Morphological variability of Fraxinus angustifolia Vahl in the north-western Balkans

Abstract

<em>Fraxinus angustifolia </em>Vahl is a species native in the north-western Balkans, where it has a divided range. Most of its range is located in flood-prone riparian sites in the Pannonian plain but the species is also found on humid sites along some rivers in the Submediterranean region. We analysed morphologic variation within and between five populations (14 trees/population) located in the Subpannonian and Submediterranean region of Slovenia. Thirty two characters were assessed on ca. 80 leaves from each tree which were divided depending on exposure to sunlight (sun and shade leaves), and 8 traits on each fruit (ca. 50 fruits/tree). A hierarchically designed experiment using analysis of variance confirmed the significant contribution of all the analysed hierarchical levels of variation to the total variation. The results show that the differences between the trees in a single population are the greatest factor of variability of leaves, followed by differences between populations and differences which are the result of variation in exposure to sunlight. Leaves in shade positions are typically larger than those in sunny positions, and they have broader and shorter-pointed leaflets; in this feature they are very similar to the leaves of <em>F. excelsior</em>. Stepwise discriminant analysis showed that the traits which refer to the leaflet number and length are the best differentiating traits between individual populations. The Submediterranean population Dragonja stands out with the smallest leaves and the population Lijak from the same region is the most similar to Dragonja for most morphological traits. In general, phenotypic differences between the Subpannonian and the Submediterranean populations of <em>F. angustifolia </em>are minor and indistinct. Based on the differences ascertained by the study, we can only confirm the presence of <em>F. angustifolia </em>subsp. <em>oxycarpa </em>(Bieb. ex Willd.) Franco et Rocha Alfonso in this part of its natural range

Morphological variability of leaves of Sorbus domestica L. in Croatia

“…By partitioning the total variance to sources of variability for four of the eight studied morphological characteristics, [25] found a greater inter-population variability in comparison with the intra-population one. Contrary to that, in the studies of leaf variability of widely distributed woody species by methods of classic morphometric analysis, it is common for a greater share in the overall variability to be accounted for by the variability of trees within populations [25,31,33,51]. Although the service tree populations in Croatia demonstrated a high degree of interpopulation variability, the study also found a high variability between trees within populations, which suggested a high gene flow between populations.…”

“…In addition to genetic markers, morphological traits were also used. Although in comparison with molecular markers their significance has recently been on the decrease, morphological traits are still frequently applied [25,[31][32][33]. This is supported by an increasing amount of research combining methods of morphometric and molecular analysis [34][35][36].…”

Phenotypic diversity and plasticity index of Eurycoma apiculata populations in Eastern Sumatra, Indonesia based on leaves morphology

“…A total of 45 traits were measured on the leaves as shown in Figure 2 and Table 2 following Gonzalez-Rodrigues and Oyama (2005), Brus et al (2011), Jarni et al (2011), and Poljak et al (2015) methods. Leaflet measurements were conducted using a digital caliper with 0.01 mm accuracy of measurements.…”

“…The high variation within populations might be in part the expression of phenotypic plasticity and/or instability development due to micro-environmental conditions experienced by each tree, but it might be also the result of genotypes differences among individuals. In the studies of leaf morphometric analysis of widely distributed species, the greater variability is common existed within populations (Brus et al 2011;Jarni et al 2011;Poljak et al 2015). High variability within population of E. apiculata might be caused by high gene flow between individuals.…”

Morphometric variability of narrow-leaved ash samaras at the test-tree level

“…F. angustifolia is a hermaphrodite with variable morphology that enabled the establishment of several taxa based on differences in the samara and leaf morphology (Papi et al, 2011). In addition, hybridization between F. angustifolia and F. excelsior is possible, which has been reported by various groups (Papi et al, 2011) based on the observation of intermediate morphologies (Fernández-Manjarrés et al, 2006;Jarni et al, 2011), the genotyping of natural populations (Jeandroz et al, 1996;Papi et al, 2011;Temunović et al, 2012) and the assessment of the morphological and genetic structure of putative hybrid populations (Fernández-Manjarrés et al, 2006;Gerard et al, 2013). Due to hybridization and description of many subspecies based on high variation in morphology, the taxonomic status of F. angustifolia is most complicated (Wallander, 2008).…”