17 May 2021, UN: The many fruit and vegetable species in food production systems contributing essential nutrients to human diets are under threat from land use, climate change, and other factors, reports a United Nations Food Systems Summit (UNFSS) 2021 brief prepared by scientists working for member organisations of Association of International Research and Development Centers for Agriculture (AIRCA).
The brief, entitled ‘Safeguarding and Using Fruit and Vegetable Biodiversity’, warns that declining biodiversity limits options for a sustainable, healthy food supply.
As Research Partners of the Scientific Group for the Food Systems Summit 2021, authors Dr Maarten van Zonneveld of the World Vegetable Center; Dr Gayle M. Volk, US Department of Agriculture; Dr E. Ehsan Dulloo, Bioversity International; Dr Roeland Kindt, World Agroforestry Centre; Dr Sean Mayes, Crops for the Future; Dr Marcela Quintero, International Center for Tropical Agriculture; Dr Dhrupad Choudhury, International Centre for Integrated Mountain Development; Dr Enoch G. Achigan-Dako University of Abomey-Calavi; and Dr Luigi Guarino of the Crop Trust prepared the brief to propose a 10-year rescue plan for protecting genetic resources of the food plant species that contribute an astonishing array of colours, textures, flavours, and most importantly, vital nutrients to diets.
The plan aims to ensure fruit and vegetables can fulfil their increasingly prominent role in a new global research and development agenda emphasizing nutrition and healthy diets alongside climate action, safeguarding biodiversity, ending poverty, and improving livelihoods.
Poorly conserved and largely undocumented
While a few globally popular crops such as tomatoes or bananas absorb scarce research funds, less well-known fruit and vegetable species and their wild relatives languish from a lack of attention. The researchers report that a quarter of the 1,100 recognized vegetable species worldwide are not conserved in genebanks.
Wild relatives of fruit and vegetables—the source of traits for heat and drought tolerance, pest and disease resistance, colour, shape, taste, nutrients, yield and more—are poorly represented in genebanks. About 39% of 883 wild fruit and veg relatives require urgent conservation and 58% are a medium priority for protection. Only 3% can be considered well-conserved.
Without back-ups of seed and genetic material in genebanks, these species and their valuable traits are at risk of being lost forever. Such loss will diminish choices in the food supply and severely constrict the ability of plant breeders to adapt existing food crops to changes in the environment. Development of improved tomato varieties, for instance, relies almost entirely on the diversity safeguarded in genebanks.Without more and better germplasm conservation, breeders will lack the building blocks to craft nutritious new varieties that taste good, resist pests and diseases, and can thrive under shifting climate conditions.
Safeguarding the supporting cast
To successfully reproduce, most fruit and some vegetables need interactions with insect pollinators and other supporting organisms. Over the past 40 years, relative yields of crops that depend on insects for pollination was 13% lower than pollinator-independent crops. This “pollinator-yield gap” has been brought about by an average 45% decline in terrestrial insect populations during those four decades, the result of habitat destruction, degradation, and fragmentation. Wild species dependent on insect pollinators for cross-fertilization are also at risk of extinction.
The researchers note the necessity of protecting fruit and vegetable pollinators and seed dispersers as part of the effort to ensure diversity in food crops going forward.
Six positive trends to stem the decline
The current situation is worrying, but there is hope. The brief outlines six trends favouring better conservation and use of fruit and vegetable biodiversity: 1) greater awareness of the health benefits of diets rich in fruit and vegetables; 2) an increase in the proportion of fruit and vegetable crops in global food production; 3) a reclaiming of some underutilized and neglected species; 4) an increase in food diversity, as immigrants bring their food plants and preferences to new locales; 5) advances in biotechnology to develop new varieties; and 6) a tripling over the past 40 years of areas to protect natural habitats and traditional production systems, many managed by indigenous communities with a commitment to maintaining agrobiodiversity.
