Comparative analysis of the three Caucasian oak taxa in Georgia (South Caucasus) based on leaf macromorphological variation

Abstract

Comprative analysis of three oak taxa (Q. petraea subsp. iberica, Quercus robur subsp. imeretina, and Q. robur subsp. pedunculiflora) based on the leaf morphological and morphometric analysis have been done. Fifteen statistically significant variables out of the original 24 leaf characters were identified by PCA. The ANOVA F-statistics together with Tukey’s post hoc range test and PCA analysis allowed the identification of some leaf traits with ability to partly differentiate all three studied taxa from each other. Particularly, the leaf traits related to leaf petiole size and number of lobes and intercalary veins are much higher in Q. petraea subsp. iberica individuals compared to Q. robur subsp. imeretina samples, while in Q. robur subsp. pedunculiflora they are intermediate between these two taxa. Linear regression analysis reveals that statistically significant leaf traits combined in the first and second principal components negatively or positively, but significantly weakly or moderately influenced by ecological factors related to different annual and growth season moisture and temperature conditions.