Structural Features of Vegetative Organs Spiraea hypericifolia L., Growing in Uzbekistan

The results of a study conducted by light microscopy 
methods of the anatomical structure of the vegetative organs of Spiraea hypericifolia growing in natural 
habitat in the Bakhmal district in the south of the Jizzakh region of 
Uzbekistan are presented and the following diagnostic features are identified: in 
the leaf—isolateral-palisade type of mesophyll leaf; 
thick-walled outer walls of the epidermis; amphystomatic leaves; not submerged 
stomata; chlorophyll-bearing palisade and spongy parenchyma; open collateral 
type of vascular bundles and sclerified, due to collenchymal cells; in the 
stem and root—the beam type 
of structure and more lignified; the stem and root are divided into three 
topographic zones: the periderm (cork), the secondary cortex and the central 
cylinder; the periderm is represented by a cork and its cells are dark brown, 
thick-walled, tightly closed; groups of bast fibers are formed under the cow 
parenchyma; extensive librimiform; core and radial rays elongated and short; 
the phloem is extensive, located between the cortex parenchyma and libriform; 
the narrow core is represented by large and small, round-oval, thin-walled parenchymal 
cells and they contain hydrocytic cells. Diagnostic signs revealed by us 
reflect more xeromorphic of this species. All traits were compared, and we 
concluded that the anatomical traits of the leaf, stem, and root may be useful 
in providing diagnostic traits for distinguishing the taxa studied.

In addition, many species of the genus Spiraea are honey plants and sources of medicinal raw materials. Ascorbic acid, carotene, alkaloids, flavonoids, saponins, tannins were found in various parts of these plants. Spiraea can also be used as soil-strengthening plants [11]- [18]. Many species bloom abundantly and for a long time, are unpretentious and breed easily. They are diverse in height, color of flowers, the form of inflorescences and timing of flowering. Among the spires, you can choose the type and variety for every taste and for a particular planting site, they are considered the best of the bushes for landscaping [19]. Sokolova, A. V. [20] provides a comparative analysis of the structure of the stem and leaf of two closely related species of the Spiraea L. section of the genus Spiraea L., growing in the Amur Region. For the first time the most important diagnostic features that can be used for interspecific diagnostics are identified. It was established that the stems of the species of the Spiraea section can be diagnosed only by the structure of the core, as well as a number of quantitative characters. The leaves of the studied species are well diagnosed by the thickness of the leaf blade in the region of the middle vein and in places remote from the veins, the thickness of the columnar mesophyll, the presence or absence of trichomes.
The anatomical structure of the vegetative organs of Spiraea hypericifolia has not been studied in Uzbekistan.
The aim of our study is to study the anatomical structure of the leaf, stem and root of Spiraea hypericifolia in order to determine the diagnostic signs and loca-

Materials and Methods
The objects of study are the perennial shrub S. hypericifolia of the genus Spiraea Simultaneously with the morphological description, the vegetative organs (leaf, stem and root) were fixed in 70˚ ethanol for anatomical study. A manual method was used to prepare slices of the vegetative organs. Cross sections of the leaf, stem and root were prepared manually using a safety razor. Cross sections of the leaf are made through the middle and the stem and root through the base.
Sections were stained with methylene blue and safranin, followed by gluing in glycerol-gelatin [21]. Descriptions of the main tissues and cells are given according to C. Esau [22], N. S. Kiseleva [23], the epidermis-according to S.F.

Results and Discussion
The leaves of Spiraea hypericifolia are naked or young in their hair, shortly pubescent, oval, oblong-elliptical or lanceolate, with a blunt or sharp tip.
Our studies have shown that the presence or absence of trichomes can serve as an informative sign. In S. hypericifolia trichomes are simple, opaque, awl-pointed, very rarely located along large veins ( Figure 2). The length of the  An assimilation tissue consisting of palisade and spongy cells is located between the adaxial and abaxial epidermis. The palisade parenchyma is chlorophyll-bearing, large and elongated, which consists of 2 -3 rows of cells and is located between the adaxial and abaxial leaf epidermis. The spongy chlorophyll-bearing parenchyma consists of 3 -4 rows and is located between the palisade parenchyma. The spongy parenchyma is round, small-cell with small cavities.
Between palisade and spongy cells are lateral vascular bundles. The main vascular bundles protrude on the abaxial side and are located in the central part of the leaf mesophyll. Conducting bundles are sclerified due to the presence of mechanical tissues (collenchyma) in them (Figure 2  apical and lateral meristems. Therefore, the trunk and side branches of these plants are significantly thickened. They are powerful, highly lignified, with the early development of secondary integumentary tissue (Figure 3). The anatomical structure of the stem is divided into three topographic zones: the periderm (cork), the secondary cortex, and the central cylinder ( Figure 3).
The integumentary tissue-the cork consists of several rows of radially located cells with thick cork-covered membranes. The integumentary tissue is represented by a cork. Its cells are dark brown in color, thick-walled, densely closed. Outwardly, upon division by tangential septa, the cells of the phellogen Primary conductive tissues are preserved in the stem, and then the secondary ones immediately form a continuous cylinder, which in the cross section looks like an almost continuous ring. With age, the emerging cambium changes the anatomical structure of the stem. It annually produces secondary xylem (wood).
Towards the xylem, the cambium works more vigorously, pushing the primary xylem to the core.
Continuous and rhythmic activity of cambium causes the "layering" of wood.
In it, the boundaries between annual growths (annual rings) are clearly distinguishable. This is due to differences in the composition and structure of histological elements formed from cambium at different times of the year. By the number of tree rings, you can determine the age of the plant. The secondary xylem, which occupies a large part of the section, is easy to determine, since its cells are stained red-brown ( Figure 3).
It is represented by tracheid's located in radial rows and multi-row, elongated and short core rays. The core is not wide, it is represented by large and small round-oval, thin-walled parenchymal cells and they contain hydrocytic cells ( Figure 3). The root is the axial organ of a plant that has radial symmetry, has unlimited long growth, has root hairs and a cap and does not form any other organs on itself. The main functions of the root are the absorption of water and minerals dissolved in it from the soil, the attachment of the plant organism to the substrate and the synthesis of organic substances (amino acids, nucleotides, hormones, enzymes and alkaloids). In addition, he performs other functions: the supply of nutrients, respiration, vegetative propagation, communication with soil microorganisms.
The base of the root on the cross section is round, bundled type, more lignified. In the anatomical structure of the roots of the studied species, three main zones can be distinguished: the periderm, the secondary cortex, and the central cylinder. Primary cortex with secondary thickening of the root is usually broken and dies. The integumentary tissue is a cork; at large roots, the cork replaces the cork. Perennial root with a multilayer crust, including large numerous groups of bast fibers and periderm (Figure 4).
The periderm is three-layered, consists of the phellogen, phellem, and phelloderm. Phellogencells are rectangular flattened in the radial direction and passing from the outside to the phellem cells, inside the cell of the phelloderm, the latter is clearly distinguished from the cells of the inner cortex by a larger size and rectangular flattened in the radial direction. Under the periderm is a round-oval secondary cortex parenchyma, which consists of 4 -5 rows and remains throughout (Figure 4).
Under the parenchyma of the cow, groups of bast fibers form. The phloem is extensive, located between the cortex parenchyma and libriform (Figure 4).  lia was studied and diagnostic signs were determined. In the leaf there is an isolated-palisade type of mesophyll leaf; thick-walled outer walls of the epidermis; amphystomatic leaves; unloaded stomata; chlorophyll-bearing palisade and spongy parenchyma; open collateral type of conducting bundles and sclerified, due to collenchymal cells. In the stem and root-the beam type of structure and more lignified; the stem and root are divided into three topographic zones: the periderm (cork), the secondary cortex and the central cylinder; the periderm is represented by a cork and its cells are dark brown, thick-walled, tightly closed; groups of bast fibers are formed under the cow parenchyma; extensive libriform; core and radial rays elongated and short; the phloem is extensive, located between the cortical parenchyma and librimiform; the narrow core is represented by large and small, round-oval, thin-walled parenchymal cells and they contain hydrocytic cells. Diagnostic signs revealed by us reflect more xeromorphic of this species. All characters were compared, and we concluded that the anatomical features of the leaf, stem, and root may be useful in providing diagnostic features to distinguish between studied taxa. Diagnostic signs that we have identified reflect xeromorphic, which shows the widespread prevalence of these species in natural habitat and is also considered the best of shrubs for landscaping in ornamental horticulture and forestry. An anatomical study of the vegetative organs revealed the presence of drugs (ascorbic acid, carotene, alkaloids, flavonoids, saponins), and tannins in the leaf mesophyll, stems of the secondary cortical parenchyma and parenchymal core cells, and their localization was confirmed on the basis of anatomical images. Detected diagnostic signs are used in pharmaceuticals in the process of identifying raw materials.