International collaboration between collections-based institutes for halting biodiversity loss and unlocking the useful properties of plants and fungi

1Royal Botanic Gardens, Kew, Ardingly, UK 2Royal Botanic Gardens, Kew, Richmond, UK 3Gothenburg Global Biodiversity Centre and Department of Biological and Environmental Sciences, University of Gothenburg, Göteborg, Sweden 4Department of Natural Sciences, Manchester Metropolitan University, Manchester, UK 5Jardim Botânico do Rio de Janeiro, Rio de Janeiro, Brazil 6Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal 7Herbier National de Guinée, Université Gamal Abdel Nasser de Conakry, Conakry, Guinea 8Negaunee Institute for Plant Conservation Science and Action, Chicago Botanic Garden, Glencoe, IL, USA 9Global Crop Diversity Trust, Bonn, Germany 10Botanic Gardens Conservation International, Richmond, UK


| INTRODUC TI ON
There is an imperative to develop and strengthen effective national and international collaboration between collections-based institutes as a prerequisite for improving our understanding of the diversity, distribution, interactions, and threats to plants and fungi, to halt their loss and to accelerate responsible investigation of their useful properties.
Globally, these institutes house tens of millions of samples of plant and fungal biodiversity, with broad phylogenetic and geographical coverage. Significant progress has been made in aggregating globally dispersed occurrence data sets of both plants and fungi, most notably the Global Biodiversity Information Facility (GBIF Secretariat, 2019). This aggregation provides the bedrock for our exploration and understanding of plant and fungal diversity (Antonelli, Smith, & Simmonds, 2019;Bakker et al., 2020;James et al., 2018) and is a vital data resource to ensure conservation interventions are keeping pace with the increasing rate of species loss (Nic Lughadha et al., 2020). New global conservation targets have been proposed based on keeping the number of recorded extinctions of described species to less than 20 per year (Rounsevell et al., 2020). If this approach were to be adopted, the case to fund rapid acceleration in the digitization and aggregation of the globally dispersed occurrence data sets would become overwhelming.
The density of sampling is significantly greater for plants than for fungi, with collections encompassing both living (plants, seeds, cultures) and preserved (herbarium and fungarium specimen, DNA samples etc.) material. While many large collections of plant germplasm are held in the Global South, including the Consultative Group for International Agricultural Research (CGIAR) genebank collections in South America, Africa, and Asia, most of the world's larger collections of preserved specimens are housed in the Global North, and predominantly reflect historical political alignments of European and North American collectors. The past 50 years have seen a rapid increase in national collections made by a growing cadre of local botanists and mycologists (e.g., Funk, 2015;Thiers, 2020).
Rapidly improving DNA extraction technologies for preserved material (Dodsworth et al., 2019;Hart, Forrest, Nicholls, & Kidner, 2016) have significantly increased the unravelling and publication of plant and fungal phylogenies (Naranjo-Ortiz & Gabaldón, 2019;Wortley, Bennett, & Scotland, 2002). These in turn have enabled more efficient identification of potential sources of useful plant and fungal traits to support agriculture, forestry, and medicine (Grace et al., 2015). Complementing this, the growth of ex situ collections of living plants in genebanks and botanical gardens provides a significant resource to accelerate breeding programs and improve collections-based institutes provides good models for conservation; addressing species loss and improving sustainable use of plants and fungi. Nevertheless, the pressure on the planet's plant and fungal diversity is relentless. We argue that a massive increase in the accessibility of preserved and living collections of plants and fungi is required. An increased scale of responsible exploration to both conserve and unlock the useful properties of plants and fungi is needed to deliver solutions to the many global challenges facing humanity and the planet. This article explores the role of collaborations between collections-based institutes and their partners in preventing biodiversity loss and delivering sustainable development. Drawing on examples from herbaria, agricultural and wild species genebanks, mycological collections, an international NGO, and the botanic garden community, we demonstrate how collaboration improves efficiency and impact. Collaborations can be peer to peer, institutional, governmental, national, or international, they may involve work with local communities and are frequently a combination of these. We suggest the five key benefits to collaboration and show that with trust, understanding, and mutual respect, powerful and sustainable partnerships develop. Such trust and respect are hard won, but once established, sustain a high level of commitment, enable development of shared longterm visions of success, and attract diverse funding streams.

