plants
Article
Adapting Agriculture to Climate Change: A Synopsis of
Coordinated National Crop Wild Relative Seed Collecting
Programs across Five Continents
Ruth J. Eastwood 1,*,† , Beri B. Tambam 2 , Lawrence M. Aboagye 3, Zeynal I. Akparov 4 ,
Sunday E. Aladele 5, Richard Allen 1, Ahmed Amri 6, Noelle L. Anglin 7,‡, Rodolfo Araya 8,
Griselda Arrieta-Espinoza 9, Aydin Asgerov 4, Khadijah Awang 10, Tesfaye Awas 11,
Ana Maria Barata 12, Samuel Kwasi Boateng 3, Joana Magos Brehm 13,§ , Joelle Breidy 14,
Elinor Breman 1 , Arturo Brenes Angulo 15, Marília L. Burle 16 , Nora P. Castañeda-Álvarez 2,
Pedro Casimiro 17,‖, Néstor F. Chaves 8 , Adelaide S. Clemente 13,‖, Christopher P. Cockel 1,
Alexandra Davey 18,¶, Lucía De la Rosa 19, Daniel G. Debouck 20, Hannes Dempewolf 2,
Hiba Dokmak 14, David Ellis 21, Aisyah Faruk 1 , Cátia Freitas 22, Sona Galstyan 23,
Rosa M. García 19 , Krishna H. Ghimire 24 , Luigi Guarino 2, Ruth Harker 25,¶,
Roberta Hope 18,¶, Alan W. Humphries 26 , Nelissa Jamora 2 , Shakeel Ahmad Jatoi 27 ,
Manana Khutsishvili 28, David Kikodze 28, Angelos C. Kyratzis 29, Pedro León-Lobos 30 ,
Udayangani Liu 1 , Ram P. Mainali 24 , Afig T. Mammadov 4 ,
Norma C. Manrique-Carpintero 21 , Daniele Manzella 31,**, Mohd Shukri Mat Ali 10,
Marcelo B. Medeiros 16 , María A. Mérida Guzmán 32, Tsira Mikatadze-Pantsulaia 33,
El Tahir Ibrahim Mohamed 34, Álvaro Monteros-Altamirano 35 , Aura Morales 36,
Citation: Eastwood, R.J.; Tambam, Jonas V. Müller 1, John W. Mulumba 37, Anush Nersesyan 23 , Humberto Nóbrega 38,
B.B.; Aboagye, L.M.; Akparov, Z.I.; Desterio O. Nyamongo 39, Matija Obreza 2, Anthony U. Okere 5, Simone Orsenigo 40 ,
Aladele, S.E.; Allen, R.; Amri, A.; Fernando Ortega-Klose 30, Astghik Papikyan 23 , Timothy R. Pearce 1 ,
Anglin, N.L.; Araya, R.; Miguel A. A. Pinheiro de Carvalho 38,41 , Jaime Prohens 42 , Graziano Rossi 40 ,
Arrieta-Espinoza, G.; et al. Adapting Alberto Salas 21, Deepa Singh Shrestha 24, Sadar Uddin Siddiqui 27, Paul P. Smith 43 ,
Agriculture to Climate Change: A Diego A. Sotomayor 44,45 , Marcelo Tacán 35 , César Tapia 35, Álvaro Toledo 46,
Synopsis of Coordinated National Jane Toll 2, Dang Toan Vu 47 , Tuong Dang Vu 47 , Michael J. Way 1 , Mariana Yazbek 6,
Crop Wild Relative Seed Collecting Cinthya Zorrilla 48,†† and Benjamin Kilian 2
Programs across Five Continents.
Plants 2022, 11, 1840. https://
doi.org/10.3390/plants11141840 1 Royal Botanic Gardens, Kew, Wakehurst, Ardingly, Haywards Heath RH17 6TN, UK; cuna44@me.com (R.A.);
e.breman@kew.org (E.B.); c.cockel@kew.org (C.P.C.); a.faruk@kew.org (A.F.); u.liu@kew.org (U.L.);
Academic Editors: Andreas W. Ebert, j.mueller@kew.org (J.V.M.); t.pearce@kew.org (T.R.P.); m.way@kew.org (M.J.W.)
Igor G. Loskutov and 2 Global Crop Diversity Trust, Platz der Vereinten Nationen 7, 53113 Bonn, Germany;
Axel Diederichsen beri.bonglim@croptrust.org (B.B.T.); nora.castaneda@croptrust.org (N.P.C.-Á.);
hannes.dempewolf@croptrust.org (H.D.); luigi.guarino@croptrust.org (L.G.);
Received: 9 June 2022
nelissa.jamora@croptrust.org (N.J.); matija.obreza@croptrust.org (M.O.); janetoll10@gmail.com (J.T.);
Accepted: 29 June 2022 benjamin.kilian@croptrust.org (B.K.)
Published: 13 July 2022 3 CSIR—Plant Genetic Resources Research Institute, Bunso P.O. Box 7, Ghana;
aboagyelawrencemisa@yahoo.com (L.M.A.); bkwasi16@yahoo.com (S.K.B.)
Publisher’s Note: MDPI stays neutral 4 Genetic Resources Institute of Azerbaijan NAS, 155 Azadlig Avenue, Baku AZ1106, Azerbaijan;
with regard to jurisdictional claims in
akparov@yahoo.com (Z.I.A.); aydin.asgerov@genres.science.az (A.A.); afig.mammadov@gmail.com (A.T.M.)
published maps and institutional affil- 5 National Centre for Genetic Resources and Biotechnology, Moor Plantation, Ibadan PMB 5382, Nigeria;
iations. saladele6083@gmail.com (S.E.A.); okere.anthony@nacgrab.gov.ng (A.U.O.)
6 The International Center for Agricultural Research in the Dry Areas, Dalia Bldg, 2nd Floor Bashir El Kassar
Street Verdun, Beirut 1108-2010, Lebanon; a.amri@cgiar.org (A.A.); m.yazbek@cgiar.org (M.Y.)
7 USDA ARS Small Grains and Potato Germplasm Research, 1691 S 2700 W, Aberdeen, ID 83210, USA;
Copyright: © 2022 by the authors. noelle.anglin@usda.gov
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This article is an open access article Church of Barrio San José, La Garita, Alajuela 183-4050, Costa Rica; avillalo2005@hotmail.com (R.A.);
nestor.chaves@ucr.ac.cr (N.F.C.)
distributed under the terms and 9 Centro de Investigación en Biología Celular y Molecular, Universidad de Costa Rica, Ciudad de la
conditions of the Creative Commons
Investigación—C.P., San José 11501-2050, Costa Rica; griselda.arrieta@ucr.ac.cr
Attribution (CC BY) license (https:// 10 Malaysian Agricultural Research and Development Institute (MARDI), Persiaran MARDI-UPM,
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Plants 2022, 11, 1840. https://doi.org/10.3390/plants11141840 https://www.mdpi.com/journal/plants
Plants 2022, 11, 1840 2 of 18
11 Ethiopian Biodiversity Institute, Comoros Street, Yeka Subcity, Addis Ababa P.O. Box 30726, Ethiopia;
tesfayeawas@gmail.com
12 Banco Português de Germoplasma Vegetal, INIAV, Quinta de S. José, São Pedro de Merelim,
4700-859 Braga, Portugal; ana.barata@iniav.pt
13 Jardim Botânico, Museu Nacional de Historia Natural e da Ciência, Universidade de Lisboa,
R. da Escola Politécnica 56, 1250-102 Lisboa, Portugal; joanabrehm@gmail.com (J.M.B.);
maclemente@fc.ul.pt (A.S.C.)
