Among the most important users of plant genetic resources, conserved predominantly in public genebanks around the world, are public and private plant breeders. Through their breeding efforts, they contribute significantly to global, regional, and local food and nutrition security. Plant breeders need genetic diversity to be able to develop competitive new varieties that are adapted to the changing environmental conditions and suit the needs of consumers. To ensure continued and timely access to the genetic resources that contain the required characteristics and traits, plant breeders established working collections with breeding materials and germplasm for the crops they were breeding. However, with the changing and increasingly more restrictive access conditions, triggered by new global legal instruments like the Convention on Biological Diversity/Nagoya Protocol and the International Treaty, plant breeders started to establish their own genebanks at the turn of the 21st century. This paper analyses the conditions that contributed to this situation as well as the historical ways that plant breeders used to acquire the germplasm they needed. Public genebanks played and continue to play a conducive role in providing genetic resources to users, including private-sector plant breeders. However, also the practices of the germplasm curators to collect and distribute germplasm were affected by the new legal framework that had been developed in global fora. It is against this background that the complementarity and collaboration between public and private sector genebanks have been assessed. Whenever possible, vegetable genetic resources and vegetable private breeding companies have been used to analyze and illustrate such collaboration. The authors look at reported successful examples of collaborative efforts and consider opportunities and approaches under which such collaboration can be established and strengthened to ensure the continued availability of the building blocks for food and nutrition security.

Genetic resources serve as the foundation of our food supply and are building blocks for the development of new crop varieties that support sustainable crop production in the face of climate change, as well as for the delivery of healthy diets to a continuously growing global population. With the encouragement of the FAO and with technical guidance and assistance from the International Board for Plant Genetic Resources (IBPGR), almost 2000 genebanks have been established worldwide for the ex situ conservation of genetic resources since the middle of the last century. The global genetic resources’ conservation and use system has evolved over several decades and presents apparent weaknesses, without a clear blueprint. Therefore, a Special Issue (SI) of Plants on ‘A Critical Review of the Current Approaches and Procedures of Plant Genetic Resources Conservation and Facilitating Use: Theory and Practice’ was initiated. This SI comprises 13 review and research papers that shed light on the history and the political dimensions of the global system; its current strengths, weaknesses, and limitations; and how the effectiveness and efficiency of the system could be improved to satisfy the germplasm users (plant breeders, researchers) and benefit consumers and society at large. This SI provides insight into new approaches and technical developments that have revolutionised ex situ conservation and the use of germplasm and related information. It also reflects on complementary conservation approaches (in situ, on-farm, home gardens) to ex situ genebanks, as well as how—through new forms of collaboration at national, regional, and global levels and through stronger links between public genebanks—synergies between the private breeding sector and botanic garden community could be achieved to strengthen the global conservation and use system. Special attention has also been given to the governance of genetic resources and access and benefit-sharing issues that increasingly hamper the needed access to a wide range of genetic resources that is essential for plant breeders to fulfil their mission.

Plant breeders develop competitive, high-yielding, resistant crop varieties that can cope with the challenges of biotic stresses and tolerate abiotic stresses, resulting in nutritious food for consumers worldwide. To achieve this, plant breeders need continuous and easy access to plant genetic resources (PGR) for trait screening, to generate new diversity that can be built into newly improved varieties. International agreements such as the Convention on Biological Diversity (CBD), the International Treaty on Plant Genetic Resources for Food and Agriculture (ITPGRFA) and the Nagoya Protocol recognised the sovereign rights of countries over their genetic resources. Under the CBD/Nagoya Protocol, countries are free to establish specific national legislations regulating germplasm access and benefit-sharing to be negotiated bilaterally. Consequently, access to PGR became increasingly restricted and cumbersome, resulting in a decrease in germplasm exchange. The ITPGRFA attempted to ease this situation by establishing a globally harmonised multilateral system (MLS). Unfortunately, the MLS is (still) restricted to a limited number of food and forage crops, with very few vegetable crops. Easy and continuous access to genetic diversity combined with equitable and fair sharing of derived benefits is a prerequisite to breeding new varieties. Facilitated access contributes to sustainable crop production and food and nutrition security; therefore, access to and, consequently, use of PGRFA needs to be improved. Thus, the authors recommend, among others, expanding the scope of the ITPGRFA to include all PGRFA and making them and all related information accessible under a Standard Material Transfer Agreement (SMTA) combined, if necessary, with a subscription system or a seed sales tax. Such a transparent, functional and efficient system would erase legal uncertainties and minimise transaction costs for conservers, curators and users of genetic resources, thus aiding plant breeders to fulfil their mission.

This Special Issue of Plants is dedicated to the eminent scientist Nikolai Ivanovich Vavilov (1887-1943) in remembrance of his 135th birthday on 25 November 1887 [...].

