Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-11-22T05:29:21.893Z Has data issue: false hasContentIssue false
  • English
  • Français

Excess heterozygosity and scarce genetic differentiation in the populations of Phoenix dactylifera L.: human impact or ecological determinants

Published online by Cambridge University Press:  20 October 2008

Sakina Elshibli  and
Helena Korpelainen
Sakina Elshibli
Affiliation:
Department of Applied Biology, PO Box 27, FI-00014 University of Helsinki, Finland
Helena Korpelainen*
Affiliation:
Department of Applied Biology, PO Box 27, FI-00014 University of Helsinki, Finland
*
*Corresponding author. E-mail: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

Extensive research has been conducted on the characterization of hundreds of date palm (Phoenix dactylifera L.) cultivars worldwide. However, the population genetics of date palms has never been studied. In this study, we collected 200 individuals from 19 populations of different geographical locations in Sudan. The collection sites were grouped according to the type of dates (date palm fruits) that dominates in the area. Ten microsatellite markers were used to investigate the genetic diversity within and among populations and the correlation between the genetic and geographical distances. The tested microsatellite markers showed a high level of polymorphism. A total of 261 alleles were detected at the ten loci. The overall mean value of fixation indices equalled − 0.163, which shows the presence of excess heterozygosity. However, the χ2 tests conducted for every locus in each population indicated no significant deviation from the Hardy–Weinberg equilibrium. The analyses of molecular variance exhibited that about 95% of the total genetic variation existed within populations, while significant differentiation within the type groups could be detected. Although significant isolation by distance (r2 = 0.552, P < 0.05) was detected by a Mantel test, it seems that the spatial effect has become complicated as a result from the exchange and introduction of different kinds of plant materials by date palm growers and traders, as well as seed dispersal. This complexity was clearly apparent in the weak clustering relationships among most of the tested populations.

Keywords

Phoenix dactyliferaheterozygositygeneticdifferentiationmicrosatellite markerspopulations
Type
Research Article
Information
Plant Genetic Resources , Volume 7 , Issue 2 , August 2009 , pp. 95 - 104
Copyright
Copyright © NIAB 2008

