The Ex Situ Conservation of Plant Genetic Resources

The Ex Situ Conservation of Plant Genetic Resources

by

J.G. Hawkes, N. Maxted and B.V. Ford-Lloyd

The University 0/ Birmingham, u.K.

SPRINGER SCIENCE+BUSINESS MEDIA, B.V.

A C.I.P. Catalogue record for this book is available from the Library of Congress.

ISBN 978-94-010-5805-6 ISBN 978-94-011-4136-9 (eBook) DOI 10.1007/978-94-011-4136-9

Printed on acid-free paper

All Rights Reserved © 2000 Springer Science+Business Media Dordrecht

Originally published by Kluwer Academic Publishers in 2000 Softcover reprint ofthe hardcover I st edition 2000

No part of the material protected by this copyright notice may be reproduced or utilized in any form or by any means, electronic or mechanical,

including photocopying, recording or by any information storage and retrieval system, without written permission from the copyright owner.

We dedicate this book to

the late

Sir Otto Frankel

of Canberra, Australia

who did more than anyone else, apart from N.I. Vavilov, to develop the Science of Genetic Resources

and who died on 21st November 1998 in his 98th year.

Contents Preface xi

Acronyms and Abbreviations xiii

Figures, Plates, Tables and Appendices xv

Color Plates xix

1 The Genetic Resources of Plants and Their Value 1 1.1 The Biodiversity Challenge 1 1.2 The Definition of Biodiversity 2 1.3 Plant Genetic Resources 3 1.4 The Need to Conserve Botanical Diversity 4 1.5 The Causes of Plant Genetic Diversity Loss 6 1.6 The Conservation / Development Paradox 7 1.7 The Exploitation of Plant Diversity in Crops 8 1.8 The Practice of Conservation 9 1.9 The Advantages and Disadvantages of Different Ex Situ Techniques 13 1.10 Complementary Conservation Strategies 16

2 Evolution of Plants Under Domestication 19 2.1 Plants: Cultivated and Wild 19 2.2 Genetic Changes During Domestication 19 2.3 Alphonse de Candolle's Views on Cultivated Plant Origins 20 2.4 Darwin's Views on Plant Domestication 20 2.5 The Ecological Background of Plant Domestication 21 2.6 N.!. Vavilov's Centres of Crop Origins and Diversity 28

3 The Plant Genetic Resources Conservation Movement 32 3.1 Ethical and Conservation 32 3.2 A Brief History of Plant Genetic Conservation and Use 33 3.3 Critical Issues for Contemporary Plant Genetic Resources 39

4 Preparing To Collect For Ex Situ Conservation 43 4.1 Conservation Project Commission 43 4.2 Selection of Target Areas 44 4.3 Selection of Target Species 44 4.4 Ecogeographic Surveys 53 4.5 Selection of the Collection Team 59 4.6 Expedition Timing 60 4.7 Local Administrative Requirements 60 4.8 Collecting Equipment 61 4.9 Survey Missions 61

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5 Exploration and Field Collection 63 5.1 Sampling Techniques 63 5.2 Types of Collecting Site 64 5.3 Field Sampling 65 504 Specialised Type of Plant Collecting 71 5.5 Conservation Products 75 5.6 Duplication of Collected Materials 81

6 Seed Gene Bank Conservation 82 6.1 Conventional Ex Situ Techniques 82 6.2 Base and Active Gene Banks 82 6.3 Seed Storage 83 604 Intermediate and Recalcitrant Seeded Species 91 6.5 Users of Seed Stored in Gene Banks 91

7 Field Gene Banks, Botanic Gardens In Vitro, DNA and Pollen Conservation 92 7.1 Field Gene Banks and Orchards 92 7.2 Botanic Gardens 94 7.3 In Vitro Techniques 100 7 A DNA Storage 105 7.5 Pollen Storage 106

8 World Ex Situ Collections of Germplasm 108 8.1 World Collections of Major Crops 108 8.2 Numbers of Accessions in Storage 109 8.3 Security of Collections 114 804 The Cost of Conservation 114 8.5 How Unique Are Accessions Within Gene Banks? 115 8.6 Field Gene Banks, In Vitro Storage and Botanic Gardens Collections 115 8.7 How Much is Enough? 115 8.8 Core Collections 117

9 Community-Based Conservation 120 9.1 Local Communities And Conservation 120 9.2 Communities Working To Conserve Plants 121 9.3 Communities Working With Professional Conservationists 127 904 Communities and Professional Conservationists Working Together 132

