University of Tasmania
Browse

File(s) under permanent embargo

Karyomorphology and DNA quantification in the marine angiosperm Halophila stipulacea (Forsskal) Ascherson from Mediterranean and Red Seas

journal contribution
posted on 2023-05-20, 02:54 authored by Gargiulo, GM, Vilardo, I, Cambrea, G, Gemelli, F, Crosca, A

Cytogenetic studies for systematic and evolutionary purposes are lacking on marine phanerogams. Halophila stipulacea is a tropical seagrass that invaded the Mediterranean from the Red Sea through the Suez Canal. In this study, we report, for the first time, the karyotype features and genome size of H. stipulacea populations from different localities. Also, an attempt to compare our data with those reported in literature on other Halophila species is discussed. To determine the karyological relationships among taxa, we used basic karyotypic features such as chromosome number, size and symmetry, and position of chromosomal landmarks. To estimate karyotype asymmetry, the Coefficient of Variation of Chromosome Length (CVCL) and the Mean Centromeric Asymmetry (MCA) values were calculated. The estimations of DNA amounts were carried out by Image Cytometry (IC) using the interphase-peak method. All the taxa, including those reported in literature, present a uniform and slightly bimodal karyotype, but significant differences are found in nuclear DNA content among species. Each taxa had a karyotype formula 2n = 18 = 10m + 2sm + 6st. Aneuploidy and polyploidy seemed to not be involved in the speciation of this genus. The conserved karyotype in these taxa suggests the presence of mechanisms selecting for constancy, or against changes, in karyotype number and morphology.

History

Publication title

Aquatic Botany

Volume

148

Pagination

1-9

ISSN

0304-3770

Department/School

Institute for Marine and Antarctic Studies

Publisher

Elsevier Science Bv

Place of publication

Po Box 211, Amsterdam, Netherlands, 1000 Ae

Rights statement

Copyright 2018 Elsevier B.V.

Repository Status

  • Restricted

Socio-economic Objectives

Marine biodiversity

Usage metrics

    University Of Tasmania

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC