Neglected and Underutilized Cultivated Crops with Respect to Indigenous African Leafy Vegetables for Food and Nutrition Security

Samuel Imathiu^1,

¹Department of Food Science and Technology, School of Food and Nutrition Sciences, Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62000 - 00200, Nairobi, Kenya

Cite this paper

Samuel Imathiu. Neglected and Underutilized Cultivated Crops with Respect to Indigenous African Leafy Vegetables for Food and Nutrition Security. Journal of Food Security. 2021; 9(3):115-125. doi: 10.12691/JFS-9-3-4

Abstract

Many neglected and underutilized vegetable species such as indigenous African leafy vegetables have been incorporated in human diets since time immemorial, especially in sub-Saharan Africa and many Asian countries where they greatly contribute to food and nutrition security. Due to their well-documented superior nutritional quality and climate-smartness compared to their exotic counterparts, many of them are currently receiving a lot of attention among many stakeholders including governments, researchers, nutritionists, consumers and farmers. As a result of their climate adaptability and high micronutrient content, they can be used to curb ‘hidden hunger’ most prevalent in developing countries, contributing to the achievement of some of the UN’s Sustainable Development Goals; no poverty, zero hunger, and good health and wellbeing. In this review, the general role of neglected and underutilized vegetable species, and indigenous African leafy vegetables in particular, is discussed with respect to their contribution to food and nutrition security. The benefits of embracing increased production and consumption of these vegetables in the context of developing countries, especially among the under-privileged rural poor is highlighted. In addition, challenges facing production and consumption of these vegetables are discussed and recommendations for research gaps suggested with the ultimate aim of ensuring that the commodity’s full potential is realized.

Keywords

food losses, food security, indigenous leafy vegetables, neglected and underutilized species, nutrition, traditional vegetables

Copyright

This work is licensed under a Creative Commons Attribution 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/

References

[1]	FAO, IFAD, UNICEF, WFP and WHO., 2018. The State of Food Security and Nutrition in the World ,2018. Building climate resilience for food security and nutrition. Rome, FAO.
[2]	FAO, IFAD, UNICEF, WFP and WHO., 2019. The State of Food Security and Nutrition in the World 2019. Safeguarding against economic slowdowns and downturns. Rome, FAO.
[3]	World Food Summit, 1996. Rome Declaration on World Food Security.
[4]	Premanandh, J., 2011. Factors affecting food security and contribution of modern technologies in food sustainability. Journal of the Science of Food and Agriculture, 91: 2707-2714.
[5]	Li X. and Siddique K.H.M., 2018. Future Smart Food - Rediscovering hidden treasures of neglected and underutilized species for Zero Hunger in Asia. Food and Agriculture Organization of the United Nations, Bangkok, pp 242.
[6]	Willett, W., Rockström, J., Loken, B., Springmann, M., Lang, T., Vermeulen, S., et al., 2019. Food in the Anthropocene: the EAT-Lancet Commission on healthy diets from sustainable food systems. Lancet, 393: 447-492.
[7]	Waha, K., van Wijk, M.T., Fritz, S., See, L., Thornton, P.K., Wichern, J., Herrero, M., 2018. Agricultural diversification as an important strategy for achieving food security in Africa. Global Change Biology, 24: 3390-3400.
[8]	McCord, P. F., Cox, M., Schmitt-Harsh, M., Evans, T., 2015. Crop diversification as a smallholder livelihood strategy within semi-arid agricultural systems near Mount Kenya. Land Use Policy, 42: 738-750.
[9]	Bekunda, M., Sanginga, N., Woomer, P.L., 2010. Restoring soil fertility in sub-Sahara Africa. Advances in Agronomy, 108: 183-236.
