Hostname: page-component-78c5997874-s2hrs Total loading time: 0 Render date: 2024-11-05T14:01:30.660Z Has data issue: false hasContentIssue false
  • English
  • Français

Cowpea [Vigna unguiculata (L.) Walp.] core collection defined by geographical, agronomical and botanical descriptors

Published online by Cambridge University Press:  22 November 2007

V. Mahalakshmi ,
Q. Ng ,
M. Lawson  and
R. Ortiz
V. Mahalakshmi
Affiliation:
International Institute of Tropical Agriculture (IITA), PMB 5320, Oyo Road, Ibadan, Nigeria
Q. Ng
Affiliation:
International Institute of Tropical Agriculture (IITA), PMB 5320, Oyo Road, Ibadan, Nigeria
M. Lawson
Affiliation:
International Institute of Tropical Agriculture (IITA), PMB 5320, Oyo Road, Ibadan, Nigeria
R. Ortiz*
Affiliation:
Centro Internacional de Mejoramiento de Maíz y Trigo (CIMMYT), Apdo. Postal 6-641, 06600 Mexico, D.F, Mexico
*
*Corresponding author. E-mail: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

Cowpea is a drought-tolerant food legume grown in the savannah regions of the tropics and subtropics. The International Institute for Tropical Agriculture (IITA) holds the world collection of 15,003 cultivated cowpea from 89 countries in its genebank. In excess of 12,000 accessions were characterized for 28 agrobotanical descriptors. The entire collection was first stratified by country of origin and biological status. Land race accessions (10,227) with information on origin and characterization data were grouped using clustering procedures. The clustering analysis was based on Euclidean distances between and among accessions. Accessions within each country were then grouped hierarchically, according to their similarity. The number of clusters selected for countries varied from 2 to 20, depending on the size of collection for that country. A percentage number of accessions (5–25%) was chosen from each country, based on the size of the collection and its proximity to the centre of diversity. The number of accessions from each cluster in a country was then chosen randomly, based on the predetermined percentage. In countries where the numbers of accessions were few ( < 10), the percentage chosen from those countries would be higher and may go up to 100% to ensure that at least one accession was chosen from every country. Accessions with no characterization information were treated as a group, and accessions were chosen randomly, based on their geographical distribution. In the process of selection, 200 accessions that are known to be resistant to pests and diseases and not originally chosen through the selection processes were, nevertheless, kept as part of the core collection. Following these procedures, a total of 1701 accessions of landraces were chosen from the entire collection. Using the same procedures, a subset of 225 accessions was chosen from 1422 advanced cultivars and breeding or research lines. A third subset of 130 accessions was chosen from 838 accessions that either lack information on origin or biological status, and six accessions of wild and weedy forms from the available 64 wild and weed accessions were added. Thus a core collection of 2062 accessions of cowpea was constituted. The diversity in the core collection was similar to that of the entire collection and correlated traits that may be linked were also preserved in the core collection. This core collection of cowpea provides an opportunity for further exploitation of the cowpea germplasm for improvement of this crop.

Keywords

core collectioncowpeadescriptorsdiversitysamplingVigna unguiculata
Type
Research Article
Information
Plant Genetic Resources , Volume 5 , Issue 3 , December 2007 , pp. 113 - 119
Copyright
Copyright © NIAB 2007