14 Lebanese Agricultural Research Institute, Tal Amara, Rayak P.O. Box 287, Lebanon; jbreidy@lari.gov.lb (J.B.);
hibadokmak@gmail.com (H.D.)
15 Centro de Investigaciones Agronómicas, Universidad de Costa Rica, San José 11501-2060, Costa Rica;
arturo.brenes@ucr.ac.cr
16 Embrapa Genetic Resources and Biotechnology, Parque Estação Biológica, Av. W5 Norte (Final),
Brasília 70770-917, DF, Brazil; marilia.burle@embrapa.br (M.L.B.); marcelo.brilhante@embrapa.br (M.B.M.)
17 Direção Regional do Ambiente e Alterações Climáticas, Rua Cônsul Dabney, Colónia Alemã, Apartado 140,
9900-014 Horta, Portugal; pedro.gp.casimiro@azores.gov.pt
18 Fauna & Flora International, The David Attenborough Building, Pembroke Street, Cambridge CB2 3QZ, UK;
alickydavey@gmail.com (A.D.); robertahope@hotmail.co.uk (R.H.)
19 Plant Genetic Resources Centre, National Institute for Agricultural and Food Research and
Technology (CRF-INIA), CSIC, Finca La Canaleja, A2 km 36, 28800 Alcalá de Henares, Spain;
lucia.delarosa@inia.csic.es (L.D.l.R.); rosamaria.garcia@inia.csic.es (R.M.G.)
20 Alliance Bioversity International Center of Tropical Agriculture, km 17, Recta Cali-Palmira, Apartado Aéreo
6713, Cali 763537, Colombia; danieldebouck@outlook.com
21 International Potato Center, Avenida La Molina 1895, La Molina, Lima 15023, Peru;
davedellis07@gmail.com (D.E.); nmanrique@agrosavia.co (N.C.M.-C.); ricesalas@gmail.com (A.S.)
22 Banco de Sementes dos Açores, Rua de São Lourenço, nº 23 Flamengos, 9900-401 Horta, Portugal;
catia.f.freitas@azores.gov.pt
23 Institute of Botany after A. Takhtajyan of the National Academy of Sciences of the Republic of Armenia,
Acharyan Street 1, Yerevan 0040, Armenia; galstyans@ymail.com (S.G.); annersesyan1@gmail.com (A.N.);
papikyanastghik@gmail.com (A.P.)
24 National Agriculture Genetic Resources Centre, Nepal Agricultural Research Council (NARC), Khumaltar,
Lalitpur P.O. Box. 3605, Nepal; ghimirekh@gmail.com (K.H.G.); mainalism.rp@gmail.com (R.P.M.);
deesshrestha@gmail.com (D.S.S.)
25 Natural England, Foss House, Kings Pool, 1-2 Peasholme Green, York YO1 7PX, UK; ruthharker@gmail.com
26 South Australian Research and Development Institute, Plant Research Centre, Waite Precinct, Gate 2b Hartley
Grove, Urrbrae, SA 5064, Australia; alan.humphries@sa.gov.au
27 Bio-Resources Conservation Institute, National Agricultural Research Centre, Park Road,
Islamabad 45500, Pakistan; sajatoi@gmail.com (S.A.J.); ssadar2@gmail.com (S.U.S.)
28 Institute of Botany, Ilia State University, 1 Botanikuri Str., 0105 Tbilisi, Georgia;
mananakhuts@yahoo.com (M.K.); kikodze.david@dzelkva.com (D.K.)
29 Agricultural Research Institute, Athalassa, P.O. Box 22016, Nicosia 1516, Cyprus; a.kyratzis@ari.gov.cy
30 Instituto de Investigaciones Agropecuarias, Fidel Oteíza 1956, Pisos 12, Providencia, Santiago 8320000, Chile;
pleon@inia.cl (P.L.-L.); fortega@inia.cl (F.O.-K.)
31 Independent Consultant, Phoenix, AZ, USA; daniele.manzella@fao.org
32 Institute of Agricultural Science and Technology, km 21.5 Highway to the Pacific, Bárcena,
Villa Nueva, Guatemala; mmerida@icta.gob.gt
33 National Botanical Garden of Georgia, 1 Botanicuri Street, 0105 Tbilisi, Georgia; tsirapantsu@yahoo.com
34 Agricultural Plant Genetic Resources Conservation and Research Centre, Agricultural Research Corporation,
Wad Medani P.O. Box 126, Sudan; eltahir81@yahoo.com
35 Instituto Nacional de Investigaciones Agropecuarias, Avenida Amazonas y Eloy Alfaro, Edificio MAG,
Cuarto Piso, Quito 170518, Ecuador; alvaro.monteros@iniap.gob.ec (Á.M.-A.);
marcelo.tacan@iniap.gob.ec (M.T.); cesar.tapia@iniap.gob.ec (C.T.)
36 Centro Nacional de Tecnología “Enrique Álvarez Córdova”, km 33.5 Carretera a Santa Ana, San Andrés,
Ciudad Arce, La Libertad, El Salvador; aurajdb@yahoo.com
37 Plant Genetic Resources Centre, National Agricultural Research Organization, Plot 2-4 Berkeley Road,
Entebbe P.O. Box 40, Uganda; jwmulumba@yahoo.com
38 ISOPlexis—Centro de Agricultura Sustentável e Tecnologia Alimentar, Universidade da Madeira, Campus da
Penteada, 9020-105 Funchal, Portugal; miguel.carvalho@staff.uma.pt (M.A.A.P.d.C.);
humberto_nobrega@yahoo.com (H.N.)
39 Kenya Agricultural and Livestock Research Organisation, Genetic Resources Research Institute,
Nairobi P.O. Box 30148-00100, Kenya; desterio.nyamongo@kalro.org
40 Department of Earth and Environmental Sciences, Pavia University, Via Sant’Epifanio 14, 27100 Pavia, Italy;
simone.orsenigo@unipv.it (S.O.); graziano.rossi@unipv.it (G.R.)
