Molecular cytogenetics reveals an uncommon structural and numerical chromosomal heteromorphism in Zephyranthes brachyandra (Amaryllidaceae)
Background and aims: Zephyranthes brachyandra belongs to a tribe of ornamental Amaryllidaceae native of South America, whose genera circumscription and phylogenetic relationships are still unclear. Cytologically, Z. brachyandra is a tetraploid whose chromosomes are of similar size and morphology, hi...
Guardado en:
| Autores principales: | , , , , |
|---|---|
| Formato: | Artículo revista |
| Lenguaje: | Inglés |
| Publicado: |
Sociedad Argentina de Botánica
2022
|
| Materias: | |
| Acceso en línea: | https://revistas.unc.edu.ar/index.php/BSAB/article/view/34304 |
| Aporte de: |
| Sumario: | Background and aims: Zephyranthes brachyandra belongs to a tribe of ornamental Amaryllidaceae native of South America, whose genera circumscription and phylogenetic relationships are still unclear. Cytologically, Z. brachyandra is a tetraploid whose chromosomes are of similar size and morphology, hindering the identification of its 2n = 24 chromosomes. The aim of this study was to investigate the stability of the many CMA+ and DAPI+ bands and the occurrence of B chromosomes by a cytomolecular approach.
M&M: For this investigation we conducted a cytomolecular analysis with CMA/DAPI staining and fluorescence in situ hybridization with 5S and 35S rDNA probes, and the TTTAGGG telomeric probe.
Results: In the present work, a cytomolecular analysis of Z. brachyandra, revealed a large and variable number of CMA+ and DAPI+ heterochromatic bands and 5S and 35S rDNA sites, and a regular distribution of the TTTAGGG telomeric sequences. In addition, one individual was monotrisomic with 2n = 24, and another one had a B chromosome. Both numerical and structural chromosome alterations were clearly characterized by CMA/DAPI bands and rDNA sites.
Conclusions: Comparing the present data with the cytological data for other species of Zephyranthes, it becomes clear that a cytomolecular approach is fundamental to the understanding of the chromosome variation and cytotaxonomy of the group. |
|---|