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Bambara groundnut (Vigna subterranean L. Verdc) is grown by smallholders and subsistence farmers in the marginal parts of sub-Saharan Africa. This legume is native to Africa and is cultivated throughout semi-arid sub-Saharan Africa. It is hardy and has been recognized as a nutritious food source in times of scarcity. Drought can negatively affect the germination or establishment of seedlings in the early stages of crop growth. Drought can limit the growing season of certain crops and create conditions that encourage the invasion of insects and diseases. Drought can also lead to a lack of crop yield, leading to rising food prices, shortages, and possibly malnutrition in vulnerable populations. A drought-tolerant genotype can be identified at the germination stage of Bambara groundnut by screening for drought-tolerance traits, and this knowledge can be applied to Bambara crop improvement programs to identify drought-tolerant traits during early growth phases. As an osmolyte, polyethylene glycol (PEG 6000) reduced water potential and simulated drought stress in Bambara groundnut seeds of different genotypes. Osmolytes are low-molecular-weight organic compounds that influence biological fluid properties. In this study, 24 Bambara groundnut genotypes were used. Data were collected on seed germination percentage (G%), germination velocity index (GVI), mean germination time (MGT), root dry mass (RDM), root fresh mass (RFM), and seven drought tolerance indices: mean productivity (MP), tolerance index (TOL), geometric mean productivity (GMP), stress susceptibility index (SSI), yield index (YI), yield stability index (YSI), stress tolerance index (STI) as well as seed coat color measurements. The data were applied to the mean observation of genotypes under simulated drought conditions (Ys) and the mean observation of genotypes under controlled conditions (Yp). Germination%, germination velocity index (GVI), mass germination time (MGT), and root fresh mass (RFM) differed significantly (p < 0.001) between the two stress conditions. Bambara genotypes Acc 82 and Acc 96 were found to be the most drought-tolerant. [ABSTRACT FROM AUTHOR]

Cowpea (Vigna unguiculata (L.) Walp) is an important legume crop with immense potential for nutritional and food security, income generation, and livestock feed in Sub-Saharan Africa. The crop is highly tolerant to heat and drought stresses which makes it an extremely important crop for improving resilience in crop production in the face of climate change. This study was carried out to assess the genetic diversity and population structure of 90 cowpea accessions using single nucleotide polymorphism (SNP) markers. Out of 11,940 SNPs used, 5864 SNPs were polymorphic and maintained for genome diversity analysis. Polymorphic information content (PIC) values ranged from 0.22 to 0.32 with a mean value of 0.27. The model-based Bayesian STRUCTURE analysis classified 90 cowpea accessions into four subpopulations at K = 4, while the distance-based cluster analysis grouped the accessions into three distinct clusters. The analysis of molecular variance (AMOVA) revealed that 59% and 69% of the total molecular variation was attributed to among individual variation for model-based and distance-based populations, respectively, and 18% was attributed to within individual variations. Furthermore, the low heterozygosity among cowpea accessions and the high inbreeding coefficient observed in this study suggests that the accessions reached an acceptable level of homozygosity. This study would serve as a reference for future selection and breeding programs of cowpea with desirable traits and systematic conservation of these plant genetic resources. [ABSTRACT FROM AUTHOR]

Currently, the world population is increasing, and humanity is facing food and nutritional scarcity. Climate change and variability are a major threat to global food and nutritional security, reducing crop productivity in the tropical and subtropical regions of the globe. Cowpea has the potential to make a significant contribution to global food and nutritional security. In addition, it can be part of a sustainable food system, being a genetic resource for future crop improvement, contributing to resilience and improving agricultural sustainability under climate change conditions. In malnutrition prone regions of sub-Saharan Africa (SSA) countries, cowpea has become a strategic dryland legume crop for addressing food insecurity and malnutrition. Therefore, this review aims to assess the contribution of cowpea to SSA countries as a climate-resilient crop and the existing production challenges and perspectives. Cowpea leaves and immature pods are rich in diverse nutrients, with high levels of protein, vitamins, macro and micronutrients, minerals, fiber, and carbohydrates compared to its grain. In addition, cowpea is truly a multifunctional crop for maintaining good health and for reducing non-communicable human diseases. However, as a leafy vegetable, cowpea has not been researched and promoted sufficiently because it has not been promoted as a food security crop due to its low yield potential, susceptibility to biotic and abiotic stresses, quality assurance issues, policy regulation, and cultural beliefs (it is considered a livestock feed). The development of superior cowpea as a leafy vegetable can be approached in different ways, such as conventional breeding and gene stacking, speed breeding, mutation breeding, space breeding, demand-led breeding, a pan-omics approach, and local government policies. The successful breeding of cowpea genotypes that are high-yielding with a good nutritional value as well as having resistance to biotics and tolerant to abiotic stress could also be used to address food security and malnutrition-related challenges in sub-Saharan Africa. [ABSTRACT FROM AUTHOR]

