ABSTRACT

First studied the anatomy of the leaf Allium suworowii in different ecological conditions: Jizzakh region and the Tashkent Botanical Garden named after academician F.N. Rusanov at the Institute of Botany of the Academy of Sciences of the Republic of Uzbekistan. Identifying diagnostic signs of the leaf and determining a different combination of xeromorphic and mesomorphic features ensure adaptation to habitat conditions. Under the conditions that nature mesomorphic signs predominate, and introduction-xeromorphic signs prevail, this indicates that they are adapted to the conditions of introduction of this species.

Keywords:

Anatomy, Leaf, Allium suworowii, Jizzakh Region, Introduction, Tashkent Botanical Garden, Uzbekistan

1. Introduction

With preservation in the world of biological diversity, protection of plant world and their rational use are one of global problems. In this regard, the development of methods for identifying and preserving ornamental, rare and endangered species of natural flora is one of the pressing issues.

According to W.T. Stearn [1] the genus Allium L., there are 750 - 800 species that are widely distributed in Eurasia and America. A number of more than 20 types of onions are widely used by the local population for food. Irrational and exorbitant fees have led to exhaustion and a sharp reduction in the range of many of them.

In addition to natural habitats, species of the genus Allium were also studied in unregulated conditions of the culture phytocenosis (Tashkent Botanical Garden), where they settled 30 - 40 years ago beyond the limits of previously existing exposures [2] . All studied species are bulbous geophytes with an ephemeroid rhythm of development. In life form, they are classified as bulbous nonparticulating monocentric bows [3] . The material was mainly species of the genus Allium from the subgenus Melanocrommyum, (systematic affiliation is given according to F.O. Khasanov [4] . More than 30 Allium species grow in Uzbekistan, among which there are food, medicine and a large number of decorative representatives [5] - [10] .

A.T. Abdullayeva [11] [12] studied the anatomical structure of the assimilating organs of A. pskemense and A. praemixtum under the conditions of introduction of the Tashkent Botanical Garden and determined the adaptive diagnostic features of the assimilating organs of these species. In this regard, the identification of morphological, structural features of the representatives of the genus Allium in natural conditions and with the introduction, and the rationale for their adaptive traits are of great scientific and practical importance.

2. Materials and Methods

The objects of study are Allium suworowii perennial herbaceous plant species of the genus Allium L. Family Amaryllidaceae. In nature, the species range covers the Western Tien Shan.Species identified by F.O. Khassanov [13] .

The material was collected at the beginning of May 2017 from natural conditions―growth of the Jizzakh region, Malguzar region (Malguzar ridge) and in the conditions of introduction from the exhibition of oniony introduced plants of the laboratory “Introductions of woody and herbaceous plants” of the Tashkent Botanical Garden named after acad. N.F. Rusanov at the Institute of Botany, Academy of Sciences of the Republic of Uzbekistan.

Malguzar Range (Jizzakh region, Malguzar district) it belongs to the Central Asian province. Gypsum desert an area of about 300 thousand km²; height above sea level 500 - 550 m. It is characterized by: small amount of precipitation (average 300 - 340 mm per year), high summer (up to 30˚C - 35˚C) and low winter (up to −13 ° C, rarely to −20 ° C) temperature. The soil is sierozem, loamy, loamy, meadow alluvial, brown, slightly leached [14] .

Tashkent Botanical Garden is located in the north-eastern part of Tashkent in the basin; chirchik in the low adyr belt at an altitude of 450 - 480 m above sea level. The climate is sharply continental. The average annual precipitation during the study was 337 mm, the average annual temperature 13.8˚C. Precipitation falls mainly in the autumn-winter and spring periods; soil cultural-irrigated gray soils or irrigated sierozem [15] .

Studies were conducted in terms of nature and introduction. Simultaneously with the morphological description, the sheet was fixed in 70% ethanol for anatomical study. The leaf epidermis was studied on paradermal and cross sections. The cross sections of the leaf are made through the middle. Descriptions of the main tissues and cells are given according to K. Esau [16] , N.S. Kiseleva [17] , and the epidermis according to S.F. Zakharevich [18] . The measurements were carried out depending on the organ, tissues and cells in a 30 - 90 short repetition with an eyepiece micrometer followed by transfer to microns. Preparations prepared by hand were stained with methylene blue followed by gluing to glycerin-gelatin [19] . Micrographs were taken by computer micro plotting with a Canon A123 digital camera under the Motic B1-220A-3 microscope. Statistical processing of quantitative data was carried out according to generally accepted criteria [20] using a personal computer (MS-Excel program).

3. Results and Discussion

The leaves of Allium suworowii are a variety, 2 - 6 in number, 30 - 40 cm long, 2.5 - 3.5 cm wide, rough on the edge, bluish, much shorter than the arrow. The arrow was a height of the 40 - 100 cm.

The structure of the leafof A. suworowii in nature (Jizzakh region). On the paradermal section, the outlines of the epidermal cells are straight, elongated longitudinally, epidermal cells numerous on the abaxial side (per 1 mm²―75.6 ± 0.83) than on the adaxial side (per 1 mm²―50 ± 0.45). The cells of the adaxial epidermis are larger than the abaxial ones. The leaves are amphiphomatic. The stomata are transverse to the longitudinal axis of the leaf. The stomata form is oval (55.6 ± 0.43 - 30.5 ± 0.27 µm in length and width), numerous on the abaxial side (per 1 mm²―111.6 ± 1.15) than on the adaxial side (per 1 mm²―62.5 ± 0.71). The stomata closing cells on both sides of the leaf are almost the same length. The stoma is slightly submerged (12.5 ± 0.08 µm), of the anomocytic type (Figure 1(а¹), Figure 1(а²)), Table 1).

