Structural Features of the Leaf of Ephemeral Species of Representatives of the Brassicaceae Burnett Family in Southwestern Kyzylkum (Uzbekistan)

Abstract

The results of a study conducted by light microscopy of the anatomical structur e of the leaf in ephemeral species from the family Brassicaceae growing under the conditions of Kyzylkum (Uzbekistan) are presented. The following diagnostic, structural adaptive features were revealed: a leaf lamellar, dentate ( Diptychocarpus strictus ), in Leptaleum filifolium —valky. It is pubescent with various types of trichomes: stellate, dendroid ( Meniocus linifolius ), equilateral ( Streptoloma desertorum ) and unequal ( Strigosella , Leptaleum filifolium species), unicellular hooked ( Leptaleum filifolium ). Epidermal cells flattened with wavy or winding walls. The stomata are numerous, not submerged, anomocytic, hemiparacytic, anisocytic types are noted. In all species, the isolate-palisade type of leaf mesophyll predominates. Vascular bundles of all species are sclerified. The main protective features of the leaf of species of the family Brassicaceae are pubescence and sclerification of vascular bundles. We consider the mesomorphic and xeromorphic lines of development ancient and independent. Identified and described signs that can be used in taxonomy and ecology.