[10]	Hunter, D., Teresa, B.T., Daniela, M.O., Beltrame, D.M.O., Camila, N.S., Oliveira, C.N.S., Coradin, L., Wasike, V.W., Wasilwa, L., Mwai, J., Manjella, A., Samarasinghe, G.W.L., Madhujith, T., Nadeeshani, H.V.H., Tan, A., Ay, S.T., Güzelsoy, N., Lauridsen, N., Eliot, G.E., Tartanac, F., 2019. The potential of neglected and underutilized species for improving diets and nutrition. Plant, 250: 709-729.
[11]	Prescott-Allen and Prescott-Allen, 1990. How many plants feed the world? Conservation Biolology, 4: 365-374.
[12]	Nakhauka, E.B., 2009. Agricultural biodiversity for food and nutrient security: The Kenyan perspective. International Journal of Biodiversity Conservation, 1: 208-214.
[13]	Luchuo, E.B., Paschal, K.A., Ngia, G., Njem, P.K., Yelena, S., Nsah, B., Ajime, T.T., 2013. Malnutrition in Sub-Saharan Africa: burden, causes and prospects. Pan African Medical Journal, 15: 120.
[14]	Popkin, B.M., 2006. Technology, transport, globalization and the nutrition transition food policy. Food Policy, 31: 554-569.
[15]	Siegel, K.R., Ali, M.K., Srinivasiah, A., Nugent, R.A., Venkat, N.K., 2014. Do we produce enough fruits and vegetables to meet global health need? PLoS One, 9: e104059.
[16]	Willett, W., Rockström, J., Loken, B., Springmann, M., Lang, T., Vermeulen, S., et al., 2019. Food in the Anthropocene: the EAT-Lancet Commission on healthy diets from sustainable food systems. Lancet, 393: 447-492.
[17]	FAO., 2012. Neglected crops need a rethink - can help world face the food security challenges of the future. Available at www.fao.org/news/story/en/item/166368/icode/, accessed on 13/08/2020.
[18]	FAO., 2010. The second report on the state of the world’s plant genetic resources for food and agriculture. FAO, Rome.
[19]	Meldrum, G., Padulosi, S., Lochetti, G., Robitaille, R., Diulgheroff, S., 2018. Issues and prospects for the sustainable use and conservation of cultivated vegetable diversity for more nutrition-sensitive agriculture. Agriculture, 8: 1-21.
[20]	Sogbohossou, E.O.D., Achigan-Dako, E.G., Mumm, R., de Vos, R.C.H., Schranz, M.E., 2020. Natural variation in specialized metabolites production in the leafy vegetable spider plant (Gynandropsis gynandra L. (Briq.)) in Africa and Asia. Phytochemistry, 178: 1-10.
[21]	Padulosi, S., Hodgkin, T., Williams, J.T., Haq, N., 2002. Underutilized crops: trends, challenges and opportunities in the 21st century, pp 323-338. In Managing Plant Genetic Diversity. Proceedings of an international conference, Kuala Lumpur, Malaysia, 12-16 June 2000 (Engels, J. M. M., Ramanatha Rao, V., Brown, A. H. D. & Jackson, M. T., eds.).
[22]	Padulosi, S., Thompson, J., Rudebjer, P., 2013. Fighting poverty, hunger and malnutrition with neglected and underutilized species: Needs, challenges and the way forward. Biodiversity International, Rome.
[23]	Royal Botanic Gardens Kew., 2016. The state of the world’s plants report 2016. Royal Botanic Gardens Kew, Richmond.
[24]	Wilson, E.O., 1988. Biodiversity. National Academy Press, Washington, D.C.
[25]	Mabhaudhi, T., Chimonyo, V.G.P., Chibarabada, T.P., Modi, A.T., 2017. Developing a roadmap for improving neglected and underutilized crops: A case study of South Africa. Frontiers in Plant Science, 8: 2143.
[26]	FAO/IAEA., 2004. Genetic improvement of under-utilized and neglected crops in low income food deficit countries through irradiation and related techniques. Proceedings of a final research coordination meeting (IAEA-TECDOC-1426). International Atomic Energy Agency (IAEA). Division of Nuclear Techniques in Food and Agriculture, Vienna
[27]	Nyadanu, D. and Lowor, S.T., 2015. Promoting competitiveness of neglected and underutilized crop species: comparative analysis of nutritional composition of indigenous and exotic leafy and fruit vegetables in Ghana. Genetic Resources and Crop Evolution volume 62, pages 131-140.