K E Y W O R D S
botanic gardens, fungarium, genebanks, herbarium, metacollection, pre-breeding, seed banks, training conservation outcomes for many of our most useful and endangered plant species (Donaldson, 2009). However, to unlock the true potential of these living ex situ plant collections, the phenotypic and genotypic characterization and evaluation of these materials needs to be accelerated (Cires et al., 2013;Tanksley & McCouch, 1997;Wood et al., 2020). This aggregation and genetic profiling of living material is driving the developing concept of the metacollection (Griffith et al., 2019). Such living plant collections afford an excellent opportunity to investigate plant-animal interactions (Baretto & Freitas, 2007;Vasconcellos & Freitas, 2007), develop propagation protocols, and better understand the potential adaptability of plants to shifting climate regimes (Seal et al., 2017). Living fungal and microbial material is also now more readily available where excellent progress in aggregating collection information and sharing accession data has been made (Ryan, McCluskey, Verkleij, Robert, & Smith, 2019).
Strengthening and rebuilding the inextricable link between people and the plants and fungi in their domain remains central for our increased understanding of the value of plant and fungal diversity to the custodians of extant natural habitats (Knapp, 2019). The Millennium Ecosystem Assessment (MEA, 2005) recognized that scientific findings and data need to be made available to all of society and that "a major obstacle to knowing (and therefore valuing), preserving, sustainably using, and sharing benefits equitably from the biodiversity of a region is the human and institutional capacity to research a country's biota." To effect change in the perceived value of biodiversity, it is not enough to simply document and describe. Local communities need to form part of collaborative arrangements and witness an improvement of their livelihoods resulting from the responsible and sustainable use of their biodiversity (Griffiths et al., 2019) and its longer-term care and repair (Reyes-García et al., 2018).
Sharing access to and information about biological collections is central to ensuring their value as a global resource for public good.
Policy frameworks are required that accelerate the exploration and sustainable use of the wealth of properties and traits which remain locked in ex situ collections and natural habitats, while ensuring benefits of this access accrue fairly to the guardians and custodians of the plant and fungal diversity from where the materials originated (Williams et al., 2020).
The following eight case studies have been chosen to demonstrate the value of strong national and international collaborations in bringing together the strengths of biologists, biological collections, new tools and technologies, and local communities. They exemplify how such collaborative efforts are required if we are to rapidly identify plant and fungal-based solutions to environmental challenges and to halt biodiversity loss. Each also demonstrates various key benefits of importance to collaboration in any sector.
These key benefits include synergy, greater efficiency, sharing resources, greater impact and leverage, and transfer of knowledge and technology.
Two examples illustrate how the aggregation of herbarium collections provides "big data" sets, strengthening national capacitythe Reflora program in Brazil and the Flora of Thailand. In Guinea, we explore how scientists working in tandem with government policy makers have secured lasting policy decisions for species, habitat, and site protection. Ensuring the role of local communities, the custodians of much of the planet's plant and fungal diversity, is presented in a study of fungal diversity in São Tomé & Príncipe. Our example from Costa Rica highlights the importance of parataxonomists in tackling large-scale identification of fungi.
Making seed material more readily available to support agriculture is explored through case studies on the Adapting Agriculture to Climate Change project and Genesys. Finally, the pressing need to characterize our living plant collections is explained through the concept of the metacollection.
The benefits, commonalities, and lessons learned from the case studies are analyzed and we identify priorities for future collaborations to accelerate the exploration of plant and fungal properties and to go some way to halt the loss of biodiversity. Bringing complementary teams together is, of course, not a new approach; this article aims to ensure that the scientific and conservation communities consider how the hard work needed to foster strong collaborative networks ultimately delivers efficiency and impact.

