and WP were observed in dry bean, 2 911 kg·ha-1 and 0.75 kg·m-3, respectively. For both seasons, dry bean had the lowest water use (143-268 mm) across all water treatments. Dry bean and groundnut out-- performed bambara groundnut with respect to yield, harvest index and WP. For any promotion of bambara groundnut as an alternative crop, there is need for crop improvement to improve yield and WP. [ABSTRACT FROM AUTHOR]

Understanding critical management practices during seed development would help to improved crop production as climate patterns change. This study focused on the interactive effect of soil fertility with harvesting stages, on hybrid maize yield under two different agro-ecological locations during the 2014/2015 and 2015/2016 summer seasons in KwaZulu-Natal, South Africa. The 2015/2016 season was drier than that of 2014/2015. The field trials were split plots design, where varying fertility levels (main plot) and harvesting stages (sub plots) were replicated four times. The interaction was determined by variables of plant growth, physiology and yield parameters. The plant growth and physiological parameters measured were significantly influenced (P < 0.001) by the interaction of fertility levels across days after planting and silking. The interactions of soil fertility levels with harvesting stages had significant effects (P < 0.05) on all yield components during the wetter 2014/2015 season, as well as on seed yield, harvest index, thousand seed weight and total biomass in the drier 2015/2016 season. Optimal fertilization improved maize yield at each stage of harvesting. This study showed that harvesting stress-free optimally-fertilized maize at dent stage maximized yield potential than allowing it to reach physiological maturity under stressful conditions. [ABSTRACT FROM AUTHOR]

Reports of neglected and underutilized crops' (NUS) potential remain mostly anecdotal with limited and often incoherent research available to support them. This has been attributed to lack of clear research goals, limited funding directed at NUS and journal apathy toward publishing work on NUS. The latter points also explain the lack of interest from emerging and established researchers. Additionally, the NUS community's inability to articulate a roadmap for NUS' promotion may have unintentionally contributed to this. The current study is a sequel to an initial study that assessed the status of NUS in South Africa. The objective of this follow-up study was then to (i) identify priority NUS, and (ii) articulate a strategy and actionable recommendations for promoting NUS in South Africa. The study identified 13 priority NUS, categorized into cereals, legumes, root, and tuber crops and leafy vegetables based on drought and heat stress tolerance and nutritional value. It is recommended that the available limited resources should be targeted on improving these priority NUS as they offer the best prospects for success. Focus should be on developing value chains for the priority NUS. This should be underpinned by science to provide evidence-based outcomes. This would assist to attract more funding for NUS research, development and innovation in South Africa. It is envisaged that through this roadmap, NUS could be transformed from the peripheries into mainstream agriculture. This study provides a template for developing a roadmap for promoting NUS that could be transposed and replicated among the 14 other southern African states. [ABSTRACT FROM AUTHOR]

Underutilised crops represent an important component of agro-biodiversity with potential to contribute to climate change adaptation, food security and sovereignty in poor rural areas. However, despite emerging research interest, they continue to occupy the peripheries of mainstream agriculture. There is a need to consolidate the gains made and propose a coherent strategy for translating underutilised crops into mainstream agriculture. The status of underutilised crops in South Africa (past, present and on-going research) was reviewed with a view to identifying existing gaps, opportunities and challenges for developing future research capacity. The review confirmed that several underutilised crops are drought tolerant, adapted to low levels of water use and thus suitable for cultivation in most marginal production areas typical of semi-arid and arid cropping systems. In addition, several are nutrient dense and could be used to improve dietary diversity among poor rural people. These characteristics make them ideal for inclusion in climate change adaptation and promotion of food sovereignty. There is need for a paradigm shift away from practices that have promoted a few major crops to an agro-ecology based land use classification system that recognises diversity and strengthens food networks. There is a need to identify those underutilised crops that show the greatest potential for success and can be fitted into semi-arid and arid cropping systems and prioritise them for future research, development and innovation. [ABSTRACT FROM AUTHOR]