[28]	Rutto, L.K., Temu, V.W., Ansari, M.S., 2016. Genetic Vulnerability and Crop Loss: The Case for Research on Underutilized and Alternative Crops. Mathematical Sciences with Multidisciplinary Applications, pp. 465-479. Springer International Publishing.
[29]	Padulosi, S., Thompson, J., Rudebjer, P., 2013. Fighting poverty, hunger and malnutrition with neglected and underutilized species: Needs, challenges and the way forward. Biodiversity International, Rome.
[30]	Conti, M.V., Campanaro, A., Coccetti, P., De Giuseppe, R., Galimberti, A., Labra, M., Cena, H., 2019. Potential role of neglected and underutilized plant species in improving women’s empowerment and nutrition in areas of sub-Saharan Africa. Nutrition Reviews, 77: 817-828.
[31]	Kobori, N.C., Rodriguez-Amaya, D.B., 2008. Uncultivated Brazilian green leaves are richer sources of carotenoids than are commercially produced leafy vegetables. Food Nutrition Bulletin, 29: 320-328.
[32]	McGarry, D.K., Shackleton, C.M., 2009. Children navigating rural poverty: rural children’s use of wild resources to counteract food insecurity in the Eastern Cape province, South Africa. Journal of and Children Poverty, 15: 19-37.
[33]	Asghari, G., Palizban, A., Bakhshaei, B., 2015. Quantitative analysis of the nutritional components in leaves and seeds of the Persian Moringa peregrina (Forssk). Pharmacognosy Research, 7: 242-248.
[34]	Dulloo, E., Hunter, D., Leaman, D.L., 2014. Plant diversity in addressing food, nutrition and medicinal needs. In: Garib-Fakim,, A. (Ed). Novel plant bioresources: application in food, medicine and cosmetics. Wiley-Blackwell, Chichester, pp 1-21.
[35]	Hossain, S., Ahmed, R., Bhowmick, S., Mamun, A.A., Hashimoto, M., 2016. Proximate composition and fatty acid analysis of Lablab purpureus (L.) legume seed: implicates to both protein and essential fatty acid supplementation. Springerplus, 5: 1899.
[36]	Li, X., Yadav, R. and Siddique, K.H.M., 2020. Neglected and underutilized crop species: The key to improving dietary diversity and fighting hunger and malnutrition in Asia and the Pacific. Frontiers in Nutrition, 7: 593711.
[37]	Padulosi, S., Heywood, V., Hunter, D., Jarvis, A., 2011. Underutilized Species and Climate Change: Current Status and Outlook, pp 507-521. In Crop Adaptation to Climate Change (Shyam, S., Yadav, S.S., Redden, R.J., Hatfield, J.L., Lotze-Campen, H., & Hall, A.E. Eds). Wiley Online Library. Available at https://onlinelibrary.wiley.com/doi/10.1002/9780470960929.ch35 and accessed on 14/08/2020.
[38]	Bvenura, C., Sivakumar, D., 2017. The role of wild fruits and vegetables in delivering a balanced and healthy diet. Food Research International, 99: 15-30.
[39]	Ezzati, M., Lopez, A.D., Rodgers, A., van der Hoorn, S., Murray, C.J.L., 2002. Selected major risk factors and global and regional burden of disease. Lancet, 360: 1347-1360.
[40]	Schneider, M., Norman, R., Steyn, N., Bradshaw, D.. 2007. South African Comparative Risk Assessment Collaborating Group. 2007. Estimating the burden of disease attributable to low fruit and vegetable intake in South Africa in 2000. South African Medical Journal, 97: 717-723.
[41]	Toledo, A., Burlingame, B., 2006. Biodiversity and nutrition: A common path toward global food security and sustainable development. Journal of Food Composition and Analysis, 19: 477-483.
