Abstract
Intra- and inter-specific variations in the nuclear DNA of Triticum dicoccoides Körn. (2n = 28, genome constitution AABB) and T. araraticum Jakubz. (2n = 28, AAGG), wild species, respectively, of the Emmer and Timopheevi group, were studied by restriction fragment length polymorphism (RFLP) analysis. Total DNAs of 32 T. dicoccoides and 24 T. araraticum accessions, collected from throughout the distribution areas of these species, were treated with two 6-bp cutters and hybridized with 30 nuclear DNA clones as probes to detect RFLPs. A total of 167 hybrid bands were observed per accession. All the enzyme-probe combinations showed RFLPs between accessions. The average genetic distance between the T. dicoccoides accessions was 0.0135 ± 0.0031 and that between the T. araraticum accessions 0.0036 ± 0.0015, indicative of about a four-fold intraspecific variation in T. dicoccoides as compared to T. araraticum in terms of genetic distance. No significant genetic differentiation was found for the geographical populations of these species, the genetic distance between the two species being 0.0482 ± 0.0022. The interspecific divergence corrected for intraspecific divergence was 0.0395, about three times that for T. dicoccoides and 11 times that for T. araraticum. The results show that in the wild state the Emmer and Timopheevi groups are clearly differentiated and that T. dicoccoides has much greater variation than T. araraticum, suggesting a relatively recent origin for the latter and therefore a diphyletic origin for these species.
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References
Jiang J, Gill BS (1994) Different species-specific chromosome translocations in Triticum timopheevii and T. turgidum support the diphyletic origin of polyploid wheats. Chromosome Res 2:59–64
Kihara H (1924) Cytologische und genetische Studien bei wichtigen Getreidearten mit besonderer Rücksicht auf das Verhalten der Chromosomen und die Sterilität in den Bastarden. Mem Coll Sci Kyoto Imp Univ Series B, 1:1–200
Kihara H (1944) Discovery of the DD-analyser in wheat (in Japanese). Agr Hort Tokyo 19:889–890
Kihara H (1963) Nucleus and chromosome substitution in wheat and Aegilops. II. Chromosome substitution. Seiken Ziho 15:13–23
Liu YG, Mori N, Tsunewaki K (1990) Restriction fragment length polymorphism (RFLP) analysis in wheat. I. Genomic DNA library construction and RFLP analysis in common wheat. Jpn J Genet 65:367–380
McFadden ES, Sears ER (1946) The origin of Triticum spelta and its free-threshing hexaploid relatives. J Hered 37:81–89, 107–116
Nei M (1987) Molecular evolutionary genetics. Columbia University Press, New York
Noda K, Koulin G (1989) Chromosome structural changes and their role in the evolution of tetraploid wheats. Genome 32:257–261
Ogihara Y, Tsunewaki K (1988) Diversity and evolution of chloroplast DNA in Triticum and Aegilops as revealed by restriction fragment analysis. Theor Appl Genet 76:321–332
Sachs L (1953) Chromosome behavior in species hybrids with Triticum timopheevi. Heredity 7:49–58
Sambrook J, Fritsch EF, Maniatis T (1989) Molecular cloning (2nd ed). Cold Spring Harbor Laboratory, Cold Spring Harbor, New York
Sears ER (1966) Nullisomic-tetrasomic combinations in hexaploid wheat. In: Riley R, Lewis KR (eds) Chromosome manipulations and plant genetics. Oliver and Boyd, Edinburgh, pp 25–45
Sneath PHA, Sokal RR (1973) Numerical taxonomy. Freeman, San Francisco
Southern EM (1975) Detection of specific sequences among DNA fragments separated by gel electrophoresis. J Mol Biol 98:503–517
Tanaka M, Kawahara T, Sano J (1978) The evolution of wild tetraploid wheats. In:Ramanujam S (ed) Proc 5th Int Wheat Genet Symp New Delhi 1:73–80
Tsunewaki K (1989) Plasmon diversity in Triticum and Aegilops, and its implication in wheat evolution. Genome 31:143–154
Wolfe KH, Li WH, Sharp PM (1987) Rates of nucleotide substitution vary greatly among plant mitochondrial, chloroplast, and nuclear DNAs. Proc Natl Acad Sci USA 84:9054–9058
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Communicated by G. Wenzel
Contribution from the Laboratory of Genetics, Faculty of Agriculture, Kyoto University, Japan, No. 535
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Mori, N., Liu, Y.G. & Tsunewaki, K. Wheat phylogeny determined by RFLP analysis of nuclear DNA. 2. Wild tetraploid wheats. Theoret. Appl. Genetics 90, 129–134 (1995). https://doi.org/10.1007/BF00221006
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DOI: https://doi.org/10.1007/BF00221006