Effects of industrial toxicants on leaf structure Populus tremula L. (Salicaceae)

The changes occurring in the microstructure of the leaf of Populus tremula L. have been studied. in the impact zone of the metallurgical plant. The epidermal reaction is manifested in an increase in the number of stomata and main cells of the epidermis on the abaxial and adaxial sides of the leaf blade, respectively, with a decrease in their linear parameters. The stomatal index value increases in the immediate vicinity of the source of contamination. The thickness of the mesophyll and the total thickness of the leaf blade in the contamination zone decrease, while the thickness of the integumentary tissues increases, and the percentage of intercellular cells in the mesophyll also increases. In the columnar mesophyll, there is an increase in the prosenchymality of cells, both in the first and in the second row of front garden cells. Keywords: PALISADE COEFFICIENT, INTERCELLULAR CELL, MESOPHYLL, STOMATA, STOMATAL INDEX, EPIDERMIS, POPULUS TREMULA L.