[article]
| Titre : |
Karyological analysis and genome size in Milium (Gramineae) with special reference to polyploidy and chromosomal evolution |
| Type de document : |
texte imprimé |
| Auteurs : |
Simon T. Bennett, Auteur ; Sandra M. Thomas, Auteur |
| Année de publication : |
1991 |
| Article en page(s) : |
pp. 868-878 |
| Langues : |
Anglais (eng) |
| Catégories : |
[Espèces (in biblio)] Milium
[Espèces (in biblio)] Milium effusum
[Espèces (in biblio)] Milium montianum
[Espèces (in biblio)] Milium vernale
|
| Mots-clés : |
analyse des caryotypes dimension génomique polyploïdie évolution chromosomique |
| Résumé : |
"Karyotypes, nuclear DNA amounts, and meiotic behaviour are presented for Milium effusum L. (2n = 28), Milium montianum Parl. (2n = 22), and two cytotypes of Milium vernale Bieb. (2n = 8, 10). The bimodal karyotype of M. montianum (8 large and 14 small chromosomes) is described for the first time. Evidence from C-banding and geographical distribution suggests an ancient interracial allopolyploid origin for M. effusum (2n = 28). Although M. montianum is undoubtedly allopolyploid, its parentage is unconfirmed. A strong resemblance between the M. vernale (2n = 8) karyotype and the eight large chromosomes in M. montianum suggests a common ancestry. It is possible that a diploid form of M. effusum contributed the remaining 14 chromosomes. A selective loss of DNA sequences from the smaller chromosomes during the subsequent reorganization of the allopolyploid genome may have enhanced the bimodality of the karyotype. Geographical distribution and a change in the breeding system support the direction of the change x = 5 to x = 4 in M. vernale. Allopolyploidy appears to have played a central role in the chromosome evolution and speciation of Milium.Key words: Milium (Gramineae), karyotype analysis, genome size, polyploidy, chromosome evolution." (source : auteurs) |
| Type de publication : |
périodique |
| Référence biblio : |
Bennett S., Thomas S., 1991 - Karyological analysis and genome size in Milium (Gramineae) with special reference to polyploidy and chromosomal evolution. Genome, 34 (6) : 868-878. |
| ID PMB : |
69476 |
| DOI : |
10.1139/g91-134 |
| Permalink : |
http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=69476 |
in Genome > vol. 34, n°6 (Année 1991) . - pp. 868-878
[article]
|
Karyological analysis and genome size in Milium (Gramineae) with special reference to polyploidy and chromosomal evolution in Genome, vol. 34, n°6 (Année 1991)