Predicting yield response to water is important in rainfed agriculture. The objective of this study was to calibrate and test AquaCrop for simulating yield of 3 sorghum genotypes (PAN8816, a hybrid; Macia, an open-pollinated variety; and Ujiba, a landrace) grown during the 2013/14 and 2014/15 planting seasons (early, optimal and late planting dates). Variables considered during model evaluation included canopy cover (CC), biomass (B) and yield (Y). The model was able to simulate CC (R² ≥ 0.710; root mean square error (RMSE) ≤ 22.73%; Willmott's d-index (d) ≥ 0.998), biomass accumulation (R² ≥ 0.900; RMSE ≤ 10.45%; d ≥ 0.850), harvest index (R² ≥ 0.902; RMSE ≤ 7.17%; d ≥ 0.987) and yield (R² ≥ 0.945; RMSE ≤ 3.53%; d ≥ 0.783) well for all genotypes and planting dates after calibration. AquaCrop over-estimated biomass and crop yield. The relatively good simulations produced by the minimum data input calibration confirm AquaCrop's simplicity and suitability for use in places where extensive datasets may be unavailable. Biomass and yield overestimation resulting from the use of the minimum data input calibration suggests that other parameters (water productivity, canopy sensitivity to water stress and water stress coefficient) are required to improve canopy and yield predictions for sorghum genotypes. [ABSTRACT FROM AUTHOR]

It is vital to understand how rainfall onset, amount and distribution between planting dates affect sorghum yield and water use, in order to aid planting date and cultivar selection. This study investigated morphological, physiological, phenological, yield and water use characteristics of different sorghum genotypes in response to different planting dates under rainfed conditions. Four genotypes (PAN8816 [hybrid], Macia [open-pollinated variety, OPV], Ujiba and IsiZulu [both landraces]) were planted on 3 planting dates (early, optimal, and late) in a split-plot design, with planting dates as the main factor. Low soil water at the optimal planting date was associated with delayed crop establishment and low final emergence. Sorghum genotypes adapted to low and irregular rainfall at the late planting date through low leaf number, canopy cover, chlorophyll content index and stomatal conductance, and hastened phenological development. This resulted in low biomass and grain yields. Landraces exhibited grain yield stability across planting dates, whilst OPV and hybrid genotypes significantly reduced grain yield in response to low water availability when planted late. Biomass and grain yield water use efficiency (WUE) were highest at optimal planting date (30.5 and 9.2 kg·ha-1·mm-1), relative to late (23.1 and 8.7 kg·ha-1·mm-1), and early planting dates (25.2 and 8.3 kg·ha-1·mm-1). For PAN8816 and Macia, biomass and grain WUE decreased in response to low soil water content, and irregular and disproportionate rainfall experienced during the late planting date. By contrast, biomass and grain WUE for Ujiba and IsiZulu improved with decreasing rainfall. PAN8816 is recommended when planting under low soil water availability to maximize crop stand. Cultivation of Macia is recommended under optimal conditions. Ujiba and IsiZulu landraces are recommended for low rainfall areas with highly variable rainfall. Repetition or modelling of genotype responses across environments different from Ukulinga is required for thorough water use characterisation of these genotypes. [ABSTRACT FROM AUTHOR]

Approximately 70% of the population in the semi- and arid tropics reside in rural areas and depend on agriculture for their livelihood. Crop production is primarily focused on a few starchy staple crops. While this can ensure adequate calories, it inadvertently neglects the need for dietary diversity. Consequently, food and nutritional insecurity remains prevalent in the semi- and arid tropics. We reviewed the legume value chain with the aim to identify opportunities and challenges to unlocking their value and promoting them in the tropics. Several grain legumes are rich in proteins and micronutrients. They also possess adaptability to marginal environmental conditions such as drought and low input systems which typify rural landscapes. Adaptability to abiotic stresses such as drought makes them key to agriculture in areas that will receive less rainfall in the future. However, this potential was currently not being realized due to a range of challenges. Aspects related to their seed systems, production, post-harvest handling and marketing remain relatively under-researched. This was especially true for minor legumes. There is a need for trans-disciplinary research which will address the entire value chain, as has been done for major starchy crops. This could also unlock significant economic opportunities for marginalized groups such as women. This will unlock their value and allow them to contribute meaningfully to food and nutrition security as well as sustainable and resilient cropping systems. [ABSTRACT FROM AUTHOR]

