Use of weeds as traditional vegetables in Shurugwi District, Zimbabwe

Research on Moringa (Moringa oleifera Lam.) in Africa

While Moringa oleifera Lam. is gaining importance in Africa, especially sub-Saharan Africa, it is unclear whether research is following the quick pace of its development on the continent. Therefore, this article analyzes the landscape of research dealing with moringa in Africa. This systematic review draws upon 299 eligible articles identified through a search carried out on the Web of Science in April 2023. Research on M. oleifera is rather recent in Africa but interest is increasing among scholars. While the research field is multidisciplinary and cross-sectoral, the literature seems to focus on biological and environmental sciences. Moreover, research is performed mainly in South Africa, Nigeria, Egypt, and Ghana. The analysis suggests a significant potential contribution of moringa to food security and nutrition, climate change mitigation/adaptation, farming systems resilience, and livelihoods. Its versatility and diverse applications and uses make moringa particularly interesting for developing countries, such as African ones. However, this review also underscores some factors hindering its development. Therefore, there is a need to strengthen research on moringa to unlock its potential in Africa. Investments in research, innovation, and development can help address the many challenges that Africa faces and contribute to the transition towards sustainable and resilient food systems.

Corchorus tridens L.: A Review of Its Botany, Phytochemistry, Nutritional Content and Pharmacological Properties

Phytotherapy is a cost-effective alternative that continues to evolve. This has sparked significant research interest in naturally occurring compounds found in edible plants that possess antibacterial, antioxidant, and anticancer properties. Corchorus tridens L. is a wild edible plant widely recognised for its edible leaves, which are used for vegetable and animal feed. The plant is widely distributed across the African continent and is utilised in numerous countries for treating fever, pain, inflammation, and sexually transmitted diseases. Extracts from various parts of this plant exhibit antimicrobial, antioxidant, and pesticidal properties. This plant is a rich source of amino acids, vitamins, essential fatty acids, proteins, and minerals, as well as secondary metabolites such as alkaloids, flavonoids, quinines, steroids, terpenoids, phenols, and tannins. Additional studies are still needed to determine other biological activities, such as anti-inflammatory activity, involvement in the treatment of measles, prevention of anaemia, and pain-relieving properties. The current review aims to provide information on the characteristics, distribution, nutritional content, bioactive compounds, traditional uses, and biological activities of the edible plant species C. tridens L. to stimulate further research interest to address the existing literature gaps concerning this plant.

Urban gardening and neglected and underutilized species in Salvador, Bahia, Brazil

BACKGROUND

Urban agriculture has been evidenced as a food production and environmental sustainability strategy, although it faces many obstacles in Latin American countries. Additionally, in urban areas, low consumption of fruit and greenery is noticeable, along with loss in food diversity, including the neglected and underutilized species (NUS), which involve potential to strengthen local food systems. For this reason, this work has sought to map urban gardens in the city of Salvador, Bahia, Brazil, characterizing their gardeners, and to systematize information regarding food produced and the use of NUS.

METHODS

The municipality's urban gardens were mapped and data was collected from the gardeners. The study included two steps: (i) garden localization; (ii) on-site visits for interviews with gardeners and verification of cultivated food, destination of production, availability, and use of NUS.

RESULTS

Eighteen active food gardens were located, seventeen of which participated in the study: eight (8) communal (UCG) and nine (9) private (UPG). Respondents were on average 55.76 years old, mostly (52.9%) male, working at UPG (88.9%). Women predominated in the UCG (87.5%), with higher levels of education. For 52.9% of the interviewees, the garden was their main source of income. Food produced at the urban gardens was consumed by 82.4% of the gardeners and their families. In 70.6% of the gardens, production was also sold, while 47.1% donated. During the survey, 59 NUS were found and 76.5% of respondents reported consuming 19 of the species. NUS leaves, fruits, and seeds were found to be eaten raw, boiled, or sautéed in various preparations, especially Coleus amboinicus Lour. (76.5%), Eryngium foetidum L. (35.3%), Talinum fruticosum (L.) Juss., and Pereskia aculeata Mill (both 29.4%). Occurrence and utilization of NUS did not present significant associations with the gardens or gardeners (p > 0.05).