10 Plant Genetic Resource Utilization 10.1 Germplasm Exploitation 10.2 Phenotypic Characterisation and Evaluation 10.3 Genetic Evaluation and Analysis lOA Use of Molecular Markers in Germplasm Evaluation 10.5 Evaluating the Value of Conserved Plant Diversity 10.6 Direct Utilisation of Genetic Resources

135 135 136 137 138 142 143

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11 Genetic Conservation Information Management 146 11.1 The Need For Information Management 146 11.2 Data Capture and Manipulation 147 11.3 Accessing Existing Conservation Information 156 11.4 The Efficient Management of Conservation Data 158 11.5 Central Crop Databases 159 11.6 Data Ownership 163

12 Conservation Case Studies 164 12.1 Case Studies of Plant Genetic Resource Conservation 164 12.2 Rice 164 12.3 Wheat 167 12.4 Potatoes 171 12.5 Bananas and Plantains 174 12.6 Coffee 176 12.7 Clover 179 12.8 Leucaena 183 12.9 Asiatic Slipper Orchids 186

13 The Future of Ex Situ Conservation 190 13.1 Towards the Future 190 13.2 The Human Population and its Impact 190 13.3 Specific Ex Situ Conservation Activities 194 13.4 Human Needs Linked to Biodiversity Conservation 199 13.5 Conservation Actions for the New Millennium 201

References 205

Appendices 231

Index 241

Preface

It is a distressing truism that the human race during the last millennium has caused the exponential loss of plant genetic diversity throughout the world. This has had direct and negative economic, political and social consequences for the human race, which at the same time has failed to exploit fully the positive benefits that might result from conserving and exploiting the world's plant genetic resources.

However, a strong movement to halt this loss of plant diversity and enhance its utilisation for the benefit of all humanity has been underway since the 1960's (Frankel and Bennett, 1970; Frankel and Hawkes, 1975). This initiative was taken up by the Convention on Biological Diversity (CBD, 1992) that not only expounds the need to conserve biological diversity but links conservation to exploitation and development for the benefit of all. Article 8 of the Convention clearly states the need to develop more effective and efficient guidelines to conserve biological diversity, while Article 9, along with the FAO International Undertaking on Plant Genetic Resources, promotes the adoption of a complementary approach to conservation that incorporates both ex situ and in situ techniques.

Although both ex situ and in situ techniques have their advantages and disadvantages, they should not be seen or practised as alternatives. It is now accepted that the most appropriate model to adopt is a holistic, complementary approach. Frequently one technique will act as a backup to another. Each has an important role to play, and one or other may receive more emphasis according to the crop or wild species concerned, and the composition and state of the biological community, silvi- or agro-ecosystem where the target species is found.

The Convention on Biological Diversity overall, however, gives particular prominence to in situ techniques. Most conservationists would accept that in situ conservation is the ideal mode, but while ecosystems, species and genetic diversity continue to be so severely threatened and those exploiting diversity require easy access, in reality ex situ and in situ techniques should share prominence and neither should predominate. Our last book, "Plant Genetic Conservation - the In situ Approach" (Maxted, Ford-Lloyd and Hawkes, 1997a) focused explicitly on in situ plant conservation techniques; thus we felt there was now a need for a sister volume that explicitly focused on the "Ex situ Conservation of Plant Genetic Resources". We felt there was a need to redress the balance and emphasize the need to apply both in situ with ex situ techniques in a truly complementary manner. As with the previous volume, we also wish to promote an informed debate of the scientific principles underlying plant genetic conservation as a whole.

We have approached the subject of ex situ conservation of plant genetic diversity from theoretical and practical viewpoints, drawing ideas together from published and unpublished sources, and from our own extensive practical field experience, conserving plant genetic. diversity around the world. The book is divided into thirteen chapters: Chapters 1 to 3 introduce the genetic conservation of plants; Chapters 4 and 5 focus on field germplasm collection; Chapters 6 to 9 discuss the ex situ conservation techniques available; Chapters 10 and 11 deal with the management and utilisation of the collections once conserved; Chapter 12 provides a series of case studies that briefly discuss the conservation of diverse plant groups; and the finally Chapter. 13 provides our view of the future of ex situ conservation of plant genetic diversity, highlighting some of the most important and sometime contentious issues.

xi

xii

We acknowledge with gratitude many colleagues who have provided help and encouragement during the preparation of this book. Specifically, we thank them for: reviewing drafts of the text, L. Daugherty, M.E. Dulloo, L. Guarino, A. Hamilton, G.C. Hillman, C.E. Hughes, M.T. Jackson, S.P. Kell, E.J. Lamont, S. Linington, G. Sieve-King and M. van Slageren; and for permitting use of their photographs, P. Cribb, M. Jackson, CIP IPGRI, the N.!. Vavilov Institute of Plant Industry and the Royal Botanic Gardens, Kew.