[42]	Martin, F. W., Ruberte, R.M., Meitzner, L.S., 1998. Edible leaves of the tropics. Educational Concerns for Hunger Organization, Inc. North Fort Myers, Florida.
[43]	Kwenin, W.K.J., Wolli, M., Dzomeku, B.M., 2011. Assessing the nutritional value of some African indigenous green leafy vegetables in Ghana. Journal of Animal and Plant Science, 10: 1300-1305.
[44]	Akhtar, S., Karak, C., Biswas, P., Chattopadhyay, A., Hazra, P., 2012. Indigenous leafy vegetables: A potential source of β-carotene and ascorbic acid. International Journal of Vegetable Science, 18: 370-375.
[45]	Obedy, E., Ayuya, O.I., Owuor, G. and Bokelmann, W., 2017. Consumption intensity of leafy African indigenous vegetables: towards enhancing nutritional security in rural and urban dwellers in Kenya, Agricultural and Food Economics, ISSN 2193-7532, Springer, Heidelberg, Vol. 5, Iss. 14, pp. 1-16.
[46]	Virchow, D., 2003. Leipzig declaration on conservation and sustainable utilization of plant genetic resources for food and agriculture. Efficient conservation of crop genetic diversity, Springer Berlin Heidelberg, Bohn, Germany.
[47]	Chivengem P., Mabhaudhi, T., Modi, A.T., Mafongoya, M., 2015. The potential role of neglected and underutilized crop species as future crops under water scarce conditions in sub-Saharan Africa. International Journal of Environmental Research and Public Health, 12, 5685-5711.
[48]	Baldermann, S., Blagojević, L., Frede, K., Klopsch, R., Neugart, S., Neumann, A., Ngwene, B., Norkeweit, J., Schröter, D., Schröter, A., Schweigert, F.J., Wiesner, M., Schreiner, M., 2016. Are neglected plants the food for the future? Critical Reviews in Plant Sciences, 35: 106-119.
[49]	Maundu, P., Achigan-Dako, E., Morimoto, Y., 2009. Biodiversity of African vegetables. In: African indigenous vegetables in urban agriculture, Shackleton, C. M., Pasquini, M, & Drescher, A. (Eds), pp 65-104. London: Earthscan.
[50]	Garekae, H. and Shackleton, C.M., 2020. Foraging wild food in urban spaces: The contribution of wild foods to urban dietary diversity in South Africa. Sustainability, 12, 678.
[51]	van Rensburg, W., Vorster, I.H.J., Van Zijl, J.J.B., Venter, L.S., 2007. Conservation of African leafy vegetables in South Africa. African Journal of Food, Agriculture, Nutrition and Development, 7: 1-13.
[52]	Humphrym C.M., Clegg, M.S., Keen, C.L., Grivetti, L.E., 1993. Food diversity and drought survival: The Hausa example. International Journal of Food Sciences and Nutrition, 44: 1-16.
[53]	Smith, I.F. and Eyzaguirre, P., 2007. African leafy vegetables: their role in World Health Organization’s global fruit and vegetable initiative. African Journal of Food, Agriculture, Nutrition and Development, 7: 1-17.
[54]	Uusiku, N.P., Oelofse, A., Duodu, K.G., Bester, M.J., Faber, M., 2010. Nutritional value of leafy vegetables of sub-Saharan Africa and their potential contribution to human health: A review. Journal of Food Composition and Analysis, 23: 499-509.
[55]	Cernansky, R., 2015. The rise of Africa’s super vegetables. Nature, 522: 146-148.
[56]	Slabbert, R., Spreeth, M., Kruger, G.H.J., Bornman, C.H., 2004. Drought tolerance, traditional crops and biotechnology: Breeding towards sustainable development. South African Journal of Botany, 70: 116-123.