CONCLUSIONS

Salvador urban gardens, even in small numbers and without government support, have produced affordable food for the local population, preserved food diversity, and the tradition of NUS cultivation and use. Thus, urban gardens are reaffirmed as relevant spaces that should be included in public policies in order to promote food and nutritional security, biodiversity, and urban environmental sustainability.

Harnessing Opportunities Provided by the Invasive Chromolaena odorata to Keep It under Control

Invasive alien plants (IAPs) have been well-documented as socio-ecological change drivers in most countries globally. Billions of dollars have been spent worldwide on IAP management projects with varying degrees of success. Understanding the contribution of IAPs to human well-being and livelihoods could provide insights into potential sustainable incentives that could be used to achieve effective IAP management. A review was conducted to assess the benefits of the invasive Chromolaena odorata on human well-being and livelihoods. Literature was gathered using keyword searches in electronic databases. The findings from this review showed that C. odorata is utilised in bioenergy production, crop production and protection, ethnopharmacology, human nutrition, and livestock production. However, most of these benefits were reported on the Asian/West African biotype. There was only one ethnopharmacological benefit record on the southern African biotype. This shows that, although C. odorata has significant negative impacts on the environment and livelihoods, its benefits have been integrated into human well-being and livelihoods. Therefore, C. odorata utilisation in bioenergy production, crop and livestock production, crop protection, and ethnopharmacology could create an economic incentive for species control in invaded sites. However, for utilisation to be effective, it should be used as a complementary control strategy.

Leveraging Traditional Ecological Knowledge and Access to Nutrient-Rich Indigenous Foods to Help Achieve SDG 2: An Analysis of the Indigenous Foods of Sauria Paharias, a Vulnerable Tribal Community in Jharkhand, India

Indigenous food systems of traditional communities are potentially sustainable, have nutrient rich food sources and can enhance dietary diversity. Sauria Paharias, are one of the particularly vulnerable tribal groups of Jharkhand India, who despite residing in rich biodiverse environment and possessing traditional ecological knowledge, lag behind various health, and nutritional indicators. Our study explored their traditional ecological knowledge around indigenous foods (IFs), their routine consumption, access, and nutritive values. A cross-sectional mixed methods study was carried out in 18 villages of Godda district, Jharkhand. Free list of all IFs known to the community was developed using focus group discussions. This was followed by enumerating commonly consumed as well as little or historically used IFs. Following the taxonomic classification of these foods, their nutritive values were searched in literature or food samples were analyzed in accredited laboratories. Reasons for consumption and non-consumption of specific IFs were explored. The community was aware of a large number of IFs (n = 193) but only 50% of these were routinely consumed. Rest were either little used or historically consumed. About 47.6% IFs (n = 92) were identified using taxonomic classification; of which 87 IFs were classified based on their common names in secondary literature and five food items were collected, herbariums were prepared and identified. Nutritive values were documented for 84 IFs (this included both routinely consumed as well as little used); out of which 55 foods were found to have nutritive values in existing literature and 29 foods were analyzed in laboratory. Many of these IFs were rich in micronutrients like calcium, iron, zinc, folic acid, vitamin A, and vitamin C. Common reasons for preferences or non-consumption of specific IFs included taste, availability, access seasonality, opportunity cost of access and processing time. Promoting adequate intake of commonly accessed nutrient rich IFs and revival of little used IFs while addressing the causes of non-consumption and mainstreaming them into the daily diets could be an effective strategy to increase the intake of micronutrients. Policies focusing on incorporation of nutrient rich IFs into dietary diversification strategies and ongoing supplementary feeding programs can help address malnutrition in the community.