The Southern African Development Community's (SADC) water and energy sectors are under increasing pressure due to population growth and agricultural and industrial development. Climate change is also negatively impacting on the region's water and energy resources. As the majority of SADC's population lives in poverty, regional development and integration are underpinned by water and energy security as the watercourses in the region are transboundary in nature. This paper reviews the region's water and energy resources and recommends policies based on the water-energy nexus approach. This is achieved by reviewing literature on water and energy resources as well as policy issues. Water resources governance provides a strong case to create a waterenergy nexus platform to support regional planning and integration as SADC countries share similar climatic and hydrological conditions. However, there has been a gap between water and energy sector planning in terms of policy alignment and technical convergence. These challenges hinder national policies on delivering economic and social development goals, as well as constraining the regional goal of greater integration. Regional objectives on sustainable energy and access to clean water for all can only be achieved through the recognition of the water-energy nexus, championed in an integrated and sustainable manner. A coordinated regional water-energy nexus approach stimulates economic growth, alleviates poverty and reduces high unemployment rates. The shared nature of water and energy resources requires far more transboundary water-energy nexus studies to be done in the context of regional integration and policy formulation. [ABSTRACT FROM AUTHOR]

Three sweet potato cultivars (A40, A45 and 199062.1) were planted in three small-scale farms located under different agro-ecological zones of KwaZulu-Natal. The objective was to assess growth, physiological responses and yield of the sweet potato cultivars under low-input agricultural system and different environmental conditions. Sweet potato planted at Richards Bay (28°19'S; 32°06E), a coastal sandy soil location, recorded low stomatal conductance(SC; 102.2 m moles m−2s−1) and chlorophyll content index (CCI; 29.4). This consequently resulted in reduced vine length, leaf number and branching of sweet potato plants. Environmental conditions in that location (Richards Bay) such as high evapotranspiration, high temperatures and low water retention capacity of sandy soils created drought stress condition. This caused reduction in photosynthetic activities and translocation to the harvestable plant parts. The other two locations (Deepdale at 28°01'S; 28°99'E and Umbumbulu at 29°98'S; 30°70'E) located further from the coast and characterized by clayey soils recorded higher SC and CCI. Branching and number of leaves were significantly influenced by locations and growing season while vine length varied with locations, indicating specific varietal adaptation. Biomass and storage root yield followed a similar trend as plant growth and physiology. Richards Bay recorded very low biomass and storage root yield (5.4 and 5.0 t ha−1) in both seasons while Deepdale recorded higher yields (42.0 t ha−1) during the first growing season. Yields reduced by 67% (13.6 t ha−1) in the second season. Storage root yields from Umbumbulu were stable in both growing seasons (29.4 and 28 t ha−1during seasons one and two, respectively). Adding fertilizer only improved storage roots yield in Richards Bay, otherwise cultural practises were responsible for storage root yield increases in Deepdale and Umbumbulu. Orange-fleshed sweet potato cultivar A45 showed good environmental plasticity while cultivar 199062.1 responded well to fertilizer application. This indicated its suitability for use in food security programmes under low-input agriculture. [ABSTRACT FROM PUBLISHER]

Bottle gourd [Lagenaria siceraria(Molina) Standly] is a neglected underutilized species that is available only as a landrace in sub-Saharan Africa. The objective of this study was to evaluate responses of bottle gourd landraces to water stress compared with pumpkin (Cucurbita maxima) and cucumber (Cucurbita pepo), the closest relatives. For this purpose, two bottle gourd landraces and one green pumpkin cultivar and a cucumber cultivar were grown under controlled conditions at three levels of water stress. Landraces had longer vines than hybrids while hybrid varieties produced more leaves than landraces at all levels of water treatments. The responses of landraces and hybrids to water stress were similar in that they all showed lower chlorophyll content index, stomatal conductance and plant growth in response to decreasing water availability. However, the landraces showed better stomatal regulation indicating better acclimation to water stress. The comparable performance of landraces to the exotic pumpkin and cucumber varieties and their water stress tolerance suggests that bottle gourd could be promoted as an alternative food security crop in rural communities. [ABSTRACT FROM PUBLISHER]

