Features of the micromorphology and anatomy of the leaf Populus tremula L. (sect. Populus) and P. nigra L. (sect. Aigeiros duby, Salicaceae)

The micromorphology and anatomy of the epidermis of the abaxial surface of the leaf of Populus tremula L. (sect. Populus) and P. nigra L. (sect. Aigeiros Duby, Salicaceae) using light and scanning electron microscopes. The main cells of the epidermis of P. nigra according to N.A. Aneli are curvilinear curvilinear; the coefficient of tortuosity of the anticline walls is 14.3±0.3 μm/mm2; the area is from 437.5 to 1300.0 mm2 (average 820.9±39.9); P. tremula - sinuous, close to indented; 23.2± 0.4 μm/mm2; from 187.5 to 612.5 mm2 (average 351.7±12.6). The closing cells of the stomata in both species are lentil-shaped, multidirectional, located on the same level with the main ones. In P. tremula they are rather small (their length is 17.9± 0.4 microns), and in P. nigra they are larger (24.6± 0.4 microns). Stomata density in P. tremula ranged from 333 to 571 pcs/mm2, in P. nigra - from 100 to 183 pcs/ mm2. There is a folded (striate) microrelief near the stomata. In P. nigra, straight or sinuous folds ranging from 5 to 25 pieces diverge in different directions at a distance of 10 to 27 microns. Three types of microrelief were found. At P. tremula a small number of periosteal folds (from 3 to 17 pcs.) diverged perpendicular to the stomatal slit in different directions at a distance of ~ 10-20 microns.