Spatial Variability of Small-leaved Linden (Tilia cordata Mill.) Leaf Blade

Abstract

The features of asymmetry and shape of small-leaved linden leaf blades (Tilia cordata Mill.) on the Kola Peninsula (Murmansk region, Kirovsk) and in the middle part of Russia (Moscow region, Orekhovo-Zuevo) were studied. The size of leaf blades in the northern population (Murmansk oblast) was significantly smaller (p <0.0001). Five linear traits had non-directional fluctuating asymmetry (FA). The method of geometric morphometrics showed a higher variability of leaf shape in the northern population compared to the southern one. Leaves differed in shape upon re-collection, and the leaf × side factor interaction showed the presence of FA in both populations (Goodall’s F criterion in the northern population was 31.7; in the southern – 92.3; p <0.0001). A high value of directional asymmetry was noted in the population on the Kola Peninsula (p <0.0001). The asymmetry of the shape did not depend on size of the leaf blades. According to linear features, plastic variability, especially in the northern population, strongly correlated with fluctuation variability (r = 0.81-0.82; p <0.05). The obtained data allows us to conclude that method of geometric morphometrics was more complex in determining the stability of development. FA was higher in the southern population, while directional asymmetry with a weak expropriation of FA was higher in the northern population. High latitude did not affect the decrease in developmental stability in terms of FA, but led to a decrease in the area of leaf blades with directional asymmetry.