Plant Genetic Resource Gap Analysis: targeting CWR for in situ and ex situ conservation

2. Plant Genetic Resource Gap Analysis: targeting CWR for in situ and ex situ conservation Nigel Maxted DRAFT THOUGHTS

3. Talk Objectives • Need to improve conservation through better prioritisation • What is ‘Gap Analysis’ and how to apply for PGR? • Proposed methodology for discussion • Exemplar: Cowpea and its relative (Vigna Savi) in Africa

4. The need for increased efficiency of conversation “Develop, where necessary, guidelines for the selection, establishment and management of protected areas or areas where special measures need to be taken to conserve biological diversity.” Article 8 - CBD (UNCED, 1992)

5. What is ‘gap analysis’? • So called ‘Gap analysis’ was initially associated with Margules et al. as a conservation evaluation technique • To identifies areas in which selected elements of biodiversity are represented then by comparison with protected areas identify under-represented areas or gaps (Margules, 1989) • Largely applied to indigenous forests particularly on small islands rich in endemic species

6. Goal of Plant Genetic Conservation • “95% of all the alleles at a random locus occurring in the target population with a frequency greater than 0.05” Marshall and Brown (1975) • Equates to approx. 50 sites x 100 plant collections or 5,000 individuals in a genetic reserve • Post-CBD add “using a range of conservation techniques”, which takes account of complementary conservation

7. Has this goal been achieved? FAO (1998)

8. Is ex situ / in situ conservation working effectively? • PGR ex situ NO, except for major crops! • FAO figures for gene bank holdings show that for minor crops few species meet needs but some are over collected • PGR in situ NO! • Heywood review of genetic reserves approx 10 genetic reserves for all crops • On-farm projects possibly 10-20 project and all lack consistency of funding – no sustainability • Traditional gap analysis techniques may be adapted to use in the PGR context

9. Gap Analysis Methodology • Burley (1988) identified four steps in traditional gap analysis: • identify and classify biodiversity • locate areas managed primarily for biodiversity • identify biodiversity that is underrepresented in those managed areas, and • set priorities for conservation action. • Still applied to ecosystem conservation, can we adapt for plant genetic conservation

10. Adaptation of Gap Analysis for PGR Conservation • Not just dealing with ecosystem conservation in protected areas • Conserving genetic as well as taxonomic diversity • Complementary conservation, two strategies (in situ and ex situ) and a range of techniques for each • Linking conservation to utilisation

11. PGR Gap Analysis Methodology • Essentially PGR gap analysis involves: • Comparison of range of diversity with • Conserved sample of that range of diversity • The ‘analysis’ comes in the comparison • Does the sample provide a efficient representation of the range of diversity? • The diversity not represented in the sample is the gap!

12. PGR Gap Analysis Methodology In the PGR context implies a series of steps: Step 1:Circumscription of target taxon and target area Step 2: Assessment of natural in situ diversity 2a - Taxonomic Diversity Assessment 2b -Genetic Diversity Assessment 2c -Ecogeographic Diversity Assessment 2d - Threat Assessment Step 3:Assessment of current conservation strategies 3a - In situ techniques 3b - Ex situ techniques Step 4: Setting priorities for conservation action 4a - In situ conservation priorities 4b - Ex situ conservation priorities

13. When to apply PGR GA? • Once target taxon selected? • As part of ecogeographic study? • Before application of conservation strategy? • When reviewing conservation strategy?

14. Step 1:Circumscription of target taxon and target area • Defined by project commission for conservation action • Breadth of target taxon • Breadth of target area

15. Step 2: Assessment of natural in situ diversity – 2a Taxonomic Diversity • Need to select a classification • List of accepted taxa • Descriptive data • Distributional data • How to find the appropriate classification • Specialist publications • Taxon experts • Various media searches (International Legume Database and Information Service (http://www.ildis.org/) or Species 2000 (http://www.sp2000.org/)

16. 2a Taxonomic Diversity: Vigna • Classification of African Vigna • Marchal et al. (1978) + subsequently described taxa • Pasquet (2001) conception of V. unguiculata • Tomooka et al. (2002) conception of subgenus Ceratotropis. • 61 species and 56 subspecific taxa for Africa

17. 2b -Genetic Diversity Assessment • Need to understand patterns of genetic diversity for target taxa • Is it correlated with ecogeography or not?

18. 2b -Genetic Diversity Assessment

19. Comparison of Genetic diversity with Ecogeography • UK study of UK native plant species: Beta vulgaris subsp. maritima (L.) Arcang., Brassica rapa L., Calluna vulgaris (L.) Hull, Chamaemelum nobile (L.) All. and Trifolium repens L. • Correlated - Chamaemelum nobile, Calluna vulgaris, Brassica rapa • No obvious correlation -Beta vulgaris subsp. maritima and Trifolium repens • Possible association with introgression with crops • In the absence of genetic diversity information, ecogeographic data provides the best approximation!

20. 2b -Genetic Diversity Assessment • Too expensive to collate de novo • Review what is available via a web search

21. 2b -Genetic Diversity Assessment: Vigna • Entirely restricted to cowpea gene pool studies • Eleven subspecies plus several varieties • Pasquet (1993a, 1993b, 1997) • Coulibaly et al. (2002) • Is this situation typical?

22. 2c -Ecogeographic Diversity Assessment • In the absence of genetic diversity data ecogeographic data provides the most appropriate proxy • Established models for ecogeographic data collection, analysis and application, e.g. Maxted at al. (1995, etc.)

