Особенности строения устьичного аппарата представителей рода Thymus L.

Abstract

Thymus vulgaris L. and Thymus serpyllum L. are sought-after medicinal plants in many countries of the world for their essential oils, flavonoids and tannins. The species of this genus are extremely polymorphic, both in their morphological and anatomical structure and in their biochemical composition. Stomata play an important role in growth and yield formation. The study of the stomatal apparatus and its features is a relevant research topic for agricultural crops.Eight specimens of Th. vulgaris and three specimens of Th. serpyllum from different geographical origins were used for the work. Standard methods of preparation of preparations were used in the study. The results show that both species are characterized by the presence of stomata on both sides of the leaf. In the epidermis of both species analyzed, the diacytic type of the stomatal apparatus predominates, but occasionally the anomocytic type is also found. The size of the stomata for each cultivar was almost constant regardless of the weather conditions of the year, which probably indicates the genetic determinism of the size of the stomata and allows this indicator to be considered as a diagnostic sign in the pharmacognostic analysis of raw materials. The number of stomata on the upper side of the leaf was relatively low (16 to 129 pcs/mm2), while on the lower side of the leaf it ranged from 97 to 701 pcs/mm2 (in Th serpyllum VILAR and Th. vulgaris cv. ‘Colchis’, respectively), but mostly fell within the range of 300 to 400 pcs/mm2.