[57]	Aworh, O.C., 2018. From lesser-known to super vegetables: The growing profile of African traditional leafy vegetables in promoting food security and wellness. Journal of the Science of Food and Agriculture, 98: 3609-3613.
[58]	Garekae, H. and Shackleton, C.M., 2020. Foraging wild food in urban spaces: The contribution of wild foods to urban dietary diversity in South Africa. Sustainability, 12, 678.
[59]	Bua, B., Onag, C., 2017. Validating the role of African indigenous vegetables for food and nutrition security in Uganda. Journal of Food Science and Engineering, 7: 316-322.
[60]	Irungu, C., Mburu, J., Maundu, P., Grum, M., Hoeschle, Z.I., 2008. The effect of market development on-farm conservation of diversity of African leafy vegetables around Nairobi. 12th European Association of Agricultural Economists Congress, People, Food and Environments: Global Trends and European Strategies, Ghent, Belgium, 26-29 Aug. 2008.
[61]	Senyolo, M.G., Wale, E., Ortmann, F.G., 2014. Consumers’ willingness-to-pay for underutilized vegetable crops: the case of African leafy vegetables in South Africa. Journal of Human Ecology, 47: 219-227.
[62]	Chelang’a, P.K., Obare, G.A., Kimenju, S.C., 2013. Analysis of urban consumers’ willingness to pay a premium for African Leafy Vegetables (ALVs) in Kenya: A case of Eldoret Town. Food Security, 5: 591-595.
[63]	Hughes, J., 2009. Just famine foods? What contributions can underutilized plants make to food security? Acta Horticulturae, 806: 39-48.
[64]	Van Rensburg, J.W.S., Venter, S.L., Netshiluvhu, T.R., Van Den Heever, E., Vorster, H.J., De Ronde, J.A., 2004. The role of indigenous leafy vegetables in combating hunger and malnutrition. South African Journal of Botany, 70: 52-59.
[65]	WHO., 2003. Diet, nutrition and the prevention of chronic diseases. Report of a Joint FAO/WHO Expert Consultation. WHO Technical Report Series No. 916. World Health Organization, Geneva, Switzerland.
[66]	Lock, K., Pomerleau, J., Cause, L., Altmann, D.R., McKee, M., 2005. The global burden of disease attributable to low consumption of fruit and vegetables: implications for the global strategy on diet. Bulletin of the World Health Organization, 83: 100-108.
[67]	Cheptoo, G., Owino, W. and Kenji, G., 2019. Nutritional quality, bioactive compounds and antioxidant activity of selected african indigenous leafy vegetables as influenced by maturity and minimal processing. African Journal of Food, Agriculture, Nutrition and Development, 19, 14769-14789.
[68]	Gogo, E.O., Opiyo, A.M., Hassenberg, K., Ulrichs, C., Huyskens-Keil, S., 2017. Postharvest UV-C treatment for extending shelf life and improving nutritional quality of African indigenous leafy vegetables. Postharvest Biology and Technology, 129: 107-117.
[69]	Natesh, H.N., Abbey, L., Asiedu, S.K., 2017. An overview of nutritional and antinutritional factors in green leafy vegetables. Horticulture International Journal, 1: 58-65.
[70]	Van de Heever E., 1995. The use and conservation of indigenous leafy vegetables. Roodeplaat Bulletin, 45: 16-17.
[71]	Van Vuuren L., 2006. Wild vegetables: Tamed to decrease hunger: Emerging Agriculture. The Water Wheel, 5: 22-25.
[72]	Van Jaarsveld, P., Faber, M., Van Heerden, I., Wenhold, F., van Rensburg, W.J., Van Averbeke, W., 2014. Nutrient content of eight African leafy vegetables and their potential contribution to dietary reference intakes. Journal of Food Composition and Analysis, 33: 77-84.
[73]	Pennington, J.A.T., Fisher, R.A., 2010. Food component profiles for fruit and vegetable subgroups. Journal of Food Composition and Analysis, 23: 411-418.