The aim of this study was to parameterize and test the generic crop model AquaCrop for a local bambara groundnut [Vigna subterranea (L.) Verdc] landrace. Such a model should be water driven and assist in the promotion of neglected and underutilized species as possible future crops under water-limited conditions. AquaCrop was parameterized for a South African bambara groundnut landrace using data from controlled field and rain shelter experiments conducted during two seasons (2010/2011 and 2011/2012) at Pretoria, South Africa. Observed weather, soil physical, and measured crop parameters from optimum experiments conducted during 2010/2011 were used to develop respective climate, soil, and crop files in AquaCrop and to parameterize the model. Model parameterization for bambara groundnut showed a very good fit for canopy cover (R² = 0.94, Willmott's d index of agreement = 0.99, RMSE = 3.37%) and biomass (R² = 0.96, d index = 0.99, RMSE = 1.29 Mg ha-1). The model also predicted final biomass (RMSE = 1.70 Mg ha-1) and yield (RMSE = 0.29 Mg ha-1) reasonably well. Model testing showed good fit for canopy cover under irrigated (R² = 0.86, d index = 0.96, RMSE = 9.72%) and rainfed field conditions (R² = 0.95, d index = 0.97, RMSE = 6.18%) compared with simulation of results from rain shelter experiments. The model simulated final biomass and yield of bambara groundnut very well under field conditions. The model's performance under rainfed conditions make it particularly suited for extrapolation to marginal areas of agricultural production in South Africa and the region. [ABSTRACT FROM AUTHOR]

Seed development and germination are two distinct physiological stages that are normally separated by a metabolically quiescent period in orthodox seeds. Comparison of seed water status during these two processes and how it influences the biochemical activities remains unclear. The objective of this study was to compare soybean (Glycine max (L.) Merrill cv. Ohio FG1) seed development and germination, including the first 6 h after radicle protrusion, with respect to soluble carbohydrate occurrence at different stages characterized by water content and osmolality. Cyclitols and sugars were monitored at nine stages of development and during the first 30 h of germination. Three phases of water loss and osmolality increase found during seed development were correlated with three phases of water absorption and osmolality decrease during seed germination. This study provided evidence that soybean seed cotyledons and axes have similar patterns of water content and osmolality during seed development and germination and that three major events of soluble carbohydrate occurrence are shared by soybean seed parts during development and germination.Key words: seed development, seed germination, soluble carbohydrates, soybean, water status.Le développement de la graine et sa germination constituent deux stades physiologiques distincts qui sont normalement et très généralement séparés par une période de quiescence métabolique. La comparaison de l'état d'hydratation au cours de ces deux processus, et la façon selon laquelle il influence les activités biochimiques demeure obscure. L'objectif de l'étude était de comparer le développement et la germination de la graine de la fève soja (Glycine max (L.) Merrill cv. Ohio FG1), incluant les 6 premières h après l'émergence de la radicule, en observant l'apparition de glucides solubles à différents stades caractérisés par la teneur en eau et l'osmolalité. Les auteurs ont suivi les cyclitols et les sucres à 9 stades du développement et au cours des 30 premières h de la germination. Trois phases de perte en eau et d'augmentation de l'osmolalité au cours du développement de la graine concordent avec trois phases d'absorption d'eau et d'augmentation d'osmolalité au cours de la germination de la graine. Cette étude fournit la preuve que la tigelle et les cotylédons de la fève soja ont des patrons de teneur en eau et d'osmolalité similaires au cours du développement et de la germination de la graine, et que trois événements majeurs dans la formation des glucides solubles sont communs aux organes de la graine au cours du développement et de la germination.Mots clés : développement de la graine, germination de la graine, glucides solubles, fève soja, état hydrique.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Reference 1 Mugiyo H, Chimonyo VGP, Sibanda M, Kunz R, Nhamo L, Masemola CR, et al. (2021) Multi-criteria suitability analysis for neglected and underutilised crop species in South Africa. There is an error in the seventh author's name. [Extracted from the article]

Achieving sustainable socio-economic development requires approaches that enhance resource use efficiencies and can address current cross-sectoral challenges in an integrated manner. Existing evidence suggests an urgent need for polycentric and transformative approaches, as global and local systems have come under strain. This study conducted a systematic literature review at the global level to assess the progress made towards achieving a circular economy between 2010 and 2020, a period covering the formulation of the Sustainable Development Goals (SDGs) and the initial five years of their implementation. The focus was on the potential of improved water and energy use efficiency, linking them to food production within the context of a circular economy. Identifying successes, opportunities, challenges, and pathways towards a circular economy from the literature review facilitated developing a conceptual framework to guide strategic policy formulations towards a more sustainable economy. A combination of transformative approaches is analysed in an integrated way in response to the 2030 global agenda on sustainable development. Thus, the study is informed by the initiatives to attain SDGs and mitigating negative environmental impacts due to waste and pollution. The premise is to enhance transformational change as a catalyst for employment creation and the attainment of a green economy while reducing waste. Transformative approaches have been identified to provide pathways towards global climate targets and protection of the environment from further degradation. They are a catalyst to achieve SDG 12 on ensuring sustainable consumption and production patterns. [ABSTRACT FROM AUTHOR]

