Morphological differentiation supports the genetic pattern of the geographic structure of Juniperus thurifera (Cupressaceae)

Abstract

Juniperus thurifera is an important component of woodland communities of dry sites within the West Mediterranean region and is characterised by a strongly disjunctive geographic range. Two subspecies were recognised, subsp. thurifera in Europe and subsp. africana in Africa. The aim of the study was the comparison of phenetic diversity to the pattern of AFLP geographic differentiation of the species described in the literature. The examination of phenetic diversity was based on the biometrical analysis of 17 populations using 12 morphological characters of cone and seed. The differences among populations were analysed using Student's t test, analysis of discrimination, UPGMA agglomeration and hierarchical analysis of variance. The majority of morphological characters differentiated at a statistically significant level between populations and between J. thurifera subsp. thurifera and subsp. africana. Three groups of populations were detected using multivariate statistical analyses. The first, well separated, is subsp. africana, while the following two concern subsp. thurifera.The morphological differentiation of populations appeared similar to that described on the AFLP. The Gibraltar Straight appeared to be the most important barrier.

Genetic structure of Tetraclinis articulata, an endangered conifer of the western Mediterranean basin

“…These patterns have been found in Quercus suber L. (Magri et al 2007), or Pinus pinaster Aiton (Burban and Petit 2003). However, accepting this hypothesis requires a) that Strait of Gibraltar would have acted as a barrier for gene flow (Terrab et al 2008;Boratynski et al 2013), remaining isolated Spanish and Moroccan populations, b) assuming the existence in historical times, of intermediate populations related to Spanish populations, maybe in the Mediterranean islands (e.g. Sicily, Sardinia...), or in northern Algeria, and c) long term persistence of current populations and stability of genetic variation (perhaps since Tertiary).…”

Diversity and biogeographical patterns of legumes (Leguminosae) indigenous to southern Africa

“…Akhani et al (2013), Divíšek et al (2014) and Li et al (2015). The Euclidean distance was used by Biondi et al (2015) and Abbate et al (2016) and both Ward’s method and Euclidean distance by Boratyński et al (2013) and Sirisena et al (2013) in geographical biodiversity studies. The statistical results of the present study are given in the Supplementary material 1 where five main clusters (termed A–E) were noted with a centroid QDGC.…”

Raznolikost i strukturiranost hrvatskih kontinentalnih i alpsko-dinarskih populacija bijele johe (Alnus incana /L./ Moench subsp. incana); geografska i okolišna izolacija kao uzrok fenotipske divergencije

“…The conducted cluster analysis resulted in a hierarchical tree, where the unweighted pair-group method with arithmetic mean (UPGMA) was used to join the clusters, and the Euclidean distance to define the distance between the studied objects. The K-means method was applied to detect phenotypic structure and define the number of K-groups that best explained the morphological variation of populations (e.g Douaihy et al 2012;Boratyński et al 2013;Sobierajska et al 2016). In addition, the biogeographical structure of the studied populations was further ; maximum leaf blade width (MLW); leaf blade length, measured from the leaf base to the point of maximum leaf width (PMLW); leaf blade width at 50% of leaf blade length (LW1); leaf blade width at 90% of leaf blade length (LW2); angle closed by the main leaf vein and the line defined by the leaf blade base and a point on the leaf margin, at 10% of leaf blade length (LA1); angle closed by the main leaf vein and the line defined by leaf blade base and a point on the leaf margin, at 25% of leaf blade length (LA2); petiole length (PL).…”