The crop wild relatives of potato have been largely and successfully used in breeding to acquire agronomical attributes that can help the cultivated potato to be more resistant against pest, diseases and extreme environmental conditions. Assessing the representativeness of these species in genebanks, is a fundamental step to secure these genetic resources for plant breeding and future availability of this crop. Poster prepared for the International Potato Center (CIP) Board of Trustees meeting, December 2014

1. Summary
We 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.
Introduction
Gap 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 Methods
A 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 active
accessions in genebanks (4 HPS, 2 countries). Second level:
targeted collections of the main under secured species (28
HPS, 8 countries). Third level: complementary collections of
MPS.
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, Colombia
2 School of Biosciences, University of Birmingham,
Edgbaston, Birmingham, B15 2TT, UK
3 International Potato Center (CIP), Lima, Peru
4 Centre for Crop Systems Analysis, Wageningen
University, Droevendaalsesteeg 1, 6708 PB
Wageningen, The Netherlands
5 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. rhomboideilanceolatum
Ochoa, E) S. simplicissimum Ochoa and F) S. wittmackii Bitter. Photographs taken
by: S. de Haan
Results
Species 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).