Abstract
The distribution of highly repetitive DNA sequences on chromosomes of tetraploid and hexaploid cytotypes of Aegilops crassa (Dcr1Xcr and Dcr1XcrDcr2 genomes) was studied using C-banding and in situ hybridization analyses with the pSc119, pAs1 and pTa794 DNA clones. In total, 14 tetraploid and five hexaploid accessions were examined. All chromosomes can be identified by their C-banding and ISH pattern with the pAs1 DNA clone. Only a few pSc119 hybridization sites were observed in the telomeric regions of several chromosomes. We found a high level of C-banding polymorphism and only minor variations in labeling patterns. The position of C-bands generally coincided with the location of the pAs1 sequence. Three 5S rDNA loci were detected in tetraploid Ae. crassa, whereas five pTa794 ISH sites were observed in 6x Ae. crassa. All the hexaploid accessions differed from the tetraploids by a reciprocal non-centromeric translocation involving chromosomes A and N. Three additional translocations were detected in the accessions analyzed. The Dcr1 genome of 4x Ae. crassa is highly modified compared with the D genome of the progenitor species Ae. tauschii. Because of the large amount of chromosomal rearrangements, the origin of the Xcr genome remains unknown. The second Dcr2 genome of 6x Ae. crassa is different from the Dcr1 genome but is similar to the D-genome chromosomes of Ae. tauschii, indicating that no additional large rearrangements occurred at the hexaploid level.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Badaev NS, Badaeva ED, Bolsheva NL, Maximov NG, Zelenin AV (1985) Cytogenetic analysis of forms produced by crossing hexaploid triticale with common wheat. Theor Appl Genet 70: 536–541.
Badaeva ED, Friebe B, Gill BS (1996a) Genome differentiation in Aegilops. 1. Distribution of highly repetitive DNA sequences on chromosomes of diploid species. Genome 39: 293–306.
Badaeva ED, Friebe B, Gill BS (1996b) Genome differentiation in Aegilops. 1. Physical mapping of 5S and 18S-26S ribosomal RNA gene families in diploid species. Genome 39: 1150–1158.
Bedbrook RJ, Jones J, O'Dell M, Thompson RJ, Flavell RB (1980) A molecular description of telomeric heterochromatin in Secale species. Cell 19: 545–560.
Chapman V, Miller TE (1978) The relationship of the D genomes of hexaploid Ae. crassa, Ae. vavilovii and hexaploid wheat. Wheat Inf Serv 47: 17–20.
Chennaveeraiah MS (1960) Karyomorphologic and cytotaxonomic studies in Aegilops. Acta Hort Gotob 23: 349–360.
Cermeño MC, Orellana J, Santos JL, Lacadena JR (1984) Nucleolar activity and competition (amphiplasty) in the genus Aegilops. Heredity 52: 603–611.
Dubcovsky J, Dvorak J (1995) Genome identification of the Triticum crassum complex (Poaceae) with the restriction patterns of repeated nucleotide sequences. Am J Bot 82: 131–140.
Dvorak J (1998) Genome analysis in the Triticum-Aegilops alliance. In: Slinkard AE, eds. Proceedings 9th International Wheat Genet Symp Saskatoon, Canada, 2-7 August 1998. University Extension Press: University of Saskatchewan, Canada, pp 8–11.
Dvorak J, Dubcovsky J (1996) Genome analysis of polyploid species employing variation in repeated nucleotide sequences. In: Jauhar PP, ed. Methods of Genome Analysis in Plants. New York: CRC Press Boca Raton, pp 133–145.
Eig A (1929) Monographisch-kritische Übersicht der Gattung Aegilops. Feddes Rep 55: 1–228.
Friebe B, Mukai Y, Gill BS (1992) C-banding polymorphisms in several accessions of Triticum tauschii (Aegilops squarrosa). Genome 35: 192–199.
Gerlach WL, Dyer TA (1980) Sequence organization of the repeated units in the nucleus of wheat which contains 5S-rRNA genes. Nucleic Acids Res 8: 4851–4865.
Gill BS, Friebe B, Endo TR (1991) Standard karyotype and nomenclature system for description of chromosome bands and structural aberration in wheat (Triticum aestivum). Genome 34: 830–839.
Kihara H (1940) Verwandschaft der Aegilops-Arten im Lichte der Genomanalyse. Der Züchter 12: 49–62.