It is important that young people in particular understand why fruit and vegetable biodiversity matters to their health and economic well-being, the researchers say. School feeding and school garden programs are ways to nourish students while maintaining a range of local crops in local food systems. Chefs, cooks and food innovators promoting the taste, cultural, and health aspects of local fruit and vegetable crops can create demand to drive conservation and greater use.
A 10-year plan for protection and use
To strengthen the existing network of genebanks, fill gaps, and protect wild populations of fruit and vegetable species and their pollinators and dispersers, the researchers outlined a 10-year, USD 250 million global rescue plan for fruit and vegetable biodiversity.
Collecting wild relatives of fruit and vegetable crops as well as underutilized and neglected species to increase the breadth and depth of genebank holdings would be the initial focus, researchers say. Building genebanks in sub-Saharan Africa is another priority; the region lacks the infrastructure to document and maintain local crop diversity.
Farmers, breeders, researchers, and businesses will benefit from stronger global partnerships for the collection, conservation, and sharing of fruit and vegetable germplasm. Internationally established policies and regulations governing these actions can prevent exploitation of local communities and landscapes.
Better documentation and mapping of genetic variation in fruit and vegetable traits, especially traits related to nutritional quality, will greatly enhance development of varieties suited for specific locales and purposes, say the authors.
In situ conservation of natural habitats and traditional production systems will help maintain local fruit and vegetable crops, and stimulate evolution of new traits through natural and human selection. Policies to protect pollinators, threatened species and populations, coupled with the documentation and use of traditional knowledge, will provide a framework for conserving more plant genetic resources for food and agriculture.
Fruit conservation is a particular challenge, as many fruit species must be maintained in fields or greenhouses and specific cultivars can be maintained only through vegetative propagation. The researchers propose that national fruit conservation programs work more closely together to develop shared tissue culture and cryopreservation facilities to protect fruit diversity.
Putting ideas into action
Fruit and vegetables provide nutrition and food security, income-generating opportunities, ecosystem services, and contribute to cultural identities. Protecting these species—and by extension, our ability to nourish ourselves—demands urgent action.
The authors suggest a global team of experts from different sectors and disciplines launch an initiative under the International Treaty on Plant Genetic Resources for Food and Agriculture to better conserve, monitor, and understand the diversity of our fruit and vegetable crops.
Aligning existing conservation efforts and including measures to protect pollinators and associated organisms is key, as is improving access and benefit sharing agreements for the exchange and use of food genetic resources. Partnerships among global custodians of diversity—from individual farmers to national parks, from public breeding programs to private seed companies—will be essential to the initiative’s success.
The authors conclude with an appeal for sufficient, sustained funding to ensure a global rescue plan for fruit and vegetable diversity can shift the research and development agenda to focus on nutrition and well-being.
Examples of activities to safeguard and use fruit and vegetable biodiversity: a) Engaging young people through school-feeding programs with fresh vegetables in Burundi; b) Thai traditional meal with local bananas and a rich variety of vegetables; c) Fruit vendor in Lima, Peru with a fruit of cherimoya (Annona cherimola Mill.) of the locally-grown cumbe variety; d) Populations of the multi-purpose tree species néré (Parkia biglobosa (Jacq.) R. Br. ex G. Don) are maintained in parklands in Benin and so far do not have a genebank back-up; e) Cucumis spp. – wild cucumber from Nyika National Park delimited as a crop wild relatives (CWR) genetic reserve in Malawi as part of Darwin Initiative SADC/CWR project 26-023; f) Heirloom apple (Malus domestica (Suckow) Borkh.) trees in Yosemite National Park in the United States are maintained in situ and have a back-up in the USDA field genebank. Photos credits: a) WFP, Hugh Rutherford; b, c) WorldVeg; d) University of Abomey-Calavi, Enoch Achigan-Dako; e) Malawi PGR Centre; f) USDA, Gayle Volk.