With the growing interest of society in healthy eating, the interest in fresh, ready-to-eat, functional food, such as microscale vegetables (sprouted seeds and microgreens), has been on the rise in recent years globally. This review briefly describes the crops commonly used for microscale vegetable production, highlights Brassica vegetables because of their health-promoting secondary metabolites (polyphenols, glucosinolates), and looks at consumer acceptance of sprouts and microgreens. Apart from the main crops used for microscale vegetable production, landraces, wild food plants, and crops' wild relatives often have high phytonutrient density and exciting flavors and tastes, thus providing the scope to widen the range of crops and species used for this purpose. Moreover, the nutritional value and content of phytochemicals often vary with plant growth and development within the same crop. Sprouted seeds and microgreens are often more nutrient-dense than ungerminated seeds or mature vegetables. This review also describes the environmental and priming factors that may impact the nutritional value and content of phytochemicals of microscale vegetables. These factors include the growth environment, growing substrates, imposed environmental stresses, seed priming and biostimulants, biofortification, and the effect of light in controlled environments. This review also touches on microgreen market trends. Due to their short growth cycle, nutrient-dense sprouts and microgreens can be produced with minimal input; without pesticides, they can even be home-grown and harvested as needed, hence having low environmental impacts and a broad acceptance among health-conscious consumers.

EDITORIAL article Front. Plant Sci., 21 September 2022Sec. Crop and Product Physiology Volume 13 - 2022 | https://doi.org/10.3389/fpls.2022.1033236

The history of ex situ conservation is relatively short, not more than a century old. During the middle of last century, triggered by the realization that genetic erosion was threatening the existing landraces and wild relatives of the major food crops, global efforts to collect and conserve the genetic diversity of these threatened resources were initiated, predominantly orchestrated by FAO. National and international genebanks were established to store and maintain germplasm materials, conservation methodologies were created, standards developed, and coordinating efforts were put in place to ensure effective and efficient approaches and collaboration. In the spontaneously developing global conservation system, plant breeders played an important role, aiming at the availability of genetic diversity in their breeding work. Furthermore, long-term conservation and the safety of the collected materials were the other two overriding criteria that led to the emerging international network of ex situ base collections. The political framework for the conservation of plant genetic resources finds its roots in the International Undertaking of the FAO and became 'turbulent rapid' with the conclusion of the Convention on Biological Diversity. This paper reviews the history of the global ex situ conservation system with a focus on the international network of base collections. It assesses the major ex situ conservation approaches and methods with their strengths and weaknesses with respect to the global conservation system and highlights the importance of combining in situ and ex situ conservation.

In this paper, we review gene bank operations that have an influence on the global conservation system, with the intention to identify critical aspects that should be improved for optimum performance. We describe the role of active and base collections and the importance of linking germplasm conservation and use, also in view of new developments in genomics and phenomics that facilitate more effective and efficient conservation and use of plant agrobiodiversity. Strengths, limitations, and opportunities of the existing global ex situ conservation system are discussed, and measures are proposed to achieve a rational, more effective, and efficient global system for germplasm conservation and sustainable use. The proposed measures include filling genetic and geographic gaps in current ex situ collections; determining unique accessions at the global level for long-term conservation in virtual base collections; intensifying existing international collaborations among gene banks and forging collaborations with the botanic gardens community; increasing investment in conservation research and user-oriented supportive research; improved accession-level description of the genetic diversity of crop collections; improvements of the legal and policy framework; and oversight of the proposed network of global base collections.

Malnutrition, comprising undernutrition, micronutrient deficiency, and overnutrition, is more widespread than hunger per se and affects most nations around the globe. The diversity and the quality of food produced and consumed are decisive factors when addressing the triple burden of malnutrition. In this context, fruit, vegetables, and nuts are increasingly moving into the focus of the nutrition community. Agricultural policies and investments in agriculture are predominantly focused on staple food production, neglecting the economic and nutritional potential of fruit and vegetables. While global vegetables are well represented in genebanks around the globe, this is much less the case for traditional vegetables. Collecting efforts in hotspots of vegetable diversity in Africa and Asia are required to conserve this germplasm before it is being replaced by modern varieties. Home gardens, community seedbanks, and variety introduction through vegetable seed kits are ways how genebanks can link with the farming community to strengthen the informal seed sector. This in turn may result in more diverse production systems and increased consumption of fruit and vegetables. In the formal seed sector, vegetable breeders need access to a wide diversity of genetic resources, predominantly farmers' varieties, landraces, and crop wild relatives. Genomics-assisted breeding is increasingly facilitating the introgression of favorable genes and quantitative trait loci (QTLs) with complex inheritance patterns from wild species into cultigens. This will lead to wider use of crop wild relatives in the development of resilient cultivars.