41 CITAB—Centro de Investigação e Tecnologias Agroambientais e Biológicas, 5001-801 Vila Real, Portugal
Plants 2022, 11, 1840 3 of 18
42 Institute for the Conservation and Improvement of Valencian Agrodiversity (COMAV),
Universitat Politècnica de València, Camino de Vera 14, 46022 Valencia, Spain; jprohens@btc.upv.es
43 Botanic Gardens Conservation International, Descanso House, 199 Kew Road, Richmond TW9 3BW, UK;
paul.smith@bgci.org
44 Subdirección de Recursos Genéticos, Instituto Nacional de Innovación Agraria, Av. La Molina 1981,
La Molina, Lima 15024, Peru; dsotomayor@lamolina.edu.pe
45 Facultad de Ciencias, Universidad Nacional Agraria La Molina, Av. La Molina s/n, La Molina,
Lima 15024, Peru
46 Food and Agriculture Organization of the United Nations, Viale delle Terme di Caracalla s/n,
00153 Roma, Italy; alvaro.toledo@fao.org
47 Plant Resources Center, Vietnam Academy of Agricultural Sciences, An Khanh, Hoai Duc,
Ha Noi 131000, Vietnam; vdtoannga2003@gmail.com (D.T.V.); tuongvd.prc@gmail.com (T.D.V.)
48 Joint FAO/IAEA Centre of Nuclear Techniques in Food and Agriculture, Plant Breeding and Genetics Section,
1400 Vienna, Austria; cinzocis@gmail.com
* Correspondence: ruthbythedowns@gmail.com
† Current address: Independent Researcher, Hassocks, Brighton BN6 8PZ, UK.
‡ Current address: International Potato Center, Avenida La Molina 1895, La Molina, Lima 15023, Peru.
§ Current address: School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
‖ Current address: cE3c Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências,
Universidade de Lisboa, C2, Campo Grande, 1749-016 Lisboa, Portugal.
¶ Current address: Royal Botanic Gardens, Kew, Wakehurst, Ardingly, Haywards Heath RH17 6TN, UK.
** Current address: Food and Agriculture Organization of the United Nations, 00153 Rome, Italy.
†† Current address: Subdirección de Recursos Genéticos, Instituto Nacional de Innovación Agraria,
Av. La Molina 1981, La Molina, Lima 15024, Peru.
Abstract: The Adapting Agriculture to Climate Change Project set out to improve the diversity,
quantity, and accessibility of germplasm collections of crop wild relatives (CWR). Between 2013 and
2018, partners in 25 countries, heirs to the globetrotting legacy of Nikolai Vavilov, undertook seed
collecting expeditions targeting CWR of 28 crops of global significance for agriculture. Here, we
describe the implementation of the 25 national collecting programs and present the key results. A total
of 4587 unique seed samples from at least 355 CWR taxa were collected, conserved ex situ, safety
duplicated in national and international genebanks, and made available through the Multilateral
System (MLS) of the International Treaty on Plant Genetic Resources for Food and Agriculture (Plant
Treaty). Collections of CWR were made for all 28 targeted crops. Potato and eggplant were the most
collected genepools, although the greatest number of primary genepool collections were made for
rice. Overall, alfalfa, Bambara groundnut, grass pea and wheat were the genepools for which targets
were best achieved. Several of the newly collected samples have already been used in pre-breeding
programs to adapt crops to future challenges.
Keywords: plant genetic resources; crop wild relatives; seed collection; ex situ conservation; food security
1. Introduction
Ensuring physical and economic access to sufficient, safe, and nutritious food—food
security—is a challenge for sustainable agriculture as much today as in the days of Nikolai
Vavilov, if not more so. Then as now, numerous factors contribute to the food security
challenge, including population growth, income inequality, population distribution, dietary
expectations, decreasing land and water for agriculture, and pests and disease threats [1]. In
addition, global climate change is predicted to have adverse effects on food production [2,3].
Crop breeding can help to enhance food security, but access to, and sharing of, ge-
netic resources will be required alongside improved strategies and technologies [4]. The
International Treaty on Plant Genetic Resources for Food and Agriculture (hereinafter, the
Plant Treaty) supports the conservation and sustainable use of plant genetic resources for
research and breeding and the fair and equitable sharing of benefits arising from their
use [5]. It recognizes the interdependence of countries on crop diversity and has established
Plants 2022, 11, 1840 4 of 18
a Multilateral System (MLS) for Access and Benefit Sharing to ensure that genetic resources
of 64 crops are globally accessible in a facilitated manner for food security.
Crop wild relatives (CWR) are genetic resources considered within the Plant Treaty.
Although exact definitions vary [6], it is generally agreed that CWR are the closely related
species of crops that are found growing in natural habitats and can exchange genetic mate-
rial with cultivated plants. As wild plants thriving in isolated, extreme, or heterogeneous
environments, CWR are expected to have locally adapted alleles that are no longer found in
cultivated crops [7]. Therefore, CWR are widely considered to be a valuable source of useful
traits and genetic diversity for crop improvement [7–11]. The need to widen the diversity
of genepools is particularly evident when large areas planted with uniform, genetically
susceptible plants are devastated by outbreaks of pests and diseases [7]; for example, corn
leaf blight in the United States in the 1970s [12] and taro leaf blight in the Pacific islands in
the 1990s [13]. Tyack and Dempewolf [14] summarized the findings of several studies that
estimated the economic value of CWR in crop improvement. The annual benefits attributed
to CWR range from USD 8 million to 165 billion, for activities that include providing useful
alleles for crop improvement and contributing to the global economy.
Although CWR have been relatively neglected for decades [15], their potential was
highlighted by Vavilov, and their use in breeding has been increasing since the 1980s [16].
The use of CWR is widespread and well-established for crops such as barley [17], potato [18],
wheat [19–22] and rice [23–25] and developing for others such as alfalfa [26], carrot [27],
chickpea [28], eggplant [29,30], finger millet [31], grass pea [32] and sorghum [33,34]. The
starting point for use is viable hybridization between the crop and a wild relative. Using
traditional breeding methods, it is easiest to make these crosses with species in the so-
called primary genepool. It becomes increasingly difficult, often requiring technological
intervention, to make crosses with species in the secondary and tertiary genepools. For
some crops, even more distant relatives can potentially produce viable crosses [35] and
modern methods are opening up access to hitherto unexplored diversity.
Diverse and representative collections of CWR are required to enable research on
crop origins and domestication (as pioneered by Vavilov), to search for specific adaptive
solutions and to provide sufficient material for base-broadening programs [36–38]. In the
past, the use of CWR in plant breeding largely focused on resistance to biotic stresses,
particularly pest and disease resistance [16]. However, there is now greater recognition of
the need to prepare climate-ready varieties that are adapted to local abiotic conditions [10].