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Brown, AHD (1989a) A case for core collections. In: Brown, AHD, Frankel, OH, Marshall, DR and Williams, JT (eds) The Use of Plant Genetic Resources. Cambridge: Cambridge University Press, pp. 136–156.Google Scholar
Brown, AHD (1989b) Core collections: a practical approach to genetic resources management. Genome 31: 818–824.CrossRefGoogle Scholar
Cordeiro, CMT, Morales, EAV, Ferreira, P, Rocha, DMS, Costa, IRS and Valios, ACC (1995) Towards a Brazilian core collection of cassava. In: Hodgkin, T, Brown, AHD, van Hintum, ThJL and Morales, BAV (eds) Core Collections of Plant Genetic Resources. New York: International Plant Genetic Resources Institute (IPGRI), John Wiley & Sons, pp. 155–168.Google Scholar
Erskine, W and Muehlbauer, FJ (1991) Allozyme and morphological variability, outcrossing rate and core collection formation in lentil germplasm. Theoretical and. Applied Genetics 83: 119–125.CrossRefGoogle ScholarPubMed
Frankel, OH and Brown, AHD (1984) Plant genetic resources today: a critical appraisal. In: Holden, JHW and Williams, JT (eds) Crop Genetic Resources: Conservation and Evaluation. London: George Allen & Unwin, pp. 249–257.Google Scholar
Hannan, RM, Kaiser, WJ and Muehlbauer, FJ (1994) Development and Utilization of the USDA Chickpea Germplasm Core Collection. Agronomy Abstracts 1994. Madison, Wisconsin: American Society of Agronomy, p. 217.Google Scholar
Harlan, JR (1972) Genetics of disaster. Journal of Environmental Quality 1: 212–215.CrossRefGoogle Scholar
Holbrook, CC, Anderson, WF and Pittman, RN (1993) Selection of core collection from the U.S. germplasm collection of peanut. Crop Science 33: 859–861.CrossRefGoogle Scholar
Huamán, Z, Aguilar, C and Ortiz, R (1999) Selecting a Peruvian sweet potato core collection on the basis of morphological, ecogeographical and disease reaction data. Theoretical and Applied Genetics 98: 840–844.CrossRefGoogle Scholar
Huamán, Z, Ortiz, R and Gómez, R (2000a) Selecting a Solanum tuberosum subsp. Andigena core collection according to morphological, geographical, disease and pest descriptors. American Journal of Potato Research 77: 183–190.CrossRefGoogle Scholar
Huamán, Z, Ortiz, R, Zhang, DP and Rodríguez, F (2000b) Isozyme analysis of entire and core collections of Solanum tuberosum spp. andigena potato cultivars. Crop Science 40: 273–276.CrossRefGoogle Scholar
IBPGR (1983) Cowpea Descriptors. Rome: International Board of Plant Genetic Resources.Google Scholar
Knüpffer, H and van Hintum, ThJL (1995) The barley core collection: an international effort. In: Hodgkin, T, Brown, AHD, van Hintum, ThJL and Morales, BAV (eds) Core Collections of Plant Genetic Resources. New York: International Plant Genetic Resources Institute (IPGRI), John Wiley & Sons, pp. 171–178.Google Scholar
Mahalakshmi, V, van Hintum, ThJL and Ortiz, R (2003) Enhancing germplasm utilization to meet specific users' needs through interactive stratified core selections. Plant Genetic Resources Newsletter 136: 14–22.Google Scholar
Ng, NQ (1995) Cowpea. In: Smart, J and Simmonds, NW (eds) Evolution of Crop Plants. 2nd edn. Burnt Mill, Harlow, UK: Longman Scientific and Technical, pp. 326–332.Google Scholar
Ortiz, R, Ruiz-Tapia, EN and Mújica-Sánchez, A (1998) Sampling strategy for a core collection of Peruvian quinoa germplasm. Theoretical and Applied Genetics 96: 475–482.CrossRefGoogle ScholarPubMed
Padulosi, S (1993) Genetic diversity, taxonomy, and ecogeographic survey of the wild relatives of cowpea (V. unguiculata). PhD Thesis, University of Louvain-La Neuve, Belgium.Google Scholar
SAS Institute (1989) SAS/SAT User Guide version 6. 4th edn. Cary, North Carolina: SAS Institute.Google Scholar
Shannon, CE and Weaver, W (1946) The Mathematical Theory of Communication. Urbana: University of Illinois Press.Google Scholar
Singh, BB (2002) Breeding cowpea varieties for resistance to Striga gesnerioides and Alectra vogelii. In: Fatokun, CA, Tarawali, SA, Singh, BB, Kormawa, PM and Tamo, M (eds) Challenges and Opportunities for Enhancing Sustainable Cowpea Production. Ibadan, Nigeria: International Institute of Tropical Agriculture, pp. 154–163.Google Scholar
Tohme, J, Jones, P, Beebe, S and Iwanaga, M (1995) The combined use of agroecological and characterization data to establish the CIAT Phaseolus vulgaris core collection. In: Hodgkin, T, Brown, AHD, van Hintum, ThJL and Morales, BAV (eds) Core Collections of Plant Genetic Resources. New York: International Plant Genetic Resources Institute (IPGRI), John Wiley & Sons, pp. 95–108.Google Scholar
Upadhyaya, HD, Bramel, PJ and Singh, S (2001) Development of a chickpea core subset using geographic distribution and quantitative traits. Crop Science 41: 206–210.CrossRefGoogle Scholar
Upadhyaya, HD, Gowda, CLL, Pundir, RPS, Goppal Reddy, V and Singh, S (2006) Development of core subset of finger millet germplasm using geographical origin and data on 14 quantitative traits. Genetic Resources and Crop Evolution 53: 679–685.CrossRefGoogle Scholar
Upadhyaya, HD, Ortiz, R, Bramel, PJ and Singh, S (2003) Development of a groundnut core collection using taxonomical geographical descriptors. Genetic Resources and Crop Evolution 50: 139–148.CrossRefGoogle Scholar
van Hintum, ThJL (1999) The core selector, a system to generate representative selections of germplasm collections. Plant Genetic Resources Newsletter 118: 64–67.Google Scholar
Ward, JH (1963) Hierarchical grouping to optimize an objective function. Journal of American Statistical Association 58: 236–244.CrossRefGoogle Scholar