| Case study 1-The Reflora Program
The Reflora program (Nic Lughadha et al., 2016) was established by the Brazilian government in 2010/11 with the specific aim to "retrieve and make available images and information concerning Brazilian plants deposited chiefly in overseas herbaria," and the broader purpose "to increase knowledge and conservation of the Brazilian flora" (Canteiro et al., 2019). Two primary lines of action were envisaged: • digitization of Brazilian herbarium specimens deposited in overseas collections followed by virtual repatriation to create the Reflora Virtual Herbarium (RVH) hosted by the Rio de Janeiro Botanical Garden (JBRJ).
• a human capital mobility program designed to support research by individuals or networks involving Brazilian and non-Brazilian researchers.
Today, RVH includes 3.7 million digital specimen images sourced from some 86 herbaria. Referring to their standard Index Herbariorum code (Thiers, 2020)  A recent review (Canteiro et al., 2019) demonstrates that RVH fulfils its original purpose, having increased access to conservation-relevant information (Figure 1) for Brazil and for Latin America more broadly: half of the scientific publications citing Reflora and 81% of online survey respondents mentioned conservation-relevant outputs.
Conservation applications range from rediscovery of a rheophyte not seen for c. 170 years, which provided evidence to inform boundaries of an ecological corridor (Bove & Philbrick, 2014), to development of species checklists to inform management and monitoring in long-established Protected Areas that lacked such resources for many decades (e.g., Forzza & Lanna, 2020;Moreira et al., 2020).
Plant use by the corporate sector has been facilitated by access to authoritative data on which species are native to Brazil-vital for risk management in sourcing biodiversity inputs (Natura Cosméticos S. A., 2016) and in identification of species occurring naturally on metal-rich substrates which may have potential for revegetation following mining (Digital Plants, 2020). At the local scale, Reflora resources have been used in research documenting medicinal plant use by women resident in a settlement of descendants of freed slaves (Oliveira, 2015).
Traditionally transmitted orally, this knowledge was considered at risk due to migration and lack of interest from young people.  Other botanists from many countries continue to provide their specialist knowledge to write up accounts for families, genera, and species occurring in Thailand. The completion of the Flora of Thailand covering some 11,000 plant species, and the publication itself will represent the first of its kind in SE Asia, a region where no other modern-day Flora has, or is likely soon to be published, with the exception of the Flora of Singapore with its native flora of c.
The Flora was only possible through long standing international collaboration between European institutions, with their extensive historic collections, and a rapidly developing team of local Thai botanists. This collaborative effort and successful publishing timetable have not only fostered strong linkages with, and earned the respect of, key government departments, but also developed active plant taxonomic university groups with professors, postgraduate, and undergraduate programs in plant sciences. Fundamental to the project is increased access to collections, as well as fieldwork throughout Thailand to gap-fill taxa and regions. The Flora has benefited immensely from funding opportunities to bring Thai botanists to European institutions, especially a generous donation from the Carlsberg Foundation which recognized the benefits of the successful collaboration to date and was willing to fund the project toward its completion. In Thailand, receptive and organized in-country teams facilitated fieldwork for international visitors, and digitization of herbarium material from largely European herbaria made available on accessible online platforms is another extremely important factor in the project's success.

A National Working Group on TIPAs and Species Conservation
Action Plans has provided the first opportunity for the many academics, government staff, and NGOs working on plant conservation in Guinea to work together in a formally framed consortium (Couch et al., 2019). This close and transparent collaboration led to the government accepting the 22 TIPAs (Figure 3), identified during the project and committing to put them into legislation as part of the Protected Areas network (Couch et al., 2019).
As a result of these successes, additional funding streams have opened for on-the-ground plant conservation (e.g., a Mohamed bin Zayed Species Conservation Fund grant to conserve Guinea's Critically Endangered National Flower Vernonia djalonensis), and the partners are continuing to strengthen and expand the collaboration.
While these recent collection efforts have advanced our understanding of fungal diversity on the islands, they have not involved local stakeholders, nor contributed to mainstreaming conservation efforts. In 2019, a collaboration between the University of Coimbra, Portugal, and the islands' government through the Directorate General of Forests (DGF) was designed and funded to fill this gap (Madureira, 2018). The project moves beyond the confines of documenting fungal diversity. Using agroforestry systems in forest buffer zones of the Obô Natural Park on São Tomé, the collaboration will increase the perceived value of fungal diversity for the livelihoods of local communities from the island by piloting mushroom production units and developing markets for edible and medicinal mushrooms.
The project also includes training local farmers in the green economy and entrepreneurship, securing the conservation of fungal diversity through increased societal value.
Unlike in neighboring countries, the use of wild fungi for food and medicine is not embedded in the island's tradition. Only Volvariella sp.
("Útu" in the local dialect), collected by a few elders, and another edible mushroom, Pleurotus tuber-regium, well known and used across continental Africa, are used locally. However, during field work, several other known edible, or medicinal species with potential for domestication (e.g., Auricularia sp., Ganoderma sp.) were identified.
With a growing population and high levels of poverty (CEPF, 2015), forest resources in São Tomé are under increasing pressure. In the future, it is likely that small farmers will be forced to move to higher altitude forests where most endemic fungi have been found. The project delivered training in green economies and entrepreneurship, and through fungal domestication and providing an alternative source of income, the program will reduce the pressure of unsustainable exploitation of the remaining natural forest resource. The project delivered training in green economies and entrepreneurship, and through fungal domestication, provide an alternative source of income, the program will reduce the pressure of unsustainable exploitation of the remaining natural forest resource. The use of local isolates for production of domesticated lines will reinforce the value of local fungal diversity in the psyche of local communities leading to improved conservation outcomes. Projects such as this, which directly improve livelihoods, will go some way to reducing primary forest encroachment and the further loss of fungal diversity still largely unexplored.