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

Adawy, SS, Hussein, EHA, Ismail, SEME and El-Itriby, HA (2006) Genomic diversity in date palm (Phoenix dactylifera L.) as revealed by AFLPs in comparison to RAPDs and ISSRs In: Abstracts 0f 3rd International Date Palm Conference, Abu Dhabi, United Arab Emirates, 19–21 February 2006.Google Scholar
Ahmed, M and Ali, N (1960) Effect of different pollens on the physical and chemical characters and ripening of date fruit. Punjab Fruit Journal 23: 10–11.Google Scholar
Al-Khalifah, NS and Askari, E (2003) Molecular phylogeny of date palm (Phoenix dactylifera L.) cultivars from Saudi Arabia by DNA fingerprinting. Theoretical and Applied Genetics 107: 1266–1270.CrossRefGoogle ScholarPubMed
Baaziz, M, Majourhat, K and Bendiab, K (2000) Date palm culture in the Maghreb countries: constraints and scientific research. Proceedings of the Date Palm International Symposium, Windhoek, Namibia, 22–25 February, pp. 306–311.Google Scholar
Babiker, M and Gudmundsson, A (2004) The effects of dykes faults on groundwater flow in an arid land: The Red Sea Hills, Sudan. Journal of Hydrology 279: 256–273.CrossRefGoogle Scholar
Billotte, N, Marseilla, CN, Brottier, P, Noyer, JL, Jacquemoud-Collet, JP, Moreau, C, et al. , (2004) Nuclear microsatellite markers for the date palm (Phoenix dactylifera L.): characterisation, utility across the genus Phoenix and in other palm genera. Molecular Ecology Notes 4: 256–258.CrossRefGoogle Scholar
Cao, BR and Chao, CT (2002) Identification of date cultivars in California using AFLP markers. HortScience 37: 966–968.Google Scholar
Chao, CT and Krueger, RR (2007) The date palm (Phoenix dactylifera L.): overview of biology, uses and cultivation. HortScience 42: 1077–1082.Google Scholar
El-Assar, AM, Krueger, RR, Devanad, PS and Chao, CT (2005) Genetic analysis of Egyptian date (Phoenix dactylifera L.) accessions using AFLP markers. Genetic Resources and Crop Evolution 52: 601–607.Google Scholar
Elhoumaizi, MA, Saaidi, M, Oihabi, A and Cilas, C (2002) Phenotypic diversity of date-palm cultivars (Phoenix dactylifera L.) from Morocco. Genetic Resources and Crop Evolution 49: 483–490.CrossRefGoogle Scholar
Elshibli, S and Korpelainen, H (2008) Microsatellite markers reveal high genetic diversity in date palm (Phoenix dactylifera L.) germplasm from Sudan. Genetica (in press). DOI 10.1007/s10709-007-9232-8.Google Scholar
Excoffier, L, Laval, G and Schneider, S (2005) Arlequin ver. 3.0: An integrated software package for population genetics data analysis. Evolutionary Bioinformatics 1: 47–50.Google Scholar
Excoffier, L, Smouse, PE and Quattro, M (1992) Analysis of molecular variance inferred from metric distances among DNA haplotypes: application to human Mitochondrial DNA restriction data. Genetics 131: 479–491.CrossRefGoogle ScholarPubMed
Felsentein, J (1985) Confidence limits on phylogenies: an approach using the bootstrap. Evolution 39: 783–791.CrossRefGoogle Scholar
Felsentein, J (2005) PHYLIP (Phylogeny Interference Package) version. 3.6. Distributed by the author. Department of Genome Sciences, University Washington, Seattle.Google Scholar
Hamrick, JL, Godt, MJW and Sherman-Broyles, SL (1992) Factors influencing levels of genetic diversity in woody plant species. New Forests 6: 95–124.CrossRefGoogle Scholar
Hulme, M (1990) The changing rainfall resources of Sudan. Transactions of the Institute of British Geographers 15: 21–34.Google Scholar
Jaradat, AA and Zaid, A (2004) Quality traits of date palm fruits in a center of origin and center of diversity. Food, Agriculture and Environment 2: 208–217.Google Scholar
Loveless, MD and Hamrick, JL (1984) Ecological determinants of genetic structure in plant populations. Annual Review of Ecology and Systematics 15: 65–95.CrossRefGoogle Scholar
Li, CC and Horwitz, DG (1953) Some methods of estimating the inbreeding coefficient. American Journal of Human Genetics 5: 107–117.Google ScholarPubMed
Rousset, F (1997) Genetic differentiation and estimation of gene flow from F-statistics under isolation by distance. Genetics 145: 1219–1228.Google Scholar
Rice, WR (1989) Analysing tables of statistical tests. Evolution 43: 223–225.Google Scholar
Mantel, N (1967) The detection of disease clustering and a generalized regression approach. Cancer Research 27: 209–220.Google Scholar
Nei, M (1972) Genetic distance between populations. American Naturalist 106: 283–292.Google Scholar
Nixon, RW (1950) Imported cultivars of dates in the United States USDA Circular No. 834: 144.Google Scholar
Nixon, RW (1967) Date culture in Sudan, Date Growers' Institute Report 44: 9–14.Google Scholar
Nixon, RW and Carpenter, JB (1978) Growing dates in the United States US Department of Agriculture, Agriculture Information Bulletin No. 207: USDA. Technical Document, p. 63.Google Scholar
Osman, AMA (1984) The performance of date palms in the Sudan. Acta Horticulturae 143: 231–237.CrossRefGoogle Scholar
Osman, AMA (2001) Development of date palm culture in Republic of Sudan Paper presented at a workshop on date palm culture and dates production in Republic of Sudan. Date Palm Research and Development Network, Khartoum, Sudan, 22–17 August..Google Scholar
Sedra, MH, Lashermes, P, Trouslot, P, Combes, M and Hamon, S (1998) Identification and genetic diversity analysis of date palm (Phoenix dactylifera L.) varieties from morocco using RAPD markers. Euphytica 103: 75–82.CrossRefGoogle Scholar
Soliman, SS, Ali, BA and Ahmed, MMM (2003) Genetic comparisons of Egyptian date palm cultivars (Phoenix dactylifera L.) by RAPD-PCR. African Journal of Biotechnology 2: 86–87.Google Scholar
Trifi, M, Rhouma, A and Marrakchi, M (2000) Phylogenetic relationships in Tunisian date-palm (Phoenix dactylifera L.) germplasm collection using DNA amplification fingerprinting. Agronomie 20: 665–671.CrossRefGoogle Scholar
United Nations Environment Programme(2007) Natural disasters and desertification. In: Sudan – Post – Conflict Environmental Assessment, Nairobi, Kenya. ISBN: 978-92-807-2702-9, pp. 56-69.Google Scholar
Wright, S (1969) Evolution and genetics of populations. The Theory of Gene Frequencies, vol. 2. Chicago: University of Chicago Press.Google Scholar
Wrigley, G (1995) Date palm (Phoenix dactylifera L.). In: Smartt, J and Simmonds, NW (eds) The Evolution of Crop Plants. London: Longman, pp. 399–403.Google Scholar
Zaid, A and de Wet, PF (2002a) Botanical and systematic description of the date palm. In: Zaid, A (ed.) Date Palm Cultivation. FAO Plant Production and Protection Paper No. 156. Rome: Food and Agriculture Organisation of the United Nations, pp. 1–28.Google Scholar
Zaid, A and de Wet, PF (2002b) Origin, geographical distribution and nutritional values of date palm. In: Zaid, A (ed.) Date Palm Cultivation. FAO Plant Production and Protection Paper no. 156, Rome: Food and Agriculture Organisation of the United Nations, pp. 29–44.Google Scholar
Zaid, A and de Wet, PF (2002c) Date palm propagation. In: Zaid, A (ed.) Date Palm cultivation. FAO Plant Production and Protection Paper No. 156. Rome: Food and Agriculture Organisation of the United Nations, pp. 73–89.Google Scholar
Zaid, A and de Wet, PF (2002d) Pollination and bunch management. In: Zaid, A (ed.) Date Palm Cultivation. FAO Plant Production and Protection Paper No. 156. Rome: Food and Agriculture Organisation of the United Nations, pp. 145–175.Google Scholar
Zaid, A, de Wet, PF, Djebri, M and Oihabi, A (2002) Diseases and pests of date palm. In: Zaid, A (ed.) Date Palm Cultivation. FAO Plant Production and Protection Paper No. 156. Rome: Food and Agriculture Organisation of the United Nations, pp. 227–242.Google Scholar
Zehdi, S, Trifi, M, Billotte, N, Marrakchi, M and Pintaud, JC (2004a) Genetic diversity of Tunisian date palms (Phoenix dactylifera L.) revealed by nuclear microsatellite polymorphism. Hereditas 141: 278–287.Google Scholar
Zehdi, S, Sakka, H, Rhouma, A, Ould Mohamed Salem, A, Marrakchi, M and Trifi, M (2004b) Analysis of Tunisian date palm germplasm using simple sequence repeat primers. African Journal of Biotechnology 3: 215–219.CrossRefGoogle Scholar
Zhang, X, Korpelainen, H and Li, C (2006) Microsatellite variation of Quercus aquifolioides populations at varying altitudes in the Wolong natural reserve of China. Silva Fennica 40: 407–415.Google Scholar