The Availability of Non-Timber Forest Products under Forest Succession on Abandoned Fields along the Wild Coast, South Africa

Large swathes of arable fields have been abandoned in many areas of the world over the last few decades driven by a multitude of local and broader-scale factors. Many former fields experience a change in vegetation composition and structure post-abandonment, typically through a process of plant succession. The changes in species and abundance mean that the nature and quantity of ecosystem services provided by the former fields also varies. We examined the types of provisioning services obtained from non-timber forest products (NTFPs) with increasing age since field abandonment. We sampled 43 former fields ranging in age since abandonment from approximately 7 to 55 years, and seven plots in intact forests. We held seven focus group discussions with local residents to determine uses of species found in the former fields. Plant cover and species richness increased with former field age, although old field community composition was also influenced by soil chemistry. Of the 177 species recorded, 70 (40%) had one or more uses, spanning six NTFP categories namely, food, building, medicinal, craft, cultural and energy. The number of NTFP species increased with increasing age of the former field, but the proportion of NTFP species declined from 80% in the youngest former fields to 65% in the oldest ones, which were similar to the 63% recorded within intact forests. The youngest former fields had more medicinal species than the older ones, as the abundance and diversity of herbaceous species declined with increasing woody plant cover. Species used for building and food (especially fruits) peaked when the former fields became dominated by woody plants. NTFPs used for craft were most abundant in the oldest sites.

Provitamin A Carotenoids, Tocopherols, Ascorbic Acid and Minerals in Indigenous Leafy Vegetables from Tanzania

The essential micronutrients in indigenous leafy vegetables (ILVs) could substantially contribute to the micronutrient supply in rural communities in Tanzania, but concentrations differ between species. Provitamin A carotenoids, tocopherols, ascorbic acid, minerals, and phytate were analysed in 13 different species using HPLC-, ICP-OES, and photometric techniques. Eight of the 13 ILVs, including Amaranthus ssp. and Sesamum angustifolium, had high β-carotene concentrations (2.91–4.84 mg/100 g fresh weight), which could provide ≥50% of vitamin A’s recommended nutrient intake (RNI). Six ILVs including Cleome hirta and Sonchus luxurians had high iron contents (34.5–60.4 mg/100 g, >50% RNI); Amaranthus ssp. represented the ILV with high calcium, magnesium and zinc contents (85%, 207% and 21% of RNI per 100 g); Cleome hirta and Cleome gynandra had high ascorbic acid contents (>15 mg/100 g, 34–35% of RNI), while Sesamum angustifolium was the only ILV with a high tocopherol content (7.34 mg α-TE/100 g). The highest phytate concentration was found in Amaranthus ssp., which could negatively affect its role as a very good source of minerals. Results indicate that the analysed ILVs could make a substantial contribution to the vitamin A and iron supply in the diets of rural Tanzanian populations.

Open-source food: Nutrition, toxicology, and availability of wild edible greens in the East Bay

Significance

Foraged leafy greens are consumed around the globe, including in urban areas, and may play a larger role when food is scarce or expensive. It is thus important to assess the safety and nutritional value of wild greens foraged in urban environments.

Methods

Field observations, soil tests, and nutritional and toxicology tests on plant tissue were conducted for three sites, each roughly 9 square blocks, in disadvantaged neighborhoods in the East San Francisco Bay Area in 2014–2015. The sites included mixed-use areas and areas with high vehicle traffic.

Results

Edible wild greens were abundant, even during record droughts. Soil at some survey sites had elevated concentrations of lead and cadmium, but tissue tests suggest that rinsed greens of the tested species are safe to eat. Daily consumption of standard servings comprise less than the EPA reference doses of lead, cadmium, and other heavy metals. Pesticides, glyphosate, and PCBs were below detection limits. The nutrient density of 6 abundant species compared favorably to that of the most nutritious domesticated leafy greens.

Conclusions

Wild edible greens harvested in industrial, mixed-use, and high-traffic urban areas in the San Francisco East Bay area are abundant and highly nutritious. Even grown in soils with elevated levels of heavy metals, tested species were safe to eat after rinsing in tap water. This does not mean that all edible greens growing in contaminated soil are safe to eat—tests on more species, in more locations, and over a broader range of soil chemistry are needed to determine what is generally safe and what is not. But it does suggest that wild greens could contribute to nutrition, food security, and sustainability in urban ecosystems. Current laws, regulations, and public-health guidance that forbid or discourage foraging on public lands, including urban areas, should be revisited.