Finally, we had hoped to include a forward by Sir Otto Frankel - a well-known world authority on plant genetic resources. Sadly, Otto died in his 98th year after a lifetime devoted to cereal breeding and the promotion of plant genetic resources conservation and use. We therefore wish to dedicate this book to his memory.

J.G. Hawkes N. Maxted B.V. Ford-Lloyd January 2000

Acronyms and Abbreviations

AGIS BGCI CBD CABI

United States Agricultural Genome Information Server Botanic Gardens Conservation International Convention on Biological Diversity Commonwealth Agricultural Bureau International (also abbreviated as

CAB International) CGIAR Consultative Group on International Agricultural Research CIA T* Centro Internacional de Agricultura Tropical CIFOR* Centre for International Forestry Research CIMMYT* Centro Intemacional de Mejoramiento de Maiz y Trigo CIP* Centro Internacional de la Papa CITES Convention on International Trade in Endangered Species of Wild Fauna

COP CSIRO CUPGR DBMS ECP/GR ERIN

and Flora Conference of the Parties (of the CBD) Commonwealth Scientific and Industrial Research Organization, Australia

Conservation and Utilization of Plant Genetic Resources Database Management System

European Cooperative Programme for Crop Genetic Resources Networks Environmental Resources Information Network

ETI EUCARPIA EUFORGEN FAO

Expert-Centre for Taxonomic Identification European Association for Research on Plant Breeding European Forest Genetic Resources Programme Food and Agriculture Organization of the United Nations General Agreement on Tariffs and Trade GATT

GEF GIS GPA GPS GRAIN GRID GRIN

Global Environment Facility. Geographical Information Systems Global Plan of Action for Conservation and Use ofPGR (ofFAO) Geographical Positioning Systems

Genetic Resources Action International Global Resources Information Database (ofUNEP) United States Genetic Resources Information Network

IARC* International Agricultural Research Centre IBP International Biological Programme IBPGR * International Board for Plant Genetic Resources (now IPGRI) ICARDA * International Centre for Agricultural Research in the Dry Areas ICRAF* International Centre for Research in Agroforestry ICRISAT* International Crops Research Institute for the Semi-Arid Tropics ICSU International Council of Scientific Unions IITA* IK ILCA* ILRAD* ILRI* INIBAP* IPGRI* IRRI*

International Institute for Tropical Agriculture Indigenous Knowledge

International Livestock Centre for Africa (now part ofILRI) International Laboratory for Research on Animal Diseases (now part ofILRI)

International Livestock Research Institute International Network for the Improvement of Banana and Plantain International Plant Genetic Resources Institute (formerly IBPGR)

International Rice Research Institute

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ISTA IUCN HDRA NGO PGR PGRFA PGRP RAFI SINGER SGRP SBSTTA SWR

International Seed Testing Association International Union for the Conservation of Nature and Natural Resources Henry Doubleday Research Association Non-governmental Organisation Plant Genetic Resources

Plant Genetic Resources for Food and Agriculture United States National Plant Genome Research Programme Rural Advancement Foundation International

System-wide Information Network for Genetic Resources System-wide Genetic Resources Programme

Subsidiary Body on Scientific Technical and Technological Advice (ofthe CBD) State of the World's Plant Genetic Resources for Food and Agriculture

report TAC Technical Advisory Committee (of the CGIAR) UKPGRG United Kingdom Plant Genetic Resources Group UNCED United Nations Conference on the Environment and Development UNDP United Nations Development Programme UNEP United Nations Environment Programme UPOV Union for the Protection Of new Varieties of plant WARDA * West Africa Rice Development Association WCMC World Conservation Monitoring Centre WRI World Resources Institute WWF World Wide Fund for Nature WWW World Wide Web

Figures, Plates, Tables and Appendices

Figures

Figure 1.1. Diversity from the gene to the community (from Frankel et al., 1995).

Figure 1.2. The Structure of IUCN Red List Categories (lUCN, 1994).

Figure 1.3. Genetic erosion - a loss of genetic diversity (lPGRI, 1993).

Figure 1.4. A Model for Plant Genetic Conservation (Maxted et al., 1997c).

Figure 1.5. Hypothetical representation of the proportions of the gene pool conserved using seven different conservation techniques for different crops: a) equal segment of the gene pool conserved using different techniques; b) combination of conservation strategies applicable for root or tuber crop, c) combination of conservation strategies for orthodox seed producer, d) combination of conservation strategies for orthodox seed-producing forest species. Note: 1 = seed storage; 2 = field gene bank; 3 = in vitro storage; 4 = pollen storage; 5 = DNA storage; 6 = genetic reserve; and 7 = on-farm conservation (Taken from Maxted et ai, 1997c).