Mesophyll leaf in a cross section isolateral-palisade type includes, which is represented by palisade, spongy cells, latex and vascular bundles.

The epidermis is represented by one row of cells with a thin-walled cuticle (10.5 ± 0.09 µm). The cells of the epidermis are large (30.3 ± 0.31 µm), oval-shaped. The palisade parenchyma consists of two rows, of elongated shape, 130.5 ± 0.6 μm in length, 50.5 ± 0.47 μm in width.

The spongy parenchyma consists of 12 - 13 rows, large cells with a diameter of 81.25 ± 0.92 μm. Lacteal located on the border of palisade and spongy parenchyma with a diameter of 33.33 ± 0.27 μm. Lacteal not stands out among the spongy tissue. The spongy parenchyma consists of rounded cells with large intercellular spaces, and in the middle of the leaf intercellular spaces coalesce, forming small cavities.

Vascular bundles arranged in two rows, of which the top is represented only small bundles. In the bottom row, large beams alternate with one small beam. Vascular bundles closed, collateral, numerous consisting of phloem and xylem, with 9 - 10 vessels with large and small diameter 58.33 ± 0.61 μm (Figure 2(а¹)-(а⁴), Table 1).

The structure of the leaf A. suworowii in the conditions of introduction (Tashkent Botanical Garden). In the paradermal section, the outlines of the

epidermal cells are straight, strongly elongated longitudinally than nature, the epidermis cells are numerous on the abaxial side (per 1 mm²―90.4 ± 1.12) than on the adaxial (per 1 mm²―64.8 ± 0.74). The cells of the adaxial epidermis are larger than the abaxial ones. The leaves are amphiphomatic. The stomata are transverse to the longitudinal axis of the sheet. The stomata form is oval (50.5 ± 0.37 0 27.5 ± 0.21 µm in length and width), numerous on the abaxial side (per 1 mm²―124.5 ± 1.27) than on the adaxial side (per 1 mm²―74.4 ± 0.85). The stomata closing cells on both sides of the leaf are almost the same length. The stomata are more submerged (23.6 ± 0.21 µm), of the anomocytic type (Figure 1(b¹), Figure 1(b²), Table 1).

Mesophyll leaf in a cross section isolateral-palisade type includes, which is represented by palisade, spongy cells, latex and vascular bundles.

The epidermis is represented by one row of oval-shaped cells. The outer membrane of epidermal cells is cutinized and strongly thickened 18.2 ± 0.14 μm.

The epidermis cells are large (36.4 ± 0.25 μm), the palisade parenchyma consists of one row, 77.27 ± 0.87 μm in length, 40.9 ± 0.44 μm in width.

The spongy parenchyma consists of 10 - 12 rows of large cells with a diameter of 90.23 ± 0.5 μm. Between the palisade and spongy cells is small lacteal with a diameter of 12.5 ± 0.20 μm. Lacteal not stands out among the spongy tissue. The spongy parenchyma consists of rounded cells with large intercellular spaces, and in the middle of the leaf intercellular spaces coalesce, forming small cavities.

Vascular bundles arranged in two rows, of which the top is represented only small bundles. In the bottom row, large beams alternate with one small beam. Vascular bundles closed, collateral, numerous consisting of phloem and xylem, with 6 - 7 vessels with large and small diameter 43.75 ± 0.57 μm (Figure 2(b¹)-(b⁴), Table 1).

Based on the biometric analysis of quantitative indicators of A. suworowii leaf, the following prevailing xeromorphic and mesomorphic features in 2 living conditions characteristic of this species were identified (Figure 3, Table 1).

In the leaf A. suworowii (nature)―small, few epidermal cells with thin-walled outer walls; weakly submerged and few stomata; large, multi-row spongy and palisade parenchyma; large lacteals; large, numerous vessels in conducting bundles are mesomorphic signs, prevailing in the conditions of nature.

In the leaf A. suworowii (introduction)―large, numerous epidermal cells with the most thickened outer walls; the most submerged and numerous stomata; small, unordered spongy and palisade parenchyma; small lacteals; small, few vessels in conducting bundles are xeromorphic signs prevailing in the conditions of introduction.

4. Conclusion

Thus, based on the results obtained for a comparative study of the anatomical structure of the leaf of A. suworowii in two different conditions (nature and introduction), a different combination of xeromorphic and mesomorphic sings determined, which provides adaptation to habitat conditions. In A. suworowii, which grows under natural conditions, mesomorphic sings predominate. In A. suworowii, which grows under the conditions of introduction, xeromorphic signs predominate and indicate adaptation to the place of growth.

Acknowledgements

The current research is done under the project VA-FA-F5-008 “Scientific basis for the preservation of the gene pool of rare endemic species of flora of Uzbekistan ex situ and the biology of their reproduction”.

Conflicts of Interest

The author declares no conflicts of interest regarding the publication of this paper.

Cite this paper

Yusupova, D.M. (2018) Comparative Anatomical Structure of the Leaf of Allium suworowii Regel (Amaryllidaceae) in Different Ecological Conditions. American Journal of Plant Sciences, 9, 2676-2683. https://doi.org/10.4236/ajps.2018.913194

References