Open AccessMolecular cytogenetics reveals an uncommon structural and numerical chromosomal heteromorphism in Zephyranthes brachyandra (Amaryllidaceae)
Author(s) -
Thiago Nascimento,
Raquel S. Gonçalves,
Mariana Báez,
Guillermo Seijo,
Marcelo Guerra
Publication year - 2022
Publication title -
boletín de la sociedad argentina de botánica
Language(s) - English
Resource type - Journals
eISSN - 1850-2075
pISSN - 0373-580X
DOI - 10.31055/1851.2372.v57.n1.34304
Subject(s) - biology , amaryllidaceae , karyotype , dapi , chromosome , botany , molecular cytogenetics , heterochromatin , cytogenetics , cytotaxonomy , genetics , staining , gene
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.