| Case study 5-The Costa Rican National Fungal Inventory, integrating scientists, and parataxonomists
The Costa Rican National Fungal Inventory (1999)(2000)(2001)(2002)(2003)(2004)(2005)   Through this project, a wealth of new material has been collected and further developed that is now being introduced into breeding programs and will continue to be available to breeders for years to come under the terms and conditions of the SMTA. However, policy positions among relevant national ministries are still divergent and in flux in some cases, jeopardizing such conservation efforts. Future initiatives need to place more emphasis on making CWRs more widely recognized as global assets with appropriate mechanisms in place for their conservation and explore opportunities to influence decision makers at different levels.

| Case study 7-Agricultural genebanks and Genesys
In Genesys is a stable mechanism, managed as a core function by the Crop Trust with secure, long-term funding from the CGIAR Fund.
With an initial focus on the aggregation of the three largest data sets of plant accessions referred to above, the Genesys platform was first Genesys is a database through which national, regional, and international genebanks make available passport, characterization and evaluation data, as well as images on accessions that they con- Clearly a single plant grown in one botanic garden will rarely embody sufficient genetic diversity to fulfil a conservation need and there are also cases where the collections of a target species across many gardens will include a large proportion of clonal copies or at the very least, such a narrow genetic base that it does not in fact provide a viable breeding capacity. Collaboration across sites will identify many opportunities where combining holdings of the same species across collections will significantly increase the genetic diversity and offer the source of material for assisted reproduction of threatened species (Wood et al., 2020). Adopting these standards is the first step to forming metacollections. The metacollection requires the adherence to internationally recognized standards of data and material availability.
The Darwin Core standards have largely met this requirement for aggregation of biological observations. The documentation standards for agricultural genebanks (Alercia, Diulgheroff, & Mackay, 2015) are well documented and broadly adopted as Multi-crop Passport Descriptors.
Through its collaborative network, BGCI promotes metacollections to ensure the conservation of priority species-especially for those species whose seeds cannot be dried and frozen in conventional seed banking techniques (Fant et al., 2016;Griffith et al., 2019). While a wide range of species may be desirable for display purposes in gardens, for conservation collections, a more focused approach is needed. The aggregation of accession data for living ex situ collections needs to advance rapidly in order to identify gaps in provenance of collections. The underlying genetic characterization of different provenances will need to become a standard activity for the management of the individual accessions for priority species of conservation concern or those with the potential for sustainable use. Here, we provide the evidence that collaborative models of working offer the best chance of short-term project success and longer-term impact.

| Key benefit 1: Synergy
Designing and developing collaborative teams that bring together complementary knowledge, skills, and expertise deliver more than its individual members could.
There is an urgent need to bring together the collections, expertise, and resources frequently dispersed across countries, national institutes, and individual research groups. The existence of this disjunct means that no country can work in isolation to describe and sustainably utilize its plant resources (Grieneisen, Zhan, Potter, & Zhang, 2014 Ensuring that all the relevant partners are involved in a collaboration from inception should include not only those needed to deliver the findings, but those who will implement these findings. This is clearly evidenced in CS3 where many academics, government

| Key benefit 2: Efficiency Complex conservation projects risk being cost-inefficient if undertaken by individual researchers or organizations; collaboration
brings cost efficiencies, shared technologies, and access to local knowledge, land, and resources.

