Limonium mucronatum: plant communities and cytogenetic characterization of an endemic of the Moroccan Atlantic Coast

Abstract

Limonium mucronatum (L.f.) Chaz. (Plumbaginaceae), a strict endemic of Morocco, has a restricted range in the littoral zone between Rabat and Tan Tan (Draa valley). This coastal region at the junction of Mediterranean, Canary and Saharan influences is of considerable biogeographical interest. However, little information exists on L. mucronatum communities and its relationship with bioclimatology or chromosome polymorphisms, which may have an impact in the context of plant conservation. In this study, we analysed L. mucronatum communities and performed a cytometric and karyological characterization of this rare species. Results showed two plant communities associated with this species related to a latitudinal and bioclimatic gradient along the surveyed region. Our study provided for the first time new data regarding nuclear DNA amount and about the numbers, positions and organization of 45S rDNA loci in L. mucronatum. Remarkably, cytogenetic analyses revealed homogeneous ploidy across all studied populations with all individuals with 2n = 12 chromosomes. The results obtained are discussed in the context of the originality of flora and the threats to L. mucronatum communities, and in the perspective of a conservation strategy for this endemic species.

Keywords:

• Atlantic coast of Morocco
• chromosome
• ecology
• flora
• FISH
• genome size
• plant conservation
• vegetation

Acknowledgements

We acknowledge the Haut Commissariat aux Eaux et Forêts et à la Lutte Contre la Desertification, Morocco, for providing scientific permission (N° 04/2015) for collecting samples. Thanks to Sofia I.R. Conceição (LEAF/ISA) for help in cytogenetic experiments and Er-Riyahi Saber (Département de géographie, Université Moulay Ismail, Meknès) for the preparation of the distribution map of L. mucronatum.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was funded by Portuguese national funds through Fundação para a Ciência e a Tecnologia (www.fct.pt/) project PTDC/AGRPRO/4285/2014, LEAF UI/AGR/04129/2013, grants LEAF-AGR/04129/BPD/2015 and IF/01267/2013 attributed to ADC and SC. The Linnean Society of London through the Percy Sladen Memorial Fund provided a grant to ADC for fieldwork under the project “Taxonomic reassessment of Limonium spp. (Plumbaginaceae) from Morocco Atlantic coast”.