Volume 9, Number 3, p.p. 107–111
The anatomical structure of leaves and the contents of anthocyanins and phenols in herbaceous plants from different altitudes of the Minor Caucasus
Eva Chkhubianishvili, Nani Kacharava, Gulnara Badridze, Shota Chanishvili and Tamar Kurdadze
Tbilisi Botanical Garden and Institute of Botany, 1 Kojori Road, 0105 Tbilisi, Georgia
The quantitative characteristics of leaf structure and their anthocyanin and phenolic compound contents have been investigated in the medicinal plants Valeriana tiliifolia Troitzky, Hypericum perforatum L., Veratrum lobelianum Bernh and Polygonum aviculare L. growing at different altitudes of the Minor Caucasus (1700 and 2450 m a. s. l., corresponding to the upper limit of trees and the alpine zone, respectively). An increase of leaf thickness of the epidermal layer, palisade and spongiform parenchyma, also the cell area of the palisade was measured in alpine zone plants and compared with the lower timber zone species. Changes in the quantitative indices of leaf structure, like the number of epidermal cells, amount and size of stomata and the stomatal index of the lower epidermis, were not unidirectional. Thickening of the epidermal layer and mesophyll was correlated with the accumulation of anthocyanins. Quantitative changes of total phenols in the leaves of plants growing in the alpine zone were diverse. Relations between the structure and metabolism of the leaves, and the nature of adaptation to high mountain conditions, were established.
Keywords:
altitude, antioxidants, leaf structure