[74]	Van Rensburg, J.W.S., Venter, S.L., Netshiluvhu, T.R., Van Den Heever, E., Vorster, H.J., De Ronde, J.A., 2004. The role of indigenous leafy vegetables in combating hunger and malnutrition. South African Journal of Botany, 70: 52-59.
[75]	Schonfeldt, H.C. and Pretorius, B., 2011. The nutrient content of five traditional South African dark green leafy vegetables - A preliminary study. Journal of Food Composition and Analysis, 24: 1141-1146.
[76]	Stadlmayr, B., Charrondiere, U.R., Eisenwagen, S., Kehlenbeck, K., Jamnadass, R.H., 2013. Nutrient composition of selected indigenous fruits from sub-Saharan Africa. Journal of Science of Food and Agriculture, 93: 2627-2636.
[77]	Biesalski, H.K., Drewnowsk, A., Dwyer, J.T., Strain, J.J., Weber, P., Eggersdorfer, M., (Eds) 2017. Sustainable nutrition in a changing world. Cham, Switzerland: Springer International Publishing.
[78]	Francis, G., Kerem, Z., Makkar, H.P.S., Becker, K., 2002. The biological action of saponins in animal systems: a review. British Journal of Nutrition, 88: 587-605.
[79]	Podsędek, A., 2007. Natural antioxidants and antioxidant activity of Brassica vegetables: a review. LWT- Food Science and Technology, 40: 1-11.
[80]	Manach, C., Mazur, A., Scalbert, A., 2005. Polyphenols and prevention of cardiovascular diseases. Current Opinion in Lipidology, 16: 77-84.
[81]	Moyo, M., Amoo, S.O., Ncube, B., Ndhlala, A.R., Finnie, J.F., Van Staden, J., 2013. Phytochemical and antioxidant properties of unconventional leafy vegetables consumed in southern Africa. South African Journal of Botany, 84: 65-71.
[82]	Mertz, C., Gancel, A.L., Gunata, Z., Alter, P., Dhuique-Mayer, C., Vaillant, F., Perez, A.N., Ruales, J., Brat, P., 2009. Phenolic compounds, carotenoids and antioxidant activity of three tropical fruits. Journal of Food Composition and Analysis, 22: 381-387.
[83]	Afolayan, A.J., Jimoh, F.O., 2009. Nutritional quality of some wild leafy vegetables in South Africa. International Journal of Food Science and Nutrition, 60: 424-431.
[84]	Kaur, C., Kapoor, H.C., 2002. Anti-oxidant activity and total phenolic content of some Asian vegetables. International Journal of Food Science and Technology, 37: 153-161.
[85]	Neugart, S., Baldermann, S., Ngwene, B., Wesonga, J., Schreiner, M., 2017. Indigenous leafy vegetables of Eastern Africa - A source of extraordinary secondary plant metabolites. Food Research International, 100: 411-422.
[86]	Kopsell, D.A., Kopsell, D.E., 2006. Accumulation and bioavailability of dietary carotenoids in vegetable crops. Trends in Plant Science, 11: 499-507.
[87]	Akhtar, S., Karak, C., Biswas, P., Chattopadhyay, A., Hazra, P., 2012. Indigenous leafy vegetables: A potential source of β-carotene and ascorbic acid. International Journal of Vegetable Science, 18: 370-375.
[88]	Abukutsa-Onyango, M., 2007. The diversity of cultivated African leafy vegetables in three communities in western Kenya. African Journal of Food Agriculture Nutrition and Development, 7: 1-15.
[89]	Schippers, R.R., 2000. African indigenous vegetables. An overview of the cultivated species. Chatham, U.K. Natural Resources Institute/ACPEU Technical Centre for Agriculture and Rural Cooperation.
[90]	Bua, B., Onag, C., 2017. Validating the role of African indigenous vegetables for food and nutrition security in Uganda. Journal of Food Science and Engineering, 7: 316-322.
[91]	Adebooye, O.C., Opabode, J.T., 2004. Status of conservation of the indigenous leaf vegetables and fruits of Africa. African Journal of Biotechnology, 3: 700-705.