Figure 2.1. The Vavilov Centres of Crop Diversity (Vavilov, 1951, modified by Hawkes, 1993, 1997).

Figure 4.1. Schematic Diagram of Gene Pool Concept (Harlan & de Wet, 1971).

Figure 4.2. Schematic Diagram of A Segment of the Gene Sea (Maxted et al., 1997b).

Figure 4.3. An Ecogeographic Paradigm (Maxted et al. ,1995).

Figure 4.4. Concept of Using Layers in a GIS (Wadworth and Treweek, 1999).

Figure 5.1. An Example of a Collection Form for Forage Legume Collection (Maxted and Bisby (1989).

Figure 6.1. Gene Bank Activities at IRRI (Jackson, 1995).

Figure 7.1 The Distribution of Botanical Gardens and Botanical Diversity (Botanical Gardens Conservation International, 1989).

Figure 8.1. Types of Accessions Held in Ex Situ Collections (FAO, 1998).

Figure 8.2. Conservation of Plant Genetic Resources for Food and Agriculture in Botanical Gardens (FAO, 1998).

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Figure 11.1. Land element and position (FAO, 1990). 1 Plain level, 2 Escarpment, 3 Interfluve, 4 Valley, 5 Valley floor, 6 Channel, 7 Levee, 8 Terrace, 9 Floodplain, 10 Lagoon, 11 Pan, 12 Caldera, 13 Open depression, 14 Closed depression, 15 Dune, 16 Longitudinal dune, 17 Interdunal depression, 18 Mangrove, 19 Upper slope, 20 Midslope, 21 Lower slope, 22 Ridge, 23 Beach, 24 Beachridge 25 Rounded summit, 26 Summit, 27 Coral atoll, 28 Drainage line, 29 Coral reef, 99 Other.

Figure 11.2. Mature leaf: shape of blade of vines (IPGRI, 1997c).

Figure 11.3. Inflorescence: sex of flower of vines (IPGRI, 1997c). 1 Only male, 2 Predominantly male, 3 Male and female developed, 4 Female with straight stamens, 5 Female with reflexed stamens.

Figure 11.4. Organisational Structure of ECP/GR and its Activities During Phase V of its Operation 1994/98 (Maggioni., 1998).

Figure 12.1. Isoflor distribution map for Aegilops species, adapted from van Slageren (1994).

Figure 12.2. Distribution of Solanum tuberosum subsp. andigena and subsp. tuberosum, and S chaucha, S. juzepczkii and S. curtilobum (Hawkes, 1990).

Figure 12.3. Natural distribution of wild and cultivated Musa species (Simmonds, 1995).

Figure 12.4. Natural distribution of coffee species in Africa and Madagascar (Charrier & Berthaud, 1985).

Figure 13.1. Human population number since 1750 and projected until 2100 (Dobson, 1996).

Figure 13.2. Recent trends in human population numbers (UNEP, 1999).

Plates

Front cover. Collecting forage legume germplasm in Tadzhikistan (Photograph, Nigel Maxted).

Back cover. Diversity of potato land races in Bolivia (photograph, CIP). Plate 1. Different conservation techniques fitting together like pieces in a puzzle (Photograph, IPGRI).

Plate 2. N.I. Vavilov and co-workers, and the Vavilovian centres of crop diversity (Photograph, N.!. Vavilov Institute of Plant Industry).

Plate 3. Breeders inspecting evaluation plots in Plovdiv, Bulgaria (photograph, Nigel Maxted).

Plate 4. Summarising some ecogeographic data for Hordeum stenostachys (taken from von Bothmer et al., 1995; Photograph, IPGRI).

Plate 5. Field collecting of forages in Syria (photograph, Nigel Maxted).

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Plate 6. Conserved germplasm in long-term storage at the IRRI gene bank (Photograph, M. Jackson).

Plate 7. In vitro culture of banana (Musa) germplasm (Photograph, IPGRI).

Plate 8. The palm house at the Royal Botanic Gardens, Kew (Photograph, Royal Botanic Gardens, Kew).

Plate 9. Discussing conservation issues with farmers (photograph, IPGRI).

Plate 10. Characterisation and evaluation of Taro, Papaya and Otaheite in Java (Photograph, I. de Borhegyi, IPGRI).

Plate 11. Field documentation (Photograph, Nigel Maxted).

