SummaryWe assessed the extent of representativeness of global ex situ

collections of wild relatives of cultivated potato compared to the full

range of potential diversity. Analysis was based on a systematic gap

analysis involving the largest species occurrence database of its kind

for any crop wild relative. It is concluded that significant gaps exist in

global ex situ collections as 43.8% of the species analyzed received a

high priority status for gap filling.

IntroductionGap analysis is a systematic approach to analyze the degree of ex

situ conservation of species and to place priorities on geographic

locations, species and potentially useful traits that are un- or under

secured (Maxted et al., 2008; Ramírez-Villegas et al., 2010).

Additionally, gap analysis can help to set priorities for complementary

in situ conservation.

Materials and MethodsA total of 49,164 records for 73 species of wild relatives of potato

were compiled (75.8% with coordinates), corresponding to 11,100

germplasm accessions and 37,251 reference sightings. We used a

gap analysis methodology (Maxted et al., 2008; Ramírez-Villegas et

al., 2010), including complementary metrics: (i) Sampling

Representativeness Score, (ii) Geographic Representativeness

Score, (iii) Ecoregional Representativeness Score. In turn these

scores used to calculate the Final Priority Score (FPS). MaxEnt

(Phillips et al., 2006) was selected for the purpose of estimating the

potential niche breadth of each taxon. As environmental drivers we

used 19 bioclimatic variables derived from the WorldClim database

(Hijmans et al., 2005). Maps visualizing species richness and

predicted gap density were produced using GIS and environmental

niche modelling algorithms

Figure 2. Current and potential distribution of the closest wild relatives of potato: A)

Distribution of germplasm and herbarium registers included in the analysis, B)

Species richness patterns, C) Hotspots where collecting of HPS is suggested based

on predicted species occurrence

Conclusions(i) Significant gaps exist in the representativeness of potato wild

relatives in global ex-situ collections.(ii) We propose three levels of priority for filling gaps. First level:

urgent collections of unsecured species lacking any activeaccessions in genebanks (4 HPS, 2 countries). Second level:targeted collections of the main under secured species (28HPS, 8 countries). Third level: complementary collections ofMPS.

Bibliography• Maxted N, Dulloo E, Ford-Lloyd BV, Iriondo JM, Jarvis A, et al. 2008. Gap analysis: a tool for

complementary genetic conservation assessment. Divers Distrib 14: 1018–1030.

• Ramírez-Villegas J, Khoury C, Jarvis A, Debouck DG, Guarino L. 2010. A gap analysis methodology for

collecting crop genepools: a case study with phaseolus beans. PLoS One 5: e13497.

• Phillips S, Anderson R, Schapire R. 2006. Maximum entropy modeling of species geographic

distributions. Ecol Modell 190: 231–259.

• Hijmans RJ, Cameron SE, Parra JL, Jones PG, Jarvis A. 2005. Very high resolution interpolated climate

surfaces for global land areas. Int J Climatol 25: 1965–1978.

Nora Castañeda-Álvarez1,2

Stef de Haan3

Henry Juárez3

Colin Khoury1,4

Harold Achicanoy1

Chrystian Sosa1

Vivian Bernau1

Alberto Salas3

Bettina Heider3

Reinhard Simon3

Nigel Maxted2

David Spooner5

1 International Center for Tropical Agriculture

(CIAT), Km 17, Recta Cali-Palmira, Cali, Colombia2 School of Biosciences, University of Birmingham,

Edgbaston, Birmingham, B15 2TT, UK3 International Potato Center (CIP), Lima, Peru

4 Centre for Crop Systems Analysis, Wageningen

University, Droevendaalsesteeg 1, 6708 PB

Wageningen, The Netherlands5 USDA-ARS, Vegetable Crop Research Unit,

Department of Horticulture, University of

Wisconsin, Madison, USA

(Solanum sect. Petota)

Gap analysis of the wild relatives of potato

Conserving Diversity for the Future: The CIP Genebank

Figure 1. High Priority Species (HPS) and countries where these occur

Figure 3. Priorities for gap filling and conservation by country

Figure 4. Flowers, plants and habitats of A) Solanum acaule Bitter, B) S. candolleanum Berthault, C) S. laxissimum Bitter, D) S. rhomboideilanceolatumOchoa, E) S. simplicissimum Ochoa and F) S. wittmackii Bitter. Photographs taken

by: S. de Haan

ResultsSpecies richness is highest in Peru, followed by Mexico and

Argentina (Figure 2B). A total of 32 species (43.8%) are High Priority

Species (HPS) and need to be prioritized for further collecting due to

significant gaps in ex situ collections. Such gaps are most notable in

Peru with 21 HPS in its territory, followed by followed by Mexico (4

HPS); Bolivia (3 HPS), Colombia (2 HPS), Ecuador (2 HPS) and

Argentina, Chile and Guatemala (each with 1 HPS). See: Figures 1,

2C, and 3. A total of 20 species are Medium Priority Species (MPS)

and only three species were found to require no further collection

(NFCR). Four species require urgent attention as no active

germplasm accessions are currently available in any global

collections: S. ayacuchense (PER), S. neovavilovii (BOL), S.

olmosense (PER) and S. salasianum (PER).