Transcriptome analysis by Illumina high-throughout paired-end sequencing reveals the complexity of differential gene expression during in vitro plantlet growth and flowering in Amaranthus tricolor L

Amaranthus tricolor L. is a C4 plant, which is consumed as a major leafy vegetable in some tropical countries. Under conditions of high temperature and short daylight, Am. tricolor readily bolts and blooms, degrading leaf quality. A preliminary in vitro flowering study demonstrated that the flowering control pathway in Am. tricolor may differ from that of Arabidopsis. Nevertheless, no transcriptome analysis of the flowering process in Amaranthus has been conducted. To study Am. tricolor floral regulatory mechanisms, we conducted a large-scale transcriptome analysis--based on Illumina HiSeq sequencing of cDNA libraries generated from Am. tricolor at young seedling (YSS), adult seedling (ASS), flower bud (FBS), and flowering (FS) stages. A total of 99,312 unigenes were obtained. Using BLASTX, 43,088 unigenes (43.39%) were found to have significant similarity with accessions in Nr, Nt, and Swiss-Prot databases. Of these unigenes, 11,291 were mapped to 266 KEGG pathways. Further analysis of the four digital transcriptomes revealed that 735, 17,184, 274, and 206 unigenes were specifically expressed during YSS, ASS, FBS, and FS, respectively, with 59,517 unigenes expressed throughout the four stages. These unigenes were involved in many metabolic pathways related to in vitro flowering. Among these pathways, 259 unigenes were associated with ubiquitin-mediated proteolysis, indicating its importance for in vitro flowering in Am. tricolor. Other pathways, such as circadian rhythm and cell cycle, also had important roles. Finally, 26 unigenes were validated by qRT-PCR in samples from Am. tricolor at YSS, ASS, FBS, and FS; their differential expressions at the various stages indicate their possible roles in Am. tricolor growth and development, but the results were somewhat similar to Arabidopsis. Because unigenes involved in many metabolic pathways or of unknown function were revealed to regulate in vitro plantlet growth and flowering in Am. tricolor, the process appears to be highly complex in this species.

Comparative analysis of plant use in peri-urban domestic gardens of the Limpopo Province, South Africa

BACKGROUND

Relatively little has been researched or published on the importance of peri-urban domestic gardens as part of a household livelihood strategy in South Africa. Due to lack of comprehensive data on peri-urban domestic gardens, their potential value as luxury green space, provision of food, income and ecosystem services to the fast growing urban population in South Africa is not clearly known. The aim of this study was to document differences and similarities in plant use and diversity in domestic gardens of two peri-urban communities in the Limpopo Province that differ in proximity to an urban area.

METHODS

Data on plant use categories of 62 domestic gardens in the peri-urban areas of the Limpopo Province were collected in Seshego and Lebowakgomo. Semi-structured interviews, observation and guided field walks with 62 participants were employed between May and October 2012.

RESULTS

A total of 126 plant species were recorded for both Seshego and Lebowakgomo. Domestic gardens in the more remote areas of Lebowakgomo were characterized by higher percentage of food plants (47 species, 83.8% of the total food plants recorded) and medicinal plants (31 species, 83.7%). Lebowakgomo domestic gardens were also characterized by higher numbers of indigenous plants (76.7%) showing similarities to the natural surrounding vegetation in terms of plant species. On the contrary, domestic gardens of Seshego on the periphery of the city centre were characterized by higher percentage of exotic species (81.8%) and ornamental plants (73%), with food plants playing a supplementary role. Comparison of the two areas demonstrated a remarkable difference in plant use and composition.

CONCLUSIONS

This study revealed that there are differences in utilization of plant resources between households on the edge of an urban centre and those in the more remote areas. Food and medicinal plants play an important role in remote areas; while ornamental plants play an important role in urban domestic gardens. But the collective desire for food, medicinal and ornamental plants by both communities on the edge of an urban centre and those in the more remote areas highlight the importance of plant resources in domestic gardens.