Plate 12. Paphiopedilum detenatii Guill., a restricted Asiatic Slipper Orchids endemic to Vietnam (Photograph, P. Cribb).

Plate 13. The new generation that need to benefit from genetic resource conservation (Photograph, Nigel Maxted).

Tables

Table 1.1. Estimated Annual Markets For Genetic Resources Products (ten Kate and Laird, 1999).

Table 1.2. Conservation Strategies and Techniques.

Table 1.3. Relative Advantages and Disadvantages of the Various Ex Situ Conservation Techniques (Maxted et at., 1997c).

Table 1.4. Annual Costs of Maintaining Cassava, Wheat and Maize Germplasm by Field Gene Bank, In Vitro Storage and Seed Conservation (Epperson et at., 1997).

Table 4.1. Sources of Information on Current Conservation Status of a Species.

Table 4.2. Examples of International Plant Conservation Legislation.

Table 4.3. Ecogeographic Data That Should Be Sought From the Literature (Maxted et at., 1995).

Table 4.4. Ecogeographic Data That Should Be Sought From the Herbarium Specimen and Gene Bank Accessions (Maxted et at., 1995).

Table 6.1. Examples of Ex Situ Storage of Germplasm in International Gene Banks (FAO, 1998).

Table 6.2. Factors causing genetic drift during regeneration of heterogeneous population (after Breeze, 1989).

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Table 7.1. Taxa "Extinct in the Wild" cultivated in British Botanic Gardens (M. Maunder, cited in Prance, 1997).

Table 8.1. Regional distribution of gene banks and accessions in ex situ collection (FAO, 1998).

Table 8.2. The Six Largest Gene Bank Ex Situ Germplasm Holdings For The Major Crops (FAO, 1998).

Table 8.3. The World's Largest National Ex Situ Storage Facilities (Adapted from FAO, 1998).

Table 12.1. Section, species and species complexes in the genus Oryza, with designated genome groups (after Vaughan, 1994; Aggarwal et al., 1997).

Table 12.2. Genera, number of species and distribution of genera within the Oryzae (after Vaughan, 1994) (Tr= tropical; Te= temperate).

Table 12.3. Classification of cultivated and wild wheats and the closely related Aegilops sect. Sitopsis species (Adapted from van Slageren, 1994).

Table 12.4. Cultivated Trifolium species (Lamont et al., 1999).

Table 12.5. A summary of the classification of Trifolium species (Zohary and Heller, 1984).

Table 12.6. Major Leucaena leucocephala Primary Gene Pool Seed Collection Holdings (Adapted from Hughes, 1998b).

Table 13.1. Indicators of the growth of global consumption of resources from 1950 to 1991 (Brown and Wyckoff~Baird 1992).

Appendices

Appendix 1. A Model for Quantifying the Threat of Genetic Erosion (Guarino, 1995).

Appendix 2. International Code of Conduct for Plant Germplasm Collecting and Transfer (FA0,1994)

Appendix 3. Checklist of Basic Collecting Equipment (Hawkes, 1980).

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Plate I. Different conservation techniques fitting together like pieces in a puzzle (Photograph, I PGRI).

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Plate 2. N.!. Vavilov and co-workers, and (he Vavilovian centres of crop diversity (Photograph, N.l . Vavilov Institute of Plant Industry) .

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Plate 3. Breeders inspecting evaluation plots in Plovdiv , Bulgaria (Photograph, Nigel Maxted).

HOldfutn .If,noJrachy.

Plate 4. Summarising some ecogeographic data for Hordeum stenostachys (taken from von Bothmer el al., 1995; Photograph, IPGRI).

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Plate 5. Field collecting of forages in Syria (Photograph, Nigel Maxted).

Plare 6. Conserved germplasm 1Il long-term storage at the IRRI gene bank (Photograph, M. Jackson).

XXlIl

Plate 7. In vitro culture of banana (Musa) germplasm (Photograph, IPGRI).

Plate 8. The palm house at the Royal Botanic Gardens, Kew (Photograph, Royal Botanic Gardens , Kew) .

XXIV

Plate 9. Discussing conservation issues with fanners (Photograph, IPGRI).

Plate lO. Characterisation and evaluation of Taro, Papaya and Otaheite in Java (Photograph, I. de Borhcgyi, IPGRI).

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Plate 11. Field documentation (Photograph, Nigel Maxted) .

Plate 12. Paphiopedilwn delenatii Guill. , a restricted Asiatic Slipper Orchids endemic to Vietnam (Photograph, P. Crihh) .

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Plate 13. The new generation that need to benefit from genetic resource conservation (Photograph, Nigel Maxted).