“Breeding for climate change” means the improvement of crops through the targeted
selection of traits such as tolerance to drought, heat, and salinity, although it may also refer
to changes in morphology to improve agronomic processes [11,39,40]. The physiological
solutions to adapt to, and mitigate the effects of, climate change may well differ among
different crops and regions.
For the potential of CWR to be fully realized in crop breeding, they must be read-
ily available in genebanks and adequately characterized. Responding to this challenge,
the global initiative “Adapting Agriculture to Climate Change”, hereinafter the CWR
Project [41], was launched with funding from the Norwegian government. The first steps
of the CWR Project were the compilation of the Harlan and de Wet CWR Inventory [42]
and a global gap analysis [43,44]. These tools allowed the identification and prioritization
of the ex situ conservation needs of CWR on a global scale. The same data were also used
to investigate in situ conservation priorities for CWR [45]. The project then implemented a
coordinated collecting program in 25 countries, sampling the CWR of 28 crops of major
global importance; all partner countries agreed to placing the resulting diversity into the
MLS of the Plant Treaty.
Collecting CWR for conservation and use in breeding is not a new idea [46] but the
large scale of the task is now apparent [43] and the urgency to breed climate-ready crops is
unprecedented [47]. In addition, the environments where many CWR grow are vulnerable
to changes in climate and land use [48]. Securing CWR ex situ is required to prevent
genetic erosion, including local extinction. The CWR Project highlights the importance
Plants 2022, 11, 1840 5 of 18
of international coordination and collaboration in the conservation and use of CWR for
research and breeding. This project involves a wide range of partners from all around the
world and is motivated by scientifically informed priority setting. The CWR Project has
followed in the footsteps of Vavilov, carrying out seed collecting expeditions across five
continents [38]. A review of a partial dataset of collections made during this project has
been published [49], but here we evaluate the complete collecting effort of the CWR Project.
2. Results
2.1. Summary of Seed Collection
During 2013–2018, partner organizations collected 4587 unique seed samples from
the 25 target genepools across the 25 partner countries (Figure 1, Supplementary Data S1,
Supplementary Tables S1 and S2). Samples were collected across seven of Vavilov’s origi-
nally identified centers of crop origin [46] (Figure 2). The samples were from 27 genera, at
least 321 species and at least 355 taxa. Ninety-nine samples are yet to be identified to the
species level. At the time of duplication, 85 species were new to the Millennium Seed Bank
(MSB). A total of 13 taxa had no previous seed collections in the MLS. Overall, 38 samples
were collected for species with the International Union for Conservation of Nature (IUCN)
conservation status of Critically Endangered (one species), Endangered (one species),
Vulnerable (two species) and Near Threatened (six species; Supplementary Data S2).
Figure 1. Distribution of unique seed samples collected in the Adapting Agriculture to Climate
Change Project (CWR Project). Green dots represent collections made during 2013–2018 in partner
countries. The country maps are not to scale.
The number of samples and taxa per genepool are listed in Figure 3. Potato was the
most highly collected genepool, with 474 samples, closely followed by eggplant, with
438 samples, both from the genus Solanum (Figure 3a). Potato also had the largest number
of taxa collected (54 taxa), far more than any other genepool targeted in the project. The
least collected genepool was chickpea, with 16 taxa. Rice had the highest number of
samples (147) in the primary genepool. All of the Bambara groundnut and carrot samples
were in the primary genepool taxa (Figure 3b).
Plants 2022, 11, 1840 6 of 18
Figure 2. Countries and number of samples collected by the Adapting Agriculture to Climate Change
Project (CWR Project) in seven of Vavilov’s centers of origin [46]. Map created using MapChart.net.
Figure 3. Samples collected per crop genepool categorized by their relationship to the crop. Samples
are defined as primary (blue), secondary (dark orange) or tertiary (gray) genepool taxa, or other taxa
within the same genus as the crop but whose relationship to the crop is unknown (light orange).
(a) Number of samples in each category. (b) Percentage of samples in each category.
Vetch wild relatives were collected from the largest number of countries (13), while
Bambara groundnut wild relatives were only collected in only one country, Nigeria
(Supplementary Table S1). Partners in Pakistan collected CWR from 17 genepools, while
those in El Salvador and Peru concentrated exclusively on bean and potato, respectively.
The number of samples per taxon varied widely. There were fewer than 10 taxon
replicates (the same taxa collected in different locations) for 185 taxa. Only 76 taxa were
collected more than 20 times. Sorghum bicolor subsp. verticilliflorum (Steud.) de Wet ex
Wiersema & J. Dahlb. was collected 107 times across four countries, with 77 of those
samples collected in Sudan.
Plants 2022, 11, 1840 7 of 18
2.2. Collection Metric
We calculated a collection metric for each genepool on the basis of the percentage of
samples collected from the initial target list and the percentage of species collected from
the initial target lists. The collection metric showed Bambara groundnut to be the genepool
for which collection targets (number of collections and taxa) were best achieved, closely
followed by alfalfa, grass pea and wheat (Figure 4, Table 1 and Supplementary Table S3).
Collecting samples in the genepools of bean, chickpea, cowpea, pigeon pea and potato
proved most difficult. For example, 60% of the target chickpea species were collected, but
only 30% of the planned samples. However, more than 60% of the target species were
collected for all the genepools.
Figure 4. Success of collecting target species and sample numbers per genepool. The collection metric
was calculated from these scores.
Table 1. Genepools categorized by collection metric score.
Collection Metric Genepool
10 All initial species and sample numbers
collected
9 Bambara groundnut
8 alfalfa, grass pea, wheat
7 barley
6 carrot, eggplant, faba bean, lentil, rice rye,sweetpotato
5 Half of initial species and sample numbers
collected finger millet, pea, sorghum, vetch
4 apple, oat
3 banana/plantain, pearl millet
2 bean, cowpea, pigeon pea, potato
1 chickpea
0 No initial species or samples collected
2.3. Multiplication, Safety Backup and Use
To date, 233 species and 4019 samples of the materials collected by the CWR Project
have been further shared from The Royal Botanic Gardens, Kew (hereinafter, Kew) to
national and international genebanks for multiplication, safety backup, and use (Table 2).
Plants 2022, 11, 1840 8 of 18
Table 2. Shipments of Adapting Agriculture to Climate Change Project (CWR Project) samples from
The Royal Botanic Gardens, Kew (Kew) to national and international genebanks for multiplication,
use and safety backup. * Material only identified to the genus level has also been shipped.