Plant biodiversity is the foundation of our present-day food supply (including functional food and medicine) and offers humankind multiple other benefits in terms of ecosystem functions and resilience to climate change, as well as other perturbations. This Special Issue on ‘Plant Biodiversity and Genetic Resources’ comprises 32 papers covering a wide array of aspects from the definition and identification of hotspots of wild and domesticated plant biodiversity to the specifics of conservation of genetic resources of crop genepools, including breeding and research materials, landraces and crop wild relatives which collectively are the pillars of modern plant breeding, as well as of localized breeding efforts by farmers and farming communities. The integration of genomics and phenomics into germplasm and genebank management enhances the value of crop germplasm conserved ex situ, and is likely to increase its utilization in plant breeding, but presents major challenges for data management and the sharing of this information with potential users. Furthermore, also a better integration of in situ and ex situ conservation efforts will contribute to a more effective conservation and certainly to a more sustainable and efficient utilization. Other aspects such as policy, access and benefit-sharing that directly impact the use of plant biodiversity and genetic resources, as well as balanced nutrition and enhanced resilience of production systems that depend on their increased use, are also being treated. The editorial concludes with six key messages on plant biodiversity, genetic erosion, genetic resources and plant breeding, agricultural diversification, conservation of agrobiodiversity, and the evolving role and importance of genebanks.

Okra and water spinach are traditional vegetables that are vital for healthy diets. Major variations in germination response have been observed among genebank entries. This study was undertaken to elucidate the effect of various seed treatments on the germination of fresh and stored seed of okra and water spinach. Freshly harvested fruits of two okra and two water spinach accessions with contrasting geographical origin and breeding status were dried in a screenhouse prior to manual seed extraction and cleaning. Cleaned seeds were dried to 6% seed moisture content in a dehumidified drying room. Various seed treatments were conducted after a 6-month storage period at 5oC and -15oC. Our studies confirmed previous results that both okra and water spinach are difficult to germinate and to obtain good field establishment due to physical, seed coat-imposed dormancy. Moreover, significant genotypic variation among genebank entries/cultivars was found for both crops, making germination response difficult to predict. Improved varieties showed much better germination response than landraces and did not require seed treatments for satisfactory germination. Hydropriming, i.e. soaking of seed in water for 24 hours, did not have an impact on seed germination. Partial removal of the seed coat, followed by 24 hours soaking in water consistently resulted in high germination percentages (>80%) of genotypes of both crops that had not undergone dedicated breeding (landraces), under laboratory and screenhouse conditions and during two subsequent growing seasons. When distributing seed samples of semi-domesticated accessions or landraces, genebanks should advise seed recipients that scarification methods may be necessary to obtain satisfactory seed germination and field establishment.

Vegetables can be defined as the edible portion of usually herbaceous plants. Vegetables comprise a broad range of genera and species and are an important component of a healthy diet, providing vitamins, antioxidants, minerals, fiber, amino acids and other health-promoting compounds for nutritional security. This chapter provides an overview of global vegetable production and highlights the role of genetic resources for sustainable production systems. It focuses on ex situ and in situ conservation of vegetable genetic resources and related portals to access information on global germplasm holdings, including trait mining portals. The chapter highlights crop wild relatives (CWR) and landraces. CWR are important for maintaining genetic diversity and preventing crop losses, which may have grave consequences for food and nutrition security. The diversity of plant genetic resources provides farmers and plant breeders with the necessary genetic base to enhance crop performance of cultivated varieties under climate change scenarios.

This review article gives an account of the origin, domestication, and dispersal of taro, a staple food crop in many countries in the humid tropics and subtropics. Genetic diversity studies indicated that distinct gene pools exist in all the regions where taro may be naturally distributed-the Indian subcontinent, China, Southeast Asia, and in Oceania. The Asian gene pool presented the highest genetic diversity. Diploid taro is prevalent in the Pacific Islands, while both diploids and triploids are found in mainland Asia. Triploids are thought to provide better adaptability and enhanced hardiness to higher altitudes and latitudes where sexual reproduction is not viable. The Centre for Pacific Crops and Trees (CePaCT) conserves in vitro close to 70% of the taro genetic resources held ex situ and is therefore considered the world center for taro genetic resources. Phytophthora colocasiae or taro leaf blight (TLB) is the most severe disease of taro' causing 25%-50% yield losses and postharvest decay of corms. The CePaCT genebank supported the participatory TLB breeding program in Samoa through the provision of diverse taro germplasm from the Asian gene pool. However, CePaCT not only serves taro producers in the Pacific but also shares new allelic diversity of taro globally. More recent distributions of taro genetic diversity to West and Central Africa were in response to an outbreak and spread of TLB in West Africa. Global dissemination of taro genetic diversity is assisting producer countries in the process of adaptation to emerging biotic and abiotic stresses, exacerbated by climate change.