Kihara H (1957) Completion of genome-analysis of three 6x species of Aegilops. Seiken Ziho 8: 3.
Kihara H (1963) Interspecific relationships in Triticum and Aegilops. Zeiken Ziho 15: 1–12.
Kihara H, Tanaka M (1970) Addendum to the classification of the genus Aegilops by means of genome analysis. Wheat Inf Serv 30: 1.
Kihara H, Yamashita K, Tanaka M (1959) Genomes of 6x species of Aegilops. Wheat Inf Serv 8: 3–5.
Kimber G (1995) Genomic analysis and the derivation of evolutionary relationships in the wheat group-a summary. In: Raupp WJ, Gill BS, eds. Proceedings US-Japan Symposium, Classical and Molecular Cytogenetic Analysis. 21-23 March 1994, Manhattan, Kansas, Kansas, Agricultural Experimental Station Report 95-352D, pp 2–10.
Kimber G, Feldman M (1987) Wild Wheat, an Introduction. College of Agriculture University Missouri: Columbia.
Kimber G, Zhao YH (1983) The D genome of the Triticeae. Can J Genet Cytol 25: 581–589.
Lilienfeld FA, Kihara H (1951) Genome-analysis in Triticum and Aegilops. X. Concluding Review. Cytologia 16: 101–123.
Mukai Y, Endo TR, Gill BS (1990) Physical mapping of the 5S rRNA multigene family in common wheat. J Hered 81: 290–295.
Mukai Y, Endo TR, Gill BS (1991) Physical mapping of the 18S-26S rRNA multigene family in common wheat: identification of a new locus. Chromosoma 100: 71–78.
Mukai Y, Nakahara Y, Yamamoto M (1993) Simultaneous discrimination of the three genomes in hexaploid wheat by multicolor fluorescence in situ hybridization using total genomic and highly repeated DNA probes. Genome 36: 489–494.
Nakai Y (1982) D genome donors for Aegilops crassa (DDMM, DDDDMM) and Ae. vavilovii (DDMMSS) deduce from esterase analysis by isoelectric focusing. Jpn J Genet 57: 349–360.
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.
Rayburn AL, Gill BS (1986) Isolation of a D-genome specific repeated DNA sequence from Aegilops squarrosa. Plant Molecular Biol Rep 4: 104–109.
Rayburn AL, Gill BS (1987) Molecular analysis of the D-genome of the Triticeae. Theor Appl Genet 73: 385–388.
Siddique AK, Jones JK (1967) The D genomes of Aegilops crassa Boiss. Bol Genet Inst Fitotec Castelar 4: 29–31.
Teoh SB, Miller TE, Reader SM (1983) Intraspecific variation in C-banded chromosomes of Aegilops comosa and Ae. speltoides. Theor Appl Genet 65: 343–348
Tsunewaki K (1993) Genome-plasmon interactions in wheat. Jpn J Genet 68: 1–34.
Van Slageren MW (1994) Wild Wheats; a Monograph of Aegilops L. and Amblyopyrum (Jaub. & Spach) Eig (Poaceae). Agricultural University Wageningen: the Netherlands; ICARDA: Aleppo, Syria. pp 512.
Witcombe JR (1983) A Guide to the Species of Aegilops L. Their Taxonomy, Morphology and Distribution. Rome: IBPGR Secretariat.
Yamamoto M, Mukai Y (1995) Physical mapping of ribosomal RNA genes in Aegilops and Triticum. In: Li S, Xin ZY, eds. Proceedings 8th International Wheat Genetic Symposium Bejing, China, 20-25 July 1993. pp 807–811.
Zhang HB, Dvorak J (1992) The genome origin and evolution of hexaploid Triticum crassum and Triticum syriacum determined from variation in repeated nucleotide sequences. Genome 35: 806–814.
Zhao YH, Kimber G (1984) New Hybrids with D-genome wheat relatives. Genetics 106: 509–515.
Zhukovsky PM (1928) A critical-systematical Survey of the species of the genus Aegilops L. Bull Appl Bot Genet Plant Breed 18: 417–609.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Badaeva, E.D., Friebe, B., Zoshchuk, S.A. et al. Molecular Cytogenetic Analysis of Tetraploid and Hexaploid Aegilops Crassa. Chromosome Res 6, 629–637 (1998). https://doi.org/10.1023/A:1009257527391
Issue Date:
DOI: https://doi.org/10.1023/A:1009257527391