Morphometric analyses of the leaf variation within Quercus L. Sect. Cerris Loudon in Turkey

Abstract

Oaks are classified heavily based on the leaf morphology. However, identification of specimens without acorns is usually controversial in Cerris section. Although members of Cerris section have a broad distribution area, there are only few taxonomic studies. Therefore, the current study is the first to show the discrimination of species in Cerris section based on leaf characters from Turkey. Discrimination among the members of Cerris section over Turkey (Q. cerris L. var. cerris, Q. ithaburensis Decne. subsp. macrolepis (Kotschy) Hedge and Yalt, Q. brantii Lindley, Q. libani Olivier, and Q. trojana P. B. subsp. trojana.) was aimed and variations within and among the species based on 15 qualitative leaf characters was presented. In this work we have studied the natural variability of these species by analysing leaf materials collected from 44 populations around Turkey. Cluster Analysis (CA) and Principal Component Analysis (PCA) were performed to assess intra-specific differentiation and to compare the distribution of variance in the individual and population level. The results showed that the leaf characters presented a good discrimination of five Cerris taxa in PCA at the population level, but the relationships between Q. ithaburensis subsp. macrolepis and Q. brantii showed complex groups in CA. Among the studied taxa, the highest variation was found within Q. cerris populations. In this work, we obtained discrimination of Cerris section species from Turkey based on leaf characters which is quite useful for those herbarium specimens without acorns and in other systematic observations. Additional key words: cluster analysis, numerical taxonomy, oak, principal component analysis Address:

Oak morphological traits: Between taxa and environmental variability

“…Variation in leaf morphology is mostly implicated by LL, SD, NLC, and LW, followed by IBL, DPVS, W0.1, IBL, and RPL, confirming previous results for similar or different species (Boratynski et al, 2008;Bruschi et al, 2000;Dupouey and Badeau, 1993;Ishida et al, 2003;Jawarneh et al, 2013;Kremer et al, 2002). Furthermore, several traits contributed greatly to variation in other investigations but didn't in this work such as NPL, LBS, WTL, IAS, IAL and An (Boratynski et al, 2008;Gailing-Bares et al, 2012;Kremer et al, 2002;Uslu and Bakis, 2014). Hence, there is no single morphological trait that enables to differentiate among all species, but rather a group of traits for specific taxa in a defined context.…”

Combining molecular and fossil data to infer demographic history of Quercus cerris: insights on European eastern glacial refugia

“…macrolepis , Q. brantii , Q. libani and Q. trojana , currently grow in Asia Minor and cannot be distinguished by fossil wood (Emery‐Barbier & Thiébault, ). Fossil leaves and cupules are the best evidence for the local presence of Q. cerris in an area, although identification of leaf specimens without acorns may be controversial because of reported high variation in leaf morphology (Uslu & Bakiş, ). Going back in time, the attribution of fossil leaves to Q. cerris may be problematic and so it is also often limited to Quercus Section Cerris .…”

Genetic, Morphological, and Environmental Differentiation of an Arid-Adapted Oak with a Disjunct Distribution

“…Additionally, five composite variables derived from the principal measurements based on ratios of leaf length to width (LWR) and lobe depth (LODR) were included: LWR_1 (BLBW/Length), LWR_2 (MLBW/Length), LWR_3 (ALBW/Length), LODR_1 (MLBW-UMLS/MLBW), LODR_2 (MLBW-LMLS/MLBW). While specifically adapted for southwestern oaks, these measurements represent typical landmarks used in morphometric analysis in Quercus [56,57]. Normality of data was tested both across and within populations for individual characters using a Shapiro-Wilk test.…”