Cowpea (Vigna unguiculata L. Walp.) is a drought-tolerant legume crop widely cultivated in arid and semi-arid regions of sub-Saharan Africa (SSA), including South Africa. The leaves, young and immature pods, and grains of cowpea are a vital source of plant-based proteins and essential nutrients for human wellbeing. The objective of this study was to determine the effect of genotype-by-environment interaction (GEI) on the contents of micro-nutrients and protein content of the green pods of cowpea to recommend superior genotypes for cultivation and breeding. Fifteen genetically diverse cowpea genotypes were evaluated across six test environments in South Africa, using a randomized complete block design replicated three times. Micro-nutrients such as iron (Fe), manganese (Mn), zinc (Zn), and total protein (TP) content were determined in the immature pods of cowpea. Data were subjected to additive main effects and multiplicative interaction (AMMI) analysis. Significant (p < 0.05) genotype (G) differences were detected for Fe, Mn, Zn and TP, suggesting the presence of genetic divergence for selection. Furthermore, a significant (p < 0.05) environment (E) effect was recorded for all studied nutrient, indicating the impact of the test environments on nutrient compositions. The GEI effect was significant for all the assessed nutrients, indicating that specific and broadly adapted genotypes could be identified. Based on best linear unbiased estimates (BLUEs) and best linear unbiased predictors (BLUPs) analyses, the following ranges of nutrient compositions were observed: Fe (83.70–109.03 and 69.77–134.16 mg/kg), Mn (20.60–33.83 and 18.75–36.83 mg/kg), Zn (33.79–40.53 and 28.81 mg/kg), and TP (22.37–24.54 and 21.44–25.25 mg/kg), respectively, across the tested environments. The AMMI test procedure (FR-test) identified the first interaction principal component axis (IPCA-1) to be a significant (p < 0.05) component of the GEI, explaining >91% of phenotypic variation in nutrient contents among the tested genotypes across environments. Cowpea genotypes Meterlong Bean and TVU-14196 were identified for their high Fe, Zn and Mn contents and recommended for cultivation in Mafikeng, Potchefstroom and Roodeplaat in South Africa. For TP, genotypes Meterlong Bean and Kisumu Mix had stable performance and are recommended for production at all the test environments. The identified genotypes are recommended for future cultivation and breeding to supplement micro-nutrients and protein and combat nutrient deficiencies and malnutrition in South Africa. [ABSTRACT FROM AUTHOR]

Bambara groundnut (Vigna subterranea [L.] Verdc.) is a nutritionally rich grain legume crop indigenous to Africa. It is tolerant to drought stress and has become adapted to grow under low input and marginal agricultural production systems in Africa and Asia. Bambara groundnut is an orphan crop, and represents a neglected and under researched plant genetic resource. Modern crop management, production technologies, and value chains are yet to be developed in Africa to achieve the potential economic gains from Bambara groundnut production and marketing. In sub-Saharan Africa (SSA) the production and productivity of Bambara groundnut is low and stagnant because of diverse abiotic and biotic stresses and socio-economic constraints. Improved crop management and post handling technologies, modern varieties with high yield and nutritional quality, value addition, and market access are among the key considerations in current and future Bambara groundnut research and development programs. This paper presents progress on Bambara groundnut production, utilization, and genetic improvement in SSA. It presents the key production constraints, genetic resources and analysis, breeding methods and genetic gains on yield, and nutritional quality and outlook. The information presented will guide the sustainable production and effective breeding of the crop in order to pursue food and nutrition security, and improve livelihoods through Bambara groundnut enterprises. [ABSTRACT FROM AUTHOR]