Crop Institute Total UniqueAccessions Total Species
Shipped
Alfalfa South Australian Research and DevelopmentInstitute (SARDI), Australia 348 24
Apple United States Department of Agriculture(USDA), USA 43 5
Bambara groundnut International Institute of Tropical Agriculture(IITA), Nigeria 16 1
Banana International Musa Germplasm Transit Centre(ITC), Belgium 114 7
Barley International Center for Agricultural Research inthe Dry Areas (ICARDA), Lebanon 378 17
Carrot USDA, USA 83 2
Chickpea ICARDA, Lebanon 8 3
Cowpea IITA, Nigeria 60 6
Eggplant World Vegetable Center (WVC), Taiwan 216 19
Faba bean ICARDA, Lebanon 75 5
Finger millet International Crops Research Institute for theSemi-Arid Tropics (ICRISAT), India/Niger 48 9
Grass pea ICARDA, Lebanon 270 26
Lentil ICARDA, Lebanon 64 5
Oat ICARDA, Lebanon 1 1
Oat Plant Gene Resources of Canada (PGRC),Canada 241 6 *
Pea USDA, USA 40 2
Pearl millet ICRISAT, India/Niger 170 22 *
Pigeon pea ICRISAT, India/Niger 25 3
Rice International Rice Research Institute (IRRI),Philippines 146 9 *
Rye Leibniz Institute of Plant Genetics and CropPlant Research (IPK), Germany 72 6
Sorghum ICRISAT, India/Niger 195 7 *
Vetch ICARDA, Lebanon 285 19
Wheat ICARDA, Lebanon 388 27
Total 3279 223
Pending
Bean International Center for Tropical Agricultural(CIAT), Colombia 39 9
Eggplant WVC, Taiwan 126 15
Rice IRRI, Philippines 96 8
Sweetpotato International Potato Center (CIP), Peru 21 3
Total 282 35
Plants 2022, 11, 1840 9 of 18
Through this process, material will in due course be backed up in the Svalbard Global
Seed Vault (SGSV). In total, 508 unique samples were deposited by the International Center
for Agricultural Research in the Dry Areas (ICARDA) in the SGSV between 2019 and 2021,
and 51 potato accessions by the International Potato Center (CIP) in 2021. The University
of Costa Rica also deposited 51 rice samples in the SGSV in February 2020.
There have been two very substantial multiplication efforts within the CWR Project.
ICARDA initially focused on 748 CWR samples in the genepools of barley, faba bean,
grass pea, lentil, wheat, and vetch. A total of 624 samples now have sufficient seeds
after three multiplication rounds and are available for distribution. CIP is increasing the
availability of 270 wild potato samples by multiplication and characterization. To date, all
three goals of having sufficient seeds, being virus free and being taxonomically verified
have been achieved for 149 accessions. Additional, smaller-scale multiplications have
been undertaken at the Agricultural Research Institute of the Ministry of Agriculture in
Cyprus, the Ethiopian Biodiversity Institute, the Instituto Nacional de Investigaciones
Agropecuarias in Ecuador, the Lebanese Agricultural Research Institute (in collaboration
with ICARDA), the Malaysian Agricultural Research and Development Institute, the Plant
Genetic Resources Centre in Uganda and the University of Costa Rica.
While it is too early for all of the collected material to have been evaluated or used
in breeding, some newly collected CWR are already being incorporated into pre-breeding
programs. For example, all alfalfa CWR samples have been regenerated, characterized,
and preliminarily evaluated at the South Australian Research and Development Institute
(SARDI) for a range of traits including forage production, habit, flower color, pod coiling
and fall dormancy. Some alfalfa materials are now part of a wider evaluation trial currently
underway in Australia, Chile, Kazakhstan, and China (Inner Mongolia) [26], and will soon
be trialed in Kyrgyzstan, Pakistan, and Tunisia. Three pre-bred lines generated using
material collected under the CWR Project were included in these evaluation trials. Two of
these lines showed moderate–high cold tolerance.
3. Discussion
The CWR Project has demonstrated that it is possible to have a successful international
collaboration to collect and conserve germplasm across 25 countries in centers of diversity
and other regions on five continents. The cooperation of a wide range of partners has
improved the diversity, quantity, and accessibility of collections of CWR of 28 crops of
global significance (Figure 5). A total of 4587 samples were collected spanning at least
365 CWR taxa (Figure 3). Though the global results are impressive, the impact at the
national scale has arguably been even greater. For example, the CWR holdings in Embrapa,
Brazil [50], and the Lebanese Agricultural Research Institute were doubled during the
project period. In Nepal, the project expeditions resulted in the first CWR collections to be
conserved in that country [51].
Unsurprisingly, some genepools proved easier to collect than others. In most cases,
finding the target number of samples was more difficult than meeting the target number of
species. When analyzed at the genepool level, three legumes (bean, chickpea, and pigeon
pea) had particularly low collection metric scores, yet at least 60% of their species targets
were met. This pattern was not reflected in all countries, and the collection metric did not
assess additional collections. In many cases, species and samples beyond the target list
were collected. For example, the Costa Rican CWR Project partners targeted 49 samples
in the bean genepool, but successfully collected 70 samples. Despite having the most
collections, potato scored weakly in the collection metric, because there were few replicates
of the target species. Despite this, other important collections were made, for example,
the collection of Solanum ayacuchense Ochoa and Solanum olmosense Ochoa from Ecuador
and Peru, which were previously entirely missing from ex situ collections. Although wild
bananas proved difficult to collect, the project has stimulated the launching of additional
collecting programs to improve the conservation and availability of banana CWR [52], so
the outlook is hopeful even for this genepool.
Plants 2022, 11, 1840 10 of 18
Figure 5. Collectors share their comments on collections of alfalfa, potato and rice. (a) Quote refers to
Medicago marina collected in Georgia. The Georgian Adapting Agriculture to Climate Change Project
(CWR Project) partners collected seeds from five populations of M. marina. Photo—Medicago marina.
Ruth Eastwood. (b) Quote refers to Solanum ayacuchaense and Solanum ortegae, which were discovered
in the wild for the first time in Peru as part of the CWR Project. Photo—Herbarium specimen of
Solanum ayacuchaense. International Potato Center (CIP), Peru. (c) Quote refers to Oryza coarctata,
which was collected twice in Pakistan by CWR Project partners. Photo: Wild rice Oryza coarctata
found in Pakistan. Bio-resources Conservation Institute/Shakeel Jatoi.
Some new records and populations were found by the project partners. The gap
analysis did not attempt to predict where new species could be found, and gave only
poor indications of where new populations of rare and endemic species might be, due to
insufficient data. In Costa Rica, the existence of Phaseolus microcarpus Mart. was confirmed
and partners went on to identify 13 populations, eight of which have been conserved in ex
situ seed collections for the first time [53]. A new species, Phaseolus angucianae Debouck &
Araya, was also discovered in Costa Rica [54]. In Pakistan, Cicer macracanthum Popov was
found at an altitude 500 m higher than previously recorded. The first collections of Vicia
pyrenaica L. were conserved in Spain under the CWR Project. New discoveries included the
first records of potato spindle tuber viroid in wild Solanum species, adding to knowledge
about this disease [55].