[92]	Gockowski, J., Mbazo’o, J., Mbah, G., Moulende, T.M., 2003. African traditional leafy vegetables and the urban and peri-urban poor. Food Policy, 28: 221-235.
[93]	Weinberger, K., Pichope, G.N., 2009. Marketing of African indigenous vegetables along the urban and peri-urban supply chains in sub-Saharan Africa. In: African indigenous vegetables in urban agriculture, Shackleton, C. M., Pasquini, M., & Drescher, A.W. (Eds), pp 225-244. EarthScan, London.
[94]	Weinberger, K. and Msuya, J., 2004. Indigenous vegetables in Tanzania-significance and prospects. Asian Vegetable Research and Development Center, Technical Bulletin No. 31, Publication 04-600, Shanhua, Taiwan.
[95]	Ngugi, I.K., Gitau, R. and Nyoro, J.K., 2007. Access to high value markets by smallholder farmers of African indigenous vegetables in Kenya. London: IIED.
[96]	High, C. and Shackleton, C.M., 2000. The comparative value of wild and domestic plants in home gardens of a South African rural village. Agroforestry Systems, 48: 141-156.
[97]	Kansiime, M., Nicodemus, J., Makuya, P,. 2017. Development of market opportunities through post-harvest processing of the African indigenous vegetables in Tanzania. African Journal of Business Management, 11: 426-437.
[98]	Chepkoech, W., Mungai, N.W., Stober, S., Lotze-Campen, H., 2020. Understanding adaptive capacity of smallholder African indigenous vegetable farmers to climate change in Kenya. Climate Risk Management, 27: (100204).
[99]	Phiiri, G.K., Egeru, A., Ekwamu, A., 2016. Climate change and agriculture nexus in sub-Saharan Africa: the agonizing reality for smallholder. International Journal of Current Pharmaceutical Review and Research, 8: 57-64.
[100]	Van Der Walt, A.M., Mossanda, A.M., Jivan, K.S.A., Swart, S.D. and Bezuidenhout, C,C., 2005. Indigenous African food plants: Vehicles of diseases or source of protection. Indilinga: African Journal of Indigenous Knowledge Systems, 4: 279.
[101]	Thompson, J., Hodgkin, T., Atta-Krah, K., Jarvis, D., Hoogendoorn, C. and Padulosi, S., 2007. Biodiversity in agroecosystems farming with nature: the science and practice of eco-agriculture, pp. 46-60. In: Scherr, S.J., & McNeely, J.A. (eds.). The Science and Practice of Ecoagriculture. Island Press, Washington, DC
[102]	Oelofse, A. and van Averbeke W., 2012. Nutritional value and water use of African leafy vegetables for improved livelihoods; WRC TT535/12; Water Research Commission: Pretoria, South Africa.
[103]	Singh, B.B., Ajeigbe, H.A., Tarawali, S., Fernandez-Rivera, S. and Abubakar, M., 2003. Improving the production and utilization of cowpea as food and fodder. Field Crops Research, 84: 169-177.
[104]	Neluheni, K., Du Plooy, C.P. and Mayaba, N., 2007. Yield response of leafy amaranths to different irrigation regimes. African Crop Science Conference Proceedings, 8: 1619-1623.
[105]	Maseko, I., Mabhaudhi, T., Tesfay, S., Araya, H.T., Fezzehazio, M. and Plooy, C.P.D., 2017. African leafy vegetables: A review of status, production and utilization in South Africa. Sustainability, 10: 2-16.
[106]	Darkwa, S. and Darkwa, A.A., 2013. The use of indigenous green leafy vegetables in the preparation of Ghanaian dishes. Food Processing and Technology, 4: 12.
[107]	Meldrum, G., Padulosi, S., Lochetti, G., Robitaille, R. and Diulgheroff, S., 2018. Issues and prospects for the sustainable use and conservation of cultivated vegetable diversity for more nutrition-sensitive agriculture. Agriculture, 8: 1-21.