Malnutrition is widespread and affects about one-third of humanity. Increasing production and consumption of vegetables is an obvious pathway to improve dietary diversity, nutrition and health. This chapter analyses how climate change is affecting vegetable production, with a special focus on the spread of insect pests and diseases. A thorough literature review was undertaken to assess current global vegetable production, the factors that affect the spread of diseases and insect pests, the implications caused by climate change, and how some of these constraints can be overcome. This study found that climate change combined with globalization, increased human mobility, and pathogen and vector evolution has increased the spread of invasive plant pathogens and other species with high fertility and dispersal. The ability to transfer genes from wild relatives into cultivated elite varieties accelerates the development of novel vegetable varieties. World Vegetable Center breeders have embarked on breeding for multiple disease resistance against a few important pathogens of global relevance and with large evolutionary potential, such as chili anthracnose and tomato bacterial wilt. The practical implications of this are that agronomic practices that enhance microbial diversity may suppress emerging plant pathogens through biological control. Grafting can effectively control soil-borne diseases and overcome abiotic stress. Biopesticides and natural enemies either alone or in combination can play a significant role in sustainable pathogen and insect pest management in vegetable production system. This chapter highlights the importance of integrated disease and pest management and the use of diverse production systems for enhanced resilience and sustainability of highly vulnerable, uniform cropping systems.

Moringa (Moringa oleifera) is a perennial softwood vegetable tree widely grown in the tropics of Asia, Latin America, and sub-Saharan Africa. Most parts of the tree are edible. The leaves and flowers are eaten as salad, as cooked vegetables, added to soups and sauces, or used to make tea. The young, tender pods - known as drumsticks - are highly valued as a vegetable in Asia. Moringa is nutrient-dense and rich in essential micronutrients and vitamins as well as antioxidants and bioavailable iron. According to data available at AVRDC's Nutrition Lab, moringa exceeds the micronutrient content of tomato, based on 100 g FW, by a factor of 9 to 38: beta-carotene content - 15.28 mg (x38); vitamin C - 459 mg (x24); vitamin E - 25.25 mg (x22); iron - 10.09 mg (x19); folates - 93 mu g (x19); antioxidant activity - 2858 TE (x9). Moringa is also rich in protein: 100 g of fresh moringa leaves contain 9.4 g of protein comprising all essential amino acids in nutritionally balanced proportions. Boiling fresh moringa leaves and dried powder in water enhances aqueous antioxidant activity and increases bioavailable iron by a factor of 3. Dried leaf powder is processed into moringa capsules and used as a dietary supplement. Depending on the genotype, leaf fresh weight of the first two harvests ranges from 560 g to 2.3 kg plant(-1). Total fresh matter yield at first harvest (leaves and young shoots) depends on plant density and varies from 19.6 to 78 t ha(-1) with a plant density of 95,000 and 1 million plants, respectively. Moringa has great potential to generate income for smallholder farmers and to enhance environmental services by controlling soil and wind erosion, and by providing shade and clean water. Given its multiple uses and wide range of adaptability, moringa is an ideal crop for sustainable food production.

In Sustainable Development Goal 2, the UN has sought to abolish both hunger and malnutrition by ensuring the continuous supply of sufficient, wholesome food enabling people to shift towards adopting healthier, well-balanced diets. In addition, it calls for the establishment of new ways to reduce current food wastage, farming in a manner which conserves biodiversity and environmental services, increases enterprise profitability through new business models and empowers women. Finally, it seeks for governments to create coherent policies at all levels allowing these positive changes in farming systems to take place in every country. Moringa will play a key role in helping these desirable visions be attained. Moringa is a reasonably unique species as its fresh leaves and pods are both edible and extremely micronutrient dense. Its dried leaves are a good micronutrient source in food fortification for chronically underfed and malnourished children. It is a fast growing, productive tree that adapts well to a range of environments, especially in hot, semi-arid regions and is, thus, a climate-resilient crop. It grows well in a wide range of production systems from a densely planted green vegetable repetitively harvested crop, to a fully-grown tree crop which can be harvested periodically when needed. Use of this diversity of production systems in specialized environments can promote in-situ germplasm conservation, soil conservation, sustainable production systems, enhanced profitability and a continuous source of vitamins and minerals for smallholder farm families, and often - all of these attributes together. This species is thus a boon to women small-holders as it enables them to better provide their children with highly nutritious food direct from the family home garden or by procurement in the local market. Likewise, its good productivity and wide range of adaptability helps to develop resilience in farm enterprises and to ensure better enterprise profitability and sustainability.