The chief strength of the CWR Project has been collaboration at all levels. An invet-
erate networker, Vavilov would have appreciated this. At least 157 people from different
scientific fields, countries, and organizations participated in the collecting effort alone
(Supplementary Data S3). The expanded network of people interested in CWR means that
it is more likely the collected samples will be used in research and in the development
of climate-ready crops. Already, additional data, such as germination protocols for new
species [56] and characterization data [57], have been generated for some samples. This
could accelerate the discovery of new adaptive traits and stimulate research [58,59].
Plants 2022, 11, 1840 11 of 18
Technical support, training provided to collectors and the distribution of collecting
guides prepared by the project have contributed to the success of the collecting effort.
Substantial resources were invested in these activities, and the investment has clearly paid
off. An independent review of the project commented that “the skills and experience
acquired by the national partners has enhanced their technical and project management
capacity and positions them for participation in future global initiatives” [60]. For some
countries in which existing data were minimal and ecogeographic diversity considerable,
the maps of predicted species distributions in the guides were less reliable, but will improve
in the future as more data are available and analytical tools evolve. Adequate investment
in such supporting elements is strongly recommended for future projects.
Many challenges were encountered from planning to implementation of the project.
For example, international access and benefit-sharing laws and phytosanitary regulations,
and their national implementation, were often difficult to navigate. Some countries were
unable or unwilling to participate due to impediments in implementing the Plant Treaty.
Encouragingly, some countries that are not Parties nevertheless agreed to work under the
framework of the Plant Treaty for this project. In Georgia, it served as a learning experience
prior to the ratification of its membership. Obtaining permits for collection and export
took far longer than expected. In some cases, authorizations had to be obtained at a local
level and implemented in each planned collecting area. The treatment of CWR varied in
different countries. In some cases, they fell under environmental regulations, in other cases
the agricultural ministry, and in some cases both.
Alarmingly, collecting reports detailed many instances of habitat destruction and
damaging land-use changes. Despite collectors’ best efforts, some under-collected species
could still not be found and known populations of species were found to have been
destroyed. The last known population of Aegilops crassa Boiss in Armenia was not found
due to construction in its habitat. In Malaysia, collectors reported that Solanum cumingii
Dunal had disappeared from its previously known locations, which are now farmland.
In 2018, a collector returned to the locality of San Pedro de Pilas, Lima Province, central
Peru, where he had collected Solanum cantense Ochoa in semi-arid scrubland more than 20
years previously. Lamentably, the scrubland had been replaced by a football field and a
water reservoir.
Ironically, collecting CWR, one of the solutions for adapting to, and mitigating the
effects of, climate change, is getting harder due to climate change. The Intergovernmental
Panel on Climate Change [61] reports that widespread and severe losses and damage
to human and natural systems are being driven by human-induced climate change that
increase the frequency, intensity, or duration of extreme weather events. Extreme weather
conditions indeed complicated collecting efforts, by altering the phenology of flowering
and fruiting, limiting seed set and preventing physical access to some populations. In
2014, the Cypriot team started collecting while the country was under one of the worst
droughts in its history. In 2016, in West Kordofan state, Sudan, rains were poor, and plants
struggled to set seed. Unseasonable weather across Vietnam in 2016 resulted in premature
seed maturation. The El Niño rains and flooding in 2017 left roads in Peru impassable and
collections had to be postponed until the following year. In Spain, where the spring of 2016
was extremely dry, collections were difficult and sometimes, impossible. Then in 2017, in
Andalusia, the vegetative cycle of the plants was altered by unseasonable weather and
fruits of Lathyrus amphicarpos L. were produced earlier than usual.
A major legacy of the CWR Project will be increased national capacity, knowledge, and
passion for CWR collection. The sustainability of the initiative depends on the integration of
CWR conservation and use into national priorities, and the availability of national funding
for further collecting and maintaining collections. There is evidence of this happening. In
Pakistan and El Salvador, CWR collecting work has continued beyond the CWR Project.
In Nepal, the collection of CWR has become an additional government-funded activity
for the genebank. The University of Costa Rica has funded additional rescue collecting.
New initiatives include a collaboration between The Plant Genetic Resources Programme
Plants 2022, 11, 1840 12 of 18
in Pakistan and the National Herbarium to include CWR species, and the development
of a banana field genebank by the National Agricultural Research Centre in Nepal. The
pre-breeding project [62] funded by the Templeton World Charity Foundation, Inc. and
the Biodiversity for Opportunities, Livelihoods and Development (BOLD) Project [63]
funded by the Norwegian government build on the CWR Project and plan to extend CWR
pre-breeding and evaluation.
Ongoing climate change, the continuing global pandemic, and an uncertain policy
environment mean that this may be the last big global germplasm collecting effort. The
project has continued the work started in the 1910s by Vavilov and since taken up by many
others, but it is not complete. Gaps in collections remain, genetic erosion continues, and the
need for diversity is more urgent than ever. The CWR Project has shown that coordinated
action can effectively address CWR conservation across genepools. The need for genetic
material for crop improvement is only going to increase given all the challenges faced by
humankind. Many more crop genepools within and outside Annex 1 need the focus that
was provided by this project. Large-scale, coordinated CWR conservation makes an impact,
and must continue.
4. Materials and Methods
4.1. Collecting Approach
The collecting effort encompassed the wild relatives of 28 crops in Annex I of the
Plant Treaty, which belong to 25 genepools: alfalfa (lucerne), apple, African rice, Asian rice,
Bambara groundnut, banana, barley, bean, bread wheat, carrot, chickpea, cowpea, durum
wheat, eggplant (aubergine), faba bean, finger millet, grass pea, lentil, oat, pea, pearl millet,
pigeon pea, plantain, potato, rye, sorghum, sweetpotato, and vetch. Three pairs of crops
share genepools: African and Asian rice, banana and plantain, and bread and durum wheat,
and are referred to in this paper as rice, banana, and wheat. Species nomenclature followed
The Harlan and de Wet CWR inventory [42]. With limited resources, the CWR Project had
to translate the conservation priorities from the global gap analysis into a global collecting
strategy which was as cost-effectively and pragmatically as possible. This meant balancing
genepools and geography to capture maximum diversity both within and among taxa.
Supplementary Data S4 details the CWR Project target list.
4.2. Partnership Approach
Coordinators from the MSB at Kew and the Crop Trust approached 34 national partners
in countries harboring the greatest numbers of CWR of priority genepools [41–43].