23. 2c -Ecogeographic Diversity Assessment: Vigna • Based on 7,300 herbarium specimens and 1,912 germplasm accessions • Herbarium specimens from 30 herbaria in Africa, Europe and North America • Germplasm accessions from 4 gene banks (IITA, ILRI, CIAT and Jardin Botanique Nationale de Belgique) • Basis of analysis

24. 2c -Ecogeographic Diversity Assessment: Vigna Density of collections in 200 km x 200 km grid cells

25. 2c -Ecogeographic Diversity Assessment: Vigna Observed geographic area of distribution calculated using the Circular Area statistic with a 50km radius (CA50)

26. 2c -Ecogeographic Diversity Assessment: Vigna Species richness per degree latitude

27. 2c -Ecogeographic Diversity Assessment: Vigna Species richness per 50m altitude class

28. 2c -Ecogeographic Diversity Assessment: Vigna Species richness of Vigna in 20 km x 20 km grid cells smoothed using inverse distance weighting and a window of 200 km radius

29. 2c -Ecogeographic Diversity Assessment: Vigna Absolute species richness based on herbarium collections only in 200 km x 200 km grid cells

30. 2c -Ecogeographic Diversity Assessment: Vigna Absolute species richness of germplasm collections only in 200 km x 200 km grid cells

31. 2c -Ecogeographic Diversity Assessment: Vigna Predicted distribution of species richness

32. 2d - Threat Assessment • Media reports • Target taxon specific • Region or nation specific • IUCN categories • Need to understand is incomplete

33. IUCN Assessment for Vigna

34. Taxon Vulnerability Assessment • IUCN Red Listing is best assessment, but not always sufficient data • Can approximate vulnerability to genetic diversity and even extinction using seven criteria: • rarity • distributional range • gross representation in ex situ collections • geographic coverage of ex situ collections • coverage of ex situ collections • utility • extinction assessment • Crude measure

35. Taxon Vulnerability Assessment Analysis • Rarity - estimated from the total number of herbarium specimens and gene bank accessions of each taxon • Distributional range – calculated from a radius around each collecting locality and then by merging the resulting circles calculates the total distributional area • Gross representation in ex situ collections - numbers of gene bank accessions should be approximately 10% of the number of herbarium specimens, any species with a lower proportion are vulnerable

36. Taxon Vulnerability Assessment Analysis • Geographic coverage of ex situ collections - compares the geographic distribution of ex situ conserved accessions with the entire range of geographic distribution • Intra-species coverage of ex situ collections – compares ex situ sampling with actual distribution • Utility – Within the genetic resource context it is entirely viable to include a use factor

37. Taxon Vulnerability Assessment Analysis • Extinction assessment - Solow’s equation (Solow, 1993) as proposed by Burgman et al. (1995), which uses a combination • Collection timing • Frequency • Specimen numbers • Each one generates a numeric score of 0 – 10 • Scores are calculated for taxa

38. Taxon Vulnerability Assessment Analysis: Vigna

39. Step 3:Assessment of current conservation strategies • In situ • Genetic reserve of CWR • On-farm of landraces • Ex situ • Seed bank of germplasm • Other techniques ?

40. 3a - In situ techniques / reserve • No active genetic reserves for Vigna species • Passive conservation which is coincident with existing protected area • Likely to establish reserve in existing protected area

41. MAB Protected Areas in Africa

42. 3a - In situ techniques / reserve • MAB not only protected areas, many other see IUCN listing of National Parks and Protected Areas • Few countries have adequate represented of protected areas like Kenya, Guinea and South Africa • 54% of wild species Vigna are predicted to have populations present in at least one protected area • In reality, the number and ecogeographic diversity of African Vigna species makes in situ conservation the only practical conservation option for adequate conservation of the broadest gene pool • Need to match distribution to existing protected areas

43. 3a - In situ techniques / on-farm • Find by literature / media / internet review • Cowpea (V. unguiculata) is included in IPGRI’s current on-farm conservation project in Burkina Faso (Jarvis and Ndungứ-Skilton, 2000) • Shea project in Uganda includes Bambara groundnut (Vigna subterranea) • Community Technology Development Trust project in Zimbabwe includes V. subterranea and V. unguiculata (Odero, 2001) • But no systematic on-farm conservation of Vigna in Africa

44. 3b - Ex situ techniques • Review of gene bank holdings, SINGER, EURISCO, but little help for Africa

45. 3b - Ex situ techniques • Regression of Vigna species against herbarium specimens and gene bank accessions from each country Results indicate Botswana, Namibia, South Africa and Swaziland were over-collected, while Angola, Burundi, Cameroon, Democratic Republic of the Congo, Djibouti, Nigeria, Tanzania and Zambia remain under-collected.

46. Step 4: Setting priorities for conservation action • Having provided • The best possible picture of in situ natural diversity • A review of current in situ and ex situ conservation actions • Comparison of the two identifies ‘Gaps’

47. 4a - In situ conservation priorities • Highest concentration of taxa in three hotspots of Vigna species richness • around the Great Lakes • the southern tip of Lake Tanganyika • the Cameroon Highlands • But crude species richness can give a false impression

48. 4a - In situ conservation priorities Complementarity analysis

49. 4a - In situ conservation priorities

50. 4a - In situ conservation priorities Areas of Africa where in situVigna conservation action is required