Sustainable Development Goals (SDGs) acknowledge the inter-linkages between human wellbeing, economic prosperity, and a healthy environment and, hence, are associated with a wide range of topical issues that include the securities of water, energy and food resources, poverty eradication, economic development, climate change, health, among others. As SDGs are assessed through targets to be achieved by 2030 and monitored through measurable indicators, this study applied the nexus planning model to monitor and evaluate progress towards SDGs using South Africa as a case study. The study highlighted pathways to ensure socio-ecological sustainability and environmental health by establishing the connectivity between SDGs and nexus approaches. The linkages between SDGs and nexus planning facilitated the sustainable management of resources in an integrated manner. They addressed the cross-sectoral synergies, value-addition, and trade-offs within interlinked sectors. The connectedness of current challenges facing humankind (climate change, rapid urbanisation, migration, and the emergence of novel infectious diseases) require transformative approaches that address these cross-cutting challenges holistically. Managing the intricate relationships between distinct but interconnected sectors through nexus planning has provided decision support tools to formulate coherent strategies that drive resilience and sustainability. The established linkages between nexus planning and SDGs have strengthened cross-sectoral collaboration and unpacked measures for cooperative governance and management through evidence-based interventions. As food production, water provision, and energy accessibility are the major socio-economic and environmental issues currently attracting global attention; the methodology promotes attaining sustainability by 2030. [ABSTRACT FROM AUTHOR]

Sweet sorghum (Sorghum bicolor L. Moench) is highly susceptible to weed competition during the early growth stages; hence, intercropping is considered to overcome the weed competition challenge. This study was conducted to determine the performance of sweet sorghum in legume intercropping systems under different weed management pressures. Three cropping systems (sole crop, inter-row, and intra-row intercropping) and three weed management levels (no weeding after crop emergency, ceasing weeding 50 days after crop emergency, and weeding throughout) were tested. Intercropping pattern had a significant (p < 0.05) impact on the plant and the number of leaves per plant, while other treatments remained insignificant during the 2017/18 growing season. During the 2018/19 growing season, the intercropping pattern had a significant (p < 0.05) effect on dry and fresh biomass and plant height at 60 days after emergence. An increase in weeding frequencies reduced Brix (◦Bx). Uncontrolled weed plots had the lowest sweet sorghum dry biomass accumulation, whereas the biomass increased as weeding frequencies increased but remained insignificant as weeding frequencies further increased from 50% to 100% in both seasons. Consequently, SS/DB intra-row intercropping and intermediate weeding are sufficient for optimum SS biomass production and sugar levels. [ABSTRACT FROM AUTHOR]

The economic potential of African leafy vegetables (ALVs) remains obscured by a poorly developed value chain. This scoping review assembled and examined scattered knowledge generated on ALVs across southern Africa, focusing on production, processing, marketing, and consumption. Two electronic databases (Scopus and Web of Science) were screened, and a total of 71 relevant studies were included and evaluated. The review provides a state of the art on knowledge related to utilisation of ALVs across the entire value chain. The findings show that functional properties are of prime importance in the production and consumption of ALVs. However, the lack of improved germplasm and a non-existent seed supply system are significant production bottlenecks. Pests and diseases affecting the productivity of ALVs remain mostly unexplored. Sun-drying and boiling were the most reported post-harvest processing methods, suggesting that traditional processing methods are still prominent. Many studies also confirmed the predominance of informal markets in the trading of ALVs as they fail to penetrate formal markets because of poor product positioning and exclusion from produce demand and supply forecasts. The inception of cultivar development, mechanised processing methods, and market linkages will enhance the profitability of ALVs in the region. This review enhances the gaining of insight into the state of different value chain components will assist in upscaling production, value addition of products, and enhance marketing efficiency. There is a great opportunity for basic and applied research into ALVs. [ABSTRACT FROM AUTHOR]