Initial lists of taxa were provided at the first approach. Where possible, the CWR
Project attempted to initiate or strengthen collaborations between agricultural and con-
servation organizations within countries, as interest in CWR spans both disciplines. The
project required compliance with all applicable national and international legislation and
policies. Plant Treaty focal points and the Secretariat of the Plant Treaty provided sup-
port. Where fruitful, discussions moved to project development, including confirming the
taxa list, and finally to implementation of a grant agreement between the Crop Trust and
national partner(s). Partners in the following countries finally participated in the project:
Armenia, Azerbaijan, Brazil, Chile, Costa Rica, Cyprus, Ecuador, El Salvador, Ethiopia,
Georgia, Ghana, Guatemala, Italy, Kenya, Lebanon, Malaysia, Nepal, Nigeria, Pakistan,
Peru, Portugal, Spain, Sudan, Uganda, and Vietnam. Thus, CWR Project partners collected
materials in at least seven of Vavilov’s eight ‘main centers of origin of cultivated plants’,
and at least 14 of the 25 CWR partner countries were visited by Vavilov. Supplementary
Table S1 shows the genepools targeted in each of the 25 partner countries.
4.3. Planning
Country-specific CWR collecting guides were compiled to complement the knowledge
of local experts. These aided the planning of collecting missions by including locality
data from the CWR occurrence database, as well as a map of the known distribution
Plants 2022, 11, 1840 13 of 18
from herbarium data and existing seed collections and another map of the modeled range
indicating gaps for collection (Figure 6) [43]. Where possible, an indication of flowering
and fruiting time was included. To facilitate identification, descriptions and images were
provided. An image of mature seeds and a recommended collection method were provided
to maximize the quality of seeds collected. Partners planned their collecting missions using
these guides in combination with guidelines from Kew, including technical information
sheets [64], and their own expertise and experience. Some partners developed species
identification sheets in their own language or carried out additional analyses. In some
cases, multiple national teams conducted collecting missions in the field simultaneously
at the optimal time for seed collection across wide distances. Collecting teams included
taxonomists to support identification in the field. Collecting organizations had to obtain
collecting permits and all other documents required by local authorities prior to initiating
field work.
Figure 6. Example of distribution and target maps provided in the Crop Wild Relative (CWR)
Collecting Guides. (a) Predicted distribution of Malus orientalis in Georgia based on herbarium and
existing germplasm records. The bright green shaded area, showing the predicted distribution,
was modeled using known localities, which are also plotted on the map. (b) Target collecting areas
(potential gaps) in ex situ collections of Malus orientalis. The pink shaded areas highlight areas in
the predicted distribution from which no germplasm had yet been collected, indicating where seed
collections would be targeted by the CWR Project.
Special kits were assembled by Kew for seed collecting, cleaning, and drying, and the
kits were then provided to the partners (Supplementary Data S5). These were designed
to support best practices in seed handling, to maximize the quality and longevity of the
collected materials. Alongside equipment, a training program was organized for national
partners through regional training courses in Australia, Azerbaijan, Chile, Georgia, Ghana,
Malaysia, Spain, Uganda, and Vietnam, as well as training at the MSB and several national
facilities. A total of 174 participants, representing all partner countries, received tailored
seed collecting and conservation training.
4.4. Collecting
National collecting programs were designed to span multiple years due to the geo-
graphic coverage required, the need to find new populations and to allow for variation in
weather conditions.
At each collection site, partners assessed the size of the CWR population and the
level of seed maturity before randomly sampling approximately 20% of mature seeds
available. Seeds were collected from at least 50 plants to represent the genetic diversity of
Plants 2022, 11, 1840 14 of 18
the populations adequately [64]. Where this was not feasible, as many plants were sampled
as possible.
The aim was that each unique sample (seeds from one taxon at one sample site) should
have three elements: (1) The sample should comprise more than 10,000 seeds. For some taxa,
it was necessary to sample other plant parts (e.g., tubers); (2) Dried plant specimen(s) to
allow for later verification of the identification and for deposit in both a national herbarium
and the Kew herbarium; and (3) Passport data following specific CWR Project requirements
(Supplementary Method S1), which included taxon, locality, and date.
4.5. Post-Collection Handling
Post collection, seed samples were cleaned to remove empty or infested seeds and
non-seed plant material, and dried. At this stage, partners flagged small or low-quality
collections. In addition, samples were accessioned into the collection database and given a
unique identifier. A portion of the sample, generally one-third, was placed into long-term
conservation in national facilities. Most partners shipped the rest of the sample to Kew
under the standard material transfer agreement of the Plant Treaty for duplicate storage
and verification of identification. In cases where shipment to Kew was not possible, i.e.,
due to a very small collection size or legal requirements, other facilities were sought to
ensure safety duplication. Samples collected as tubers were duplicated at other facilities
and, where possible, grown into plants from which seeds were later collected (in line with
genebank workflows, other conservation methods will be applied in the future if seeds
cannot be produced). Samples at Kew were further cleaned and dried, if required, and
placed in long-term storage at −20 ◦C. To check viability and facilitate use, germination
tests were carried out for each seed sample.
With the agreement of collecting partners, the CWR of each genepool were sent from
Kew to national and international genebanks, where the samples can be multiplied to
increase seed availability, used for research and pre-breeding, and backed up in the SGSV.
When samples comprised fewer than 10,000 seeds, project partners first tried to re-
collect materials from the same population the following year. Where small sample sizes
persisted, multiplication was considered to ensure sufficient material for access. To this
end, the CWR Project undertook specific multiplication projects with the CIP and ICARDA.
Some collecting partners also carried out multiplication, particularly when specific growth
conditions were required.
4.6. Data
Passport data for collected samples were gathered by the national partners, included
in their databases, and shared with Kew for inclusion in the Seed Bank Database as samples
were accessioned in the MSB. These data were then shared with Genesys [65]. A CWR
Project page in Genesys details all the samples collected under the project that are now
conserved ex situ [51].
4.7. Collection Metric
The collection metric was calculated to assess whether the samples and taxa within
a genepool were collected according to the initial target lists agreed with partners. The
metric was the sum of two criteria; the percentage of samples collected from the initial
target list, and the percentage of species collected from the initial target lists. Both criteria
were scored 0–5 as follows: 1–50% = 0, 51–60% = 1, 61–70% = 2, 71–80% = 3, 81–90% = 4
and 91–100% = 5. The scale of the collection metric ranged from 0 (no samples from the
initial list were collected) to 10 (all species and samples from the initial lists were collected).
This allowed us to rank the genepools in terms of the success of collection.
Supplementary Materials: The following supporting information can be downloaded at: https:
//www.mdpi.com/article/10.3390/plants11141840/s1. Supplementary Data S1: CWR Project col-
lected samples dataset used for analysis; Supplementary Data S2: IUCN conservation status for CWR
Plants 2022, 11, 1840 15 of 18
collected at species level. Data from https://www.iucnredlist.org/ (accessed on 25 August 2021);
Supplementary Data S3: List of collectors; Supplementary Data S4: CWR Project target; Supplemen-
tary Data S5: Collection kit contents; Supplementary Table S1: Distribution of genepool targets across
countries; Supplementary Table S2: Genepool summaries of seed samples collected in the CWR
Project; Supplementary Table S3: Collection metric scoring; Supplementary Method S1: CWR Project
Passport Data Form.