Case study 1 utilized the imaging technologies invested in by
Kew and Paris herbaria to deliver the quantity and quality of image capture of herbarium specimens housed in their collections for repatriation, while transcription of label data was undertaken at JBRJ. This was innovative for its time, achieving cost efficiencies by minimizing the number of additional staff to be employed in Europe while creating opportunities for numerous Brazil-based students to undertake data capture on a part-time basis. This in turn increased students' familiarity with the attributes and uses of herbarium material, and with their national flora. A similar model was subsequently employed in CS3, where HNG botanists transcribed label data from images working with local students and botanists, strengthening the responsibility and role of the national facility in botanical exploration. Investment may be required to achieve longer-term efficiencies. In the early stages of CS3, RBG Kew recognized that a dedicated staff member to coordinate the collaboration would ultimately deliver greater efficiency. Alongside the specific roles and responsibilities of project partners, the coordination of this new collaboration in Guinea was crucial to its success.
The hard-won trust developed between organizations over long-term collaborations can also lead to efficiencies. The deliv- CS6 provided an opportunity for national partner genebanks to establish a structure and process for collecting, conserving, and sharing CWRs. Most partners had never worked on CWRs and had to develop processes for obtaining permits, gaining clarity on the appropriate policy regimes (CBD vs. ITPGRFA) and regulatory requirements that apply to CWRs and issuing authorities, and determining the most effective and efficient way of working. The unit cost for a collection of USD1400 results from the granting of in-country funds to local genebank partners, rather than using overseas collection teams to undertake the collection program.
Genesys (CS7) provides its services in collaboration with national, regional, and international plant genetic resources databases and data services. It has therefore reduced the need for individual national agricultural genebanks to necessarily invest in the development and maintenance of high-quality data portals, while enabling those lacking resources to share their data. Project-based development of new databases often results in systems that do not have the means for maintenance and support past the project end-date.
The adoption of established standards for genebank data publication and participation in Genesys ensures that experiences and knowledge is shared and available to newcomers. In addition, this standardization of data from a wide variety of sources, with varying formats and quality, makes its use much more straightforward, saving users significant time and effort involved in data cleansing.
For many researchers it is now far more efficient to search and identify sources and provenances of material that they require by using Genesys rather than searching the websites of individual genebanks. Users will still need to contact individual genebanks for material supply but can make time-saving decisions about which genebank to approach, for example, by using material that may already be in their country, thus, avoiding often lengthy import requirements.

| Key benefit 3: Sharing resources
The trust and mutual respect developed through collaborative working helps remove barriers to sharing and aggregating specimens, data, and material held in dispersed collections.
Case study 1 and CS3 increased access to hitherto dispersed herbarium collections of Brazilian and Guinean plants though digital repatriation of specimens. CS1 developed an aggregated virtual collection and supports a national plant list (http://reflo ra.jbrj.gov. br/), resulting in increased availability of robust data, delivered in a format that now offers scientific rigor, intrinsic value, and ease of use for many audiences. CS3 produced the Guinea plants database available locally to botanists and allied users of these data.
Case study 1 also exemplifies financial resource-sharing across nations: in its first phase the international components of the program were funded mainly from Brazil, through a combination of private sector and research foundation funds. Thereafter, funding sources were Similarly, CS7 provides an established platform using consensually agreed data standards resulting in data that is compatible and simpler to utilize, enabling delivery of "big data" to a global audience.
Many examples of data aggregation and sharing of information relating to biodiversity can be found in the literature and their resulting online databases, which have vastly improved access to occurrence data for plants and fungi.
Case study 6 strengthened mechanisms for using SMTAs, to transfer collected material, giving researchers the potential to more easily access quality seed material and data on multiple occasions without the need to renegotiate terms of the supply. The

| Key benefit 4: Impact and leverage
Combining complementary skills (key benefit 1), efficiency (key benefit 2) and the trust, mutual respect, and confidence to share their resources (key benefit 3) our case studies show how collaboration can bring about long-term positive change, lead to mainstreaming of new behaviors, deliver more sustainable funding, and drive a cessation of biodiversity loss and an increase in its exploration.

Successful collaboration thus has impact and leverage beyond the initial project deliverables.
Delivering key messages to the right audience in the right way The global reach of Genesys in CS7 provides the opportunity for individual collaborators to demonstrate the value of their agriculturally important collections. This is a powerful way for smaller national genebanks to significantly enhance national and international awareness of their work on germplasm conservation, helping to leverage sustained funding and influence. Openly sharing data does not come naturally to most organizations. The very nature of data aggregation requires a high quality of data to be provided by the data donors. Genesys has provided guidance and assistance to genebanks in updating their data management practices and internal information systems, resulting in improved documentation of existing collections and the adoption of high-quality data management practices going forward. Collaborative data sharing, like that in CS8, can also lend authority and credibility to the shared data. Recommendations arising from this communal resource will have a higher profile and are more likely to be acted upon as they have the weight of multiple institutions behind them. in training or technology transfer outputs, this study illustrates that developing these qualities is a core part of the skill set required to deliver key national messages to halt biodiversity loss, raising the profile of plants and fungi in the national dialog.

