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.

摘要

柠檬补血脂（Lf）Chaz。（Plumbaginaceae）是摩洛哥的特有种，在拉巴特（Rabat）和丹坦（Tra Tan）（德拉谷）之间的沿海地带范围有限。在地中海，加那利和撒哈拉的影响交界处的这个沿海地区具有相当大的生物地理意义。但是，关于粘液乳杆菌群落及其与生物气候学或染色体多态性的关系的信息很少，这可能对植物保护产生影响。在这项研究中，我们分析了粘液乳杆菌并对该稀有物种进行了细胞计数和核细胞学鉴定。结果显示，与该物种有关的两个植物群落与沿调查区域的纬度和生物气候梯度有关。我们提供了有关核DNA量第一次新的数据和有关的45S rDNA的位点的数量，位置和组织研究L. mucronatum。值得注意的是，细胞遗传学分析显示，在所有研究人群中，所有个体均具有2 n  = 12染色体的均一倍性。在植物的独创性和对穆克劳森氏菌群落的威胁的背景下，并从该特有物种的保护策略的角度讨论了获得的结果。