Lack of cereal nutritional water productivity (NWP) information disadvantages linkages of nutrition to water–food nexus as staple food crops in Sub-Saharan Africa (SSA). This study determined the suitability of sorghum (Sorghum bicolor L. Moench) genotypes to alleviate protein, Zn and Fe deficiency under water-scarce dryland conditions through evaluation of NWP. Sorghum genotypes (Macia, Ujiba, PAN8816, IsiZulu) NWP was quantified from three planting seasons for various sorghum seed nutrients under dryland semi-arid conditions. Seasons by genotypes interaction highly and significantly affected NWPStarch, Ca, Cu, Fe, and significantly affected NWPMg, K, Na, P, Zn. Genotypic variations highly and significantly affected sorghum NWPProtein, Mn. Macia exhibited statistically superior NWPprotein (13.2–14.6 kg·m−3) and NWPZn (2.0–2.6 g·m−3) compared to other tested genotypes, while Macia NWPFe (2.6–2.7 g·m−3) was considerably inferior to that of Ujiba and IsiZulu landraces under increased water scarcity. Excellent overall NWPprotein, Fe and Zn under water scarcity make Macia a well-rounded genotype suitable to alleviating food and nutritional insecurity challenges in semi-arid SSA; however, landraces are viable alternatives with limited NWPprotein and Zn penalty under water-limited conditions. These results underline genotype selection as a vital tool in improving "nutrition per drop" in semi-arid regions. [ABSTRACT FROM AUTHOR]

In many poorer parts of the world, biofortification is a strategy that increases the concentration of target nutrients in staple food crops, mainly by genetic manipulation, to alleviate prevalent nutrient deficiencies. We reviewed the (i) prevalence of vitamin A, iron (Fe) and zinc (Zn) deficiencies; (ii) availability of vitamin A, iron and Zn biofortified crops, and their acceptability in South Africa. The incidence of vitamin A and iron deficiency among children below five years old is 43.6% and 11%, respectively, while the risk of Zn deficiency is 45.3% among children aged 1 to 9 years. Despite several strategies being implemented to address the problem, including supplementation and commercial fortification, the prevalence of micronutrient deficiencies is still high. Biofortification has resulted in the large-scale availability of βcarotene-rich orange-fleshed sweet potatoes (OFSP), while provitamin A biofortified maize and Zn and/or iron biofortified common beans are at development stages. Agronomic biofortification is being investigated to enhance yields and concentrations of target nutrients in crops grown in agriculturally marginal environments. The consumer acceptability of OFSP and provitamin A biofortified maize were higher among children compared to adults. Accelerating the development of other biofortified staple crops to increase their availability, especially to the target population groups, is essential. Nutrition education should be integrated with community health programmes to improve the consumption of the biofortified crops, coupled with further research to develop suitable recipes/formulations for biofortified foods. [ABSTRACT FROM AUTHOR]

Increasing agricultural productivity has always been a prominent feature on the regional agenda due to a high incidence of food and nutrition insecurity. This review assessed the current status of irrigated agriculture in southern Africa from a water–energy–food (WEF) nexus perspective. Gaps and opportunities for improving irrigated agriculture within the context of the WEF nexus were also assessed in terms of the feasible limits to which they can be exploited. Southern Africa faces water scarcity, and climate projections show that member states will face increased physical and/or economic water scarcity by as early as 2025, which will have negative impacts on water, energy and food production. Recurrent droughts experienced across the region reaffirm the sensitive issues of food and energy insecurity as well as water scarcity. Projections of an increasing population within the region indicate increased water, energy and food demand. With agriculture already accounting for about 70% of water withdrawals, increasing the area under irrigation will place additional demand on already strained energy grids and scarce water resources. This poses the question—is increasing irrigated agriculture a solution to improving water access, food security and energy supply? While there are prospects for increasing the area under irrigation and subsequent improvement in agricultural productivity, adopting a WEF nexus approach in doing so would mitigate trade-offs and unintended consequences. Consideration of the WEF nexus in integrated resources planning and management eliminates the possibilities of transferring problems from one sector to other, as it manages synergies and trade-offs. While it is acknowledged that improving water productivity in irrigated agriculture could reduce water and energy use while increasing yield output, there is a need to decide how such savings would then be reallocated. Any intervention to increase the irrigated area should be done in the context of a WEF nexus analytical framework to guide policy and decision-making. Technical planning should evolve around the WEF nexus approach in setting targets, as WEF nexus indicators would reveal the performance and impact of proposed interventions on any of the three WEF nexus components. [ABSTRACT FROM AUTHOR]