| Key benefit 5: Transfer of knowledge and technologies
Case study 4 worked in partnership with other projects to identify opportunities and constraints to improving the livelihoods of local communities and provided training in the green economy and entrepreneurship to local farmers. The training has empowered local farmers and developed new local leadership to support the mainstreaming of agroforestry management models built on tradition, culture, and existing local and regional market needs.
The provision of job training and career skills to the parataxonomists and building a strong and respectful collaborative team among in-country scientists, international collaborators, and local collectors was key to success in CS5. Transfer of knowledge is not necessarily a one-way process. In addition to the flow of support to Costa Rican mycologists to enhance field collection and identification techniques, and improve collections management, there was an equally important flow of learning about Costa Rican ecology, fungi, and culture from Costa Rican mycologists, students and parataxonomists to other collaborators.
Significant technology transfer occurred throughout the CWR collecting phase of CS6 resulting in the enhanced capacity of many national partners. Some were paired with local CGIAR genebanks who provided technical support as well as the opportunity to gain relevant experiences from international partners, strengthening long-term links between partners and their regional CGIAR centers.
The multicountry nature of CS6 allowed for regional training courses such as the Seed Conservation Techniques courses delivered by the MSB. Bringing regional partners together provided opportunities to develop potential new regional collaborations, facilitated cost-effective exchange visits, and helped develop relationships that have continued after the life of the project. The Genesys project shows how beneficial it can be to deliver a system with which all collaborators and future users are comfortable, in terms of quality and usability. It demonstrates how collaborative programs and projects can strengthen the capacity of partners to undertake research on their own plant and fungal diversity, a sure way to secure value and longevity of partnerships.

| FUTURE PRIORITIE S
For collections-based organizations the accelerated sharing of collections remains a central driver for collaborative work. The eight case studies presented in this article show how international collaborations deliver benefits that are impossible to achieve when work is carried out in isolation. Our review demonstrates how effective collaborations foster long-term relationships, instill a sense of trust and mutual respect between partners which encourages and promotes the sharing of data, material, technology, tools, and knowledge: prerequisites to halting biodiversity loss and rapidly unlocking the useful properties of plants and fungi for sustainable development.
Our case studies not only demonstrate many successes, but we also recognized three areas of collaborative collection sharing where significantly more progress needs to be made. First, there is an increasing need to improve access to collection information on plants and fungi. Second, there is a pressing need to improve the access to valuable living plant and fungal material. Third, once accessed, the exploration and use of plant and fungal material (herbarium samples, seed, living plant, or fungal material) must be accelerated, in a responsible and transparent way, particularly when modern rapid screening techniques are employed to discover plant and fungal properties.

| Improving access to collection information
The digitization of specimens from the world's largest herbarium and fungarium collections requires rapid completion (Borsch et al., 2020) and digital integration, such as that articulated by the Distributed System of Scientific Collections program (DISSCo, 2020). We must address the capacity of national and regional herbaria and fungaria to completely digitize their own collections and integrate their data into international platforms. Concurrently, the data quality of these digitized records (taxonomic accuracy, inclusion of geographic information) must improve to ensure their "fitness for use" (Gaijy et al., 2013). The IT infrastructure needed to aggregate and present these data to the global conservation community must also keep pace with the inevitable increase in specimen records.
The lack of provenance information on living collections held in botanic gardens essentially makes these collections largely opaque to users. While this has been addressed for certain groups of species (see Case Study 8) there needs to be a targeted and rapid upscaling of documenting accession provenance and exploring the underlying genetic diversity across collections of both living plants and fungi.
This will allow, among other things, for an increase in their use for breeding programs supporting species conservation and contributing to the development of climate-resilient crops.