[108]	Asase, A. and Kumordzie, S., 2018. Availability, cost, and popularity of African leafy vegetables in Accra markets, Ghana. Economic Botany, 72: 450-460.
[109]	Dweba, T.P. and Mearns, M.A., 2011. Conserving indigenous knowledge as the key to the current and future use of traditional vegetables. International Journal of Information Management, 31: 564-571.
[110]	Van Rensburg, J.W.S/, Venter. S.L., Netshiluvhu, T.R., Van Den Heever, E., Vorster, H.J. and De Ronde, J.A., 2004. The role of indigenous leafy vegetables in combating hunger and malnutrition. South African Journal of Botany, 70: 52-59.
[111]	Chivenge, P., Mabhaudhi, T., Modi, A.T. and Mafongoya, M., 2015. The potential role of neglected and underutilized crop species as future crops under water scarce conditions in sub-Saharan Africa. International Journal of Environmental Research and Public Health, 12, 5685-5711.
[112]	Matenge, S.T.P., van der Merwe, D., de Beer, H., Bosman, M.J.C. and Kruger, A., 2012. Consumers’ beliefs on indigenous and traditional foods and acceptance of products made with cow pea leaves. African Journal of Agricultural Research, 7: 2243-2254.
[113]	Gido, E.O., Ayuya, O.I., Owuor, G. and Bokelmanna, W., 2017a. Consumption intensity of leafy African indigenous vegetables: towards enhancing nutritional security in rural and urban dwellers in Kenya. Agricultural and Food Economics, 5: 1-16.
[114]	Vorster, H.J., Van Rensburg, W.J/, Venter, S.L., Van Zijl, J.J.B., 2005. (Re)-creating awareness of traditional leafy vegetables in communities. In Proceedings of the Regional Workshop on African Leafy Vegetables for Improved Nutrition, IPGRI, Nairobi, Kenya, 6-9 December 2005.
[115]	Ezeanya-Esiobu, C., Taremwa, N.K., Nambajimana, D. and Mugwaneza, O., 2018. Indigenous vegetable production and the economic empowerment of rural women in Africa: Reality, prospects, and challenges in Rwanda. IK: Other Ways of Knowing, 4: 133-156.
[116]	Onyango, C.M. and Imungi, J.K., 2007. Postharvest handling and characteristics of fresh-cut traditional vegetables sold in Nairobi-Kenya. African Crop Science Journal, 8: 1791-1794.
[117]	Gogo, E.O., Opiyo, A., Ulrichs, C. and Huyskens-Keil, S., 2016. Postharvest treatments of African leafy vegetables for food security in Kenya: a review. African Journal of Horticultural Science, 9: 32-40.
[118]	Voster, I.H.J., van Rensburg, W., nan Zijl, J.J.B., Sonja, L.B., 2007. The importance of traditional leafy vegetables in South Africa. African Journal of Food, Agriculture, Nutrition and Development, 7: 1-13.
[119]	Vorster, H.J., Van Rensburg, W.J., Venter, S.L. and Van Zijl, J.J.B., 2005. (Re)-creating awareness of traditional leafy vegetables in communities. In Proceedings of the Regional Workshop on African Leafy Vegetables for Improved Nutrition, IPGRI, Nairobi, Kenya, 6–9 December 2005.
[120]	Misci, C., Taskin, E., Dall’Asta, M., Fontanella, M.C., Bandini, F., Imathiu, S., Sila, D., Bertuzzi, T., Cocconcelli, P.S. and Puglisi, E., 2021. Fermentation as a tool for increasing food security and nutritional quality of indigenous African leafy vegetables: the case of Cucurbita sp. Food Microbiology, 99, 103820.
[121]	Gido, E.O., Ayuya, O.I., Owuor, G. and Bokelmanna, W., 2017b. Consumer acceptance of leafy African indigenous vegetables: Comparison between rural and urban dwellers. International Journal of Vegetable Science, 23: 346-361.