Author Contributions: Conceptualization, N.P.C.-Á., H.D. (Hannes Dempewolf), L.G., J.V.M. and
P.P.S.; Data curation, R.H. (Ruth Harker), U.L. and M.O.; Formal analysis, R.J.E.; Funding acquisition,
H.D. (Hannes Dempewolf) and L.G.; Investigation, R.J.E., B.B.T., L.M.A., Z.I.A., S.E.A., R.A. (Richard
Allen), A.A. (Ahmed Amri), N.L.A., R.A. (Rodolfo Araya), A.A. (Aydin Asgerov), K.A., T.A., A.M.B.,
S.K.B., J.M.B., J.B., E.B., A.B.A., M.L.B., N.P.C.-Á., P.C., N.F.C., A.S.C., C.P.C., A.D., L.D.l.R., D.G.D.,
H.D. (Hannes Dempewolf), H.D. (Hiba Dokmak), D.E., G.A.-E., A.F., C.F., S.G., R.M.G., K.H.G., L.G.,
R.H. (Ruth Harker), R.H. (Roberta Hope), A.W.H., S.A.J., M.K., D.K., A.C.K., P.L.-L., R.P.M., A.T.M.,
N.C.M.-C., D.M., M.S.M.A., M.B.M., M.A.M.G., T.M.-P., E.T.I.M., Á.M.-A., A.M., J.V.M., J.W.M., A.N.,
H.N., D.O.N., M.O., A.U.O., S.O., F.O.-K., A.P., T.R.P., M.A.A.P.d.C., J.P., G.R., A.S., D.S.S., S.U.S., P.P.S.,
D.A.S., M.T., C.T., Á.T., J.T., D.T.V., T.D.V., M.J.W., M.Y., C.Z. and B.K.; Methodology, R.J.E., B.B.T.,
N.P.C.-Á., H.D. (Hannes Dempewolf), L.G. and J.V.M.; Project administration, R.J.E., B.B.T., C.P.C.,
H.D. (Hannes Dempewolf), L.G., J.V.M., J.T. and B.K.; Writing—original draft, R.J.E., B.B.T., L.G., N.J.
and B.K.; Writing—review and editing, L.M.A., Z.I.A., S.E.A., Richard Allen, A.A. (Ahmed Amri),
N.L.A., R.A. (Rodolfo Araya), T.A., A.M.B., S.K.B., J.M.B., J.B., E.B., A.B.A., M.L.B., N.P.C.-Á., N.F.C.,
A.S.C., C.P.C., A.D., L.D.l.R., D.G.D., H.D. (Hannes Dempewolf), G.A.-E., A.F., C.F., R.M.G., K.H.G.,
R.H. (Ruth Harker), A.W.H., S.A.J., M.K., D.K., A.C.K., P.L.-L., U.L., R.P.M., A.T.M., N.C.M.-C., D.M.,
M.S.M.A., M.B.M., M.A.M.G., T.M.-P., E.T.I.M., Á.M.-A., A.M., J.V.M., J.W.M., A.N., H.N., D.O.N.,
M.O., S.O., F.O.-K., A.P., T.R.P., M.A.A.P.d.C., J.P., G.R., A.S., D.S.S., S.U.S., P.P.S., D.A.S., M.T., C.T.,
Á.T., J.T., D.T.V., T.D.V., M.J.W., M.Y. and C.Z. All authors have read and agreed to the published
version of the manuscript.
Funding: This work was undertaken as part of the initiative “Adapting Agriculture to Climate
Change: Collecting, Protecting and Preparing Crop Wild Relatives”, which is supported by the
Government of Norway. Grant number from the Norwegian Government: *QZA-14/0005* for
funding the initiative “Adapting Agriculture to Climate Change: Collecting, Protecting and Preparing
Crop Wild Relatives”. The project was managed by the Global Crop Diversity Trust with the
Millennium Seed Bank of the Royal Botanic Gardens, Kew, UK and implemented in partnership
with national and international genebanks and plant breeding institutes around the world. For
further information, please go to the project website: http://www.cwrdiversity.org/ (accessed on
1 June 2022).
Data Availability Statement: Data are available at Genesys (https://www.genesys-pgr.org/subsets/
1812d281-0cad-4293-ad71-4d2ef8caabd1 (accessed on 1 April 2021)) for 4264 of the 4587 accessions
collected. Of these 4264 accessions, 3544 were accessioned at the MSB, Kew. The remaining 720 acces-
sions could not be transferred to the MSB because of low seed numbers or national restrictions, or
because they were sent to CGIAR centers. Data for 323 samples are not available on Genesys because
these samples have not yet been accessioned.
Acknowledgments: We thank all institutes and individuals for the tremendous effort they devoted
to this project. We thank Advisory Board members of the CWR Project Alvaro Toledo (representative
of the Secretariat of the International Treaty on Plant Genetic Resources for Food and Agriculture,
FAO), Åsmund Bjørnstad (Norwegian University of Life Sciences), Cary Fowler (Former Executive
Director, Global Crop Diversity Trust), Colin Clubbe (Royal Botanic Gardens, Kew), Geoff Hawtin
(Advisor to the Global Crop Diversity Trust), Mahmoud Solh (Former Director General, ICARDA),
Marie Haga (Former Executive Director, Global Crop Diversity Trust), Peter Crane (President of
Oak Spring Garden Foundation), and Susan McCouch (Cornell University, USA); and Paul Smith
(Secretary General of Botanic Gardens Conservation International) for their expertise and guidance.
We thank Nigel Maxted (University of Birmingham) and his group who were instrumental in the
initial stages of the CWR Project.
Conflicts of Interest: The authors declare no conflict of interest. The funders had no role in the design
of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or
in the decision to publish the results.
Plants 2022, 11, 1840 16 of 18
Abbreviations
BOLD—Biodiversity for Opportunities, Livelihoods and Development; CIAT—International
Center for Tropical Agricultural; CIP—International Potato Center; CWR—Crop wild relatives; CWR
Project—Adapting Agriculture to Climate Change Project; IITA—International Institute of Tropical
Agriculture; ICARDA—International Center for Agricultural Research in the Dry Areas; ICRISAT—
International Crops Research Institute for the Semi-Arid Tropics; IPK—Leibniz Institute of Plant
Genetics and Crop Plant Research; IRRI—International Rice Research Institute; ITC—International
Musa Germplasm Transit Centre; IUCN—International Union for Conservation of Nature; Kew—The
Royal Botanic Gardens, Kew; MLS—multilateral system, MSB—Millennium Seed Bank; PGRC—Plant
Gene Resources of Canada; Plant Treaty—International Treaty on Plant Genetic Resources for Food
and Agriculture; SARDI—South Australian Research and Development Institute; SGSV—Svalbard
Global Seed Vault; USDA—United States Department of Agriculture; WVC—World Vegetable Center.
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