| Improving access to living material
We have already highlighted the value of increasing access to seed and other germplasm material held in genebanks (CS6 and CS7) and to living plant material of whole plants and seed from botanic gardens (CS8). Efforts to increase the exploration and use of fungi also has huge potential to support strategies against human and plant diseases, enhancing agricultural crops and forestry, food and beverages, waste disposal, and many facets of the bio-economies of Low to Middle Income Countries (LMICs; Hyde et al., 2019).
While freeze drying techniques allow for the preservation of sporing fungi for up to 50 years (Smith & Onions, 1994), cryopreservation has become the standard technology for preservation of fungi in large culture collections and should, therefore, be further expanded (Ryan et al., 2019;Ryan & Smith, 2004). This technique is also successfully used for both ectomycorrhizal and arbuscular mycorrhizal fungi (Lalaymia, Cranenbrouck, & Declerck, 2014), organisms that will play an ever-increasing role in agriculture, food security, and medicine.
There is a need to establish in-country culture collections in LMICs, although they are expensive. In addition, access to these fungal resources under the CBD and Nagoya Protocol would need to be considered. Increasing the number of fungal collections available for use should, therefore, be dependent on the development of a smaller number of well-resourced collections. As with the development of any collection facility it is important that these are provided with core financial support rather than being dependent on the vagaries of short-term funding to individual research groups. This is an example of where collaborative science may well be best grounded in countries of high income, but with a complementary onus on these facilities strengthening international collaboration, joint research programs, and technology transfer.
Codes of conduct that promote transparency between providers and recipients of plant and fungal resources, such as those promoted in the EU regulations on ABS (European Commission, 2020), should be mainstreamed among collections-based organizations worldwide.
Smart collections management systems need to track and make available the use, publications, and onward supply of any acquired material through the wide-scale application of digital object identifiers (DOIs) to individual collection accessions.
In stark contrast to the SMTA of the ITPGRFA, the more time-consuming use of bilaterally negotiated Material Transfer Agreements will benefit from the commitment to long-term collaborative programs between collections-based institutes. Such negotiated agreements need to provide accelerated and efficient access to collections from biodiverse areas of the world, and facilitate the rapid access to the advanced tools and technologies required to target and identify the many useful compounds and traits still waiting to be unlocked. Collaborations must hold firm on their adherence to the principles of the CBD and the Nagoya Protocol, protecting the rights of the guardians and custodians of that diversity and ensuring that any benefits that might accrue from its exploration and eventual use are appropriately shared.

| Accelerating responsible exploration of existing collections
The many thousands of plants and fungi used by humans are well documented (Allkin, 2017;McChesney, Venkataraman, & Henri, 2007;Ulian, Sacandé, Hudson, & Mattana, 2017). By increasing and accelerating our access to material held in global collections, the major challenges defined in the UN SDGs can be partially addressed by unlocking the many useful properties of plants and fungi (Antonelli et al., 2019). With the many tens of thousands of plant and fungal species represented in global collections yet to be explored, it is key to identify those groups of species that are most likely to contain the chemicals, properties, and traits that will prove to be useful. To this end, the establishment of phylogenetic relationships has proven a powerful toolkit (e.g., Gutaker et al., 2019;Rønsted et al., 2012). Exciting correlations between phylogeny and the production of certain useful chemical compounds are being uncovered. For example, a phylogeny of the Amaryllidoideae found strong relationships between alkaloid diversity and activity in bioassays related to the central nervous system (Rønsted et al., 2012). A recent study using historical herbarium material has traced the demographic and adaptive history of potato introduction and uncovered the likely evolutionary process of the adaptation of European potatoes to shorter day length and growing seasons (Gutaker et al., 2019). Further analysis of closely related species from existing collections and targeting of new collection priorities should follow.
It will also be important to put increased focus on population level phylogenetic sampling, since there is likely to be large intra-specific variation in relation to environmental adaptations, defense mechanisms, and other factors that may lead to different phenotypic expression (Maldonado et al., 2017). The availability and maintenance of appropriate analytical equipment for identifying useful plant compounds is largely confined to the wealthier collections-based research institutes, which will be far more readily available as a result of strong international collaboration.
In conclusion, we have highlighted the need to build and protect the trust and mutual respect within and between collaborative teams and to ensure that the use of biological collections is undertaken responsibly and with transparency. Maintaining these fundamental principles of collaboration will undoubtedly ensure sustainable management and use of our plant and fungal resources and address the challenges articulated in the SDGs.

ACK N OWLED G M ENTS
The authors and trustees of the Royal Botanic Gardens, Kew and the Kew Foundation would like to thank the Sfumato Foundation for generously funding the State of the World's Plants and Fungi project. The authors thank two anonymous reviewers whose detailed and constructive suggestions were of great assistance in improving an earlier version of this study. R.C.F. receives a research grant from the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq; 303420/2016-2), and Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado