Abstract
Poor reproductive development in yams (Dioscorea spp.) has often been attributed to the polyploid nature of the crop. In this study, flow cytometry was used to determine the ploidy level of 53 accessions of Dioscorea alata, mostly from West African countries, Chad and Puerto Rico. Nuclei were isolated from young leaf material and stained with DAPI(4,6-diamidino-2-phenylindole). The nuclear genome size (2C) was measured as an indicator of the ploidy level. Dioscorea rotundata genotypes with known ploidy levels were used as standards. The results showed that the majority of plants were hexaploid (84.9%) with a smaller percentage of tetraploids (15.1%). A higher number of male plants were hexaploid than tetraploids. This is at variance with earlier findings, which reported that hexaploid male plants are rare. Higher ploidy levels were not directly related to sparse or erratic flowering as previously reported as profuse flowering occurred in some male hexaploid accessions. These findings have important implications for yam breeding in relation to yam genetic resources.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Abraham, K., 1998. Occurrence of hexaploid males in Dioscorea alata L. Euphytica 99: 5–7.
Abraham, K. & P.G. Nair, 1991. Polyploidy and sterility in relation to sex in Dioscorea alata L. Genetica 83: 93–97.
Coursey, D.G., 1967. Yams. Longman, London.
Dansi, A., H.D. Mignouna, M. Pillay & S. Zok, 2000. Ploidy level of some cultivated yams (Dioscorea cayenensis-Dioscorea rotundata complex) from Cameroon as determined by flow cytometry. Euphytica 119: 301–307.
Dansi, A., M. Pillay, H.D. Mignouna, F. Mondeil & O. Dainou, 2001. Ploidy level of the cultivated yams (Dioscorea cayenensis-Dioscorea rotundata complex) from Benin Republic determined by chromosome counting and flow cytometry. African Crop Science Journal 8: 355–364.
De Laat, A.M.M.,W. Göhde & M.J.D.C. Vogelzang, 1987. Determination of ploidy level of single plants and plant populations by flow cytometry. Plant Breeding 99: 303–307.
Dessauw, D., 1988. Etude des facteurs de la sterilité du bananier (Musa spp.) et des relations cytotaxonomiques entre M. acuminata et M. balbisiana Colla. Fruits 43: 539–700.
Dolezel, J., M. Dolezelova & F.J. Novak, 1994. Nuclear DNA amount in diploid bananas (Musa acuminata and M. balbisiana) Biologia Plantarum 36: 351–357.
Dolezel, J., 1997. Flow Cytometry: Principles and Applications in Mutation Breeding. 15th IAEA/FAO Interregional Training Course on Advances in Technologies for Induced Mutations in Crops, May 20-June 27, 1997, Olomouc, Czech Republic, 30 p.
Dolezel, J., M.A. Lysak, I. van de Houwe, M. Dolezelova & N. Roux, 1998. Use of flow cytometry for rapid ploidy determination in Musa species. Infomusa 6(1): 6–9.
Egesi, C.N., R. Asiedu & J.K. Egunjobi, 2001. Flowering in yams (Dioscorea spp.). Proceedings of the Seventh Triennial Symposium of the International Society for Tuber and Root Crops - Africa Branch, Cotonou, Benin, October 11- 17, 1998, pp. 434–437.
Essad, S., 1984. Variation géographique des nombres chromosomiques de base et polyploï die dans le genre Dioscorea, à propos du dénombrement des espè ces transversa Brown, pilosiuscula bert. et trifida L. Agronomie 4: 611–617.
Gamiette, F., F. Bakry & G. Ano, 1999. Ploidy determination of some yam species (Dioscorea spp.) by flow cytometry and conventional chromosomes counting. Genet Res & Crop Evol 46: 19–27.
Hahn, S.K., 1995. Yams: Dioscorea spp. (Dioscoreaceae). In: J. Smartt & N.W. Simmonds (Eds.), Evolution of Crop Plants, pp. 112–120. Longman Scientific & Technical, UK.
Hamon, P., J.P. Brizard, J. Zoundjihekpon, C. Duperray & A. Borge, 1992. Etude des index d'ADN de huit espè ces d'ignames (Dioscorea spp.) par cytométrie en flux. Can J Bot 70: 996–1000.
IITA, 1996. Annual Report. International Institute of Tropical Agriculture, Ibadan, Nigeria, pp. 40–43.
Martin, F.W. & S. Ortiz, 1963. Chromosome numbers and behaviour in some species of Dioscorea. Cytologia 28: 96–101.
Martin, F.W. & S. Ortiz, 1966. New chromosome numbers in some Dioscorea species. Cytologia 31: 105–107.
Miè ge, J., 1954. Nombre chromosomique et répartition géographique de quelques plantes tropicales et equatorials. Rev Cytol Biol Végét 15: 312–348.
Mignouna, H.D., N.T.H. Ellis, M.R. Knox, R. Asiedu & Q.N. Ng, 1998. Analysis of genetic diversity in Guinea yams (Dioscorea spp.) using AFLP fingerprinting. Tropical Agriculture (Trinidad) 75(2): 224–229.
Ramachandran, K., 1968. Cytological studies in Dioscoreaceae. Cytologia 33: 401–410.
Tenkouano, A., J.H. Crouch, H.K. Crouch & D. Vuylsteke, 1998. Ploidy determination in Musa germplasm using pollen and chloroplast characteristics. Hortscience 33(5): 889–890.
Terauchi, R., V.A. Chikaleke, G. Thottappilly & S.K. Hahn, 1992. Origin and phylogeny of Guinea yam as revealed by RFLP analysis of chloroplast DNA and nuclear ribosomal DNA. Theor Appl Genet 83: 743–751.
Vandenhout, H., R. Ortiz, D. Vuylsteke, R. Sweenen & K.V. Bai, 1995. Effect of ploidy on stomatal and other quantitative traits in plantain and banana hybrids. Euphytica 83: 117–122.
van Duren, M., R. Morpugo, J. Dolezel & R. Afza, 1996. Induction and verification of autotetraploids in diploid banana (Musa acuminata) by in vitro techniques. Euphytica 88: 25–34.
Zoundjihekpon, J., S. Essad & B. Toure, 1990. Dénombrement chromosomique dans dix groupes variétaux du complexe Dioscorea cayenensis-rotundata. Cytologia 55: 115–120.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Egesi, C., Pillay, M., Asiedu, R. et al. Ploidy analysis in water yam, Dioscorea alata L. germplasm. Euphytica 128, 225–230 (2002). https://doi.org/10.1023/A:1020868218902
Issue Date:
DOI: https://doi.org/10.1023/A:1020868218902