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Title: Unfurling an improved method for visualizing mitotic chromosomes in ferns
Abstract PremiseCytotaxonomy employs chromosome visualization to study organismal relationships and evolution. Despite the critical value of cytogenetic data, cytotypes are lacking for many plant groups. Here, we present an improved approach for visualizing mitotic chromosomes in ferns, a key lineage of land plants, using the dividing cells of unfurling croziers (fiddleheads). Methods and ResultsOur modified mitotic chromosome preparation incorporates a brief pectinase–cellulase pretreatment, as well as colchicine fixation and the Feulgen reaction to improve the staining and separation of mitotic chromosomes. To demonstrate this easy and efficient assessment, we determined the sporophytic (2n) chromosome number for three fern species:Cheilanthes mollis (2n = 60), Cheilanthes hypoleuca (2n = 120), and Nephrolepis cordifolia (2n = 82). ConclusionsThe new method presented here improves visualizations of mitotic chromosomes from the dividing nuclei of young fern croziers. Fiddleheads are widely accessible in nature and in living collections worldwide, and this modified approach increases their suitability for fern cytotaxonomic studies.  more » « less
Award ID(s):
2232106 1110767
PAR ID:
10633322
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Wiley Periodicals LLC
Date Published:
Journal Name:
Applications in Plant Sciences
Volume:
12
Issue:
4
ISSN:
2168-0450
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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