Mesophyll Structure Research Articles

Linking structure to function: the connection between mesophyll structure and intrinsic water use efficiency.

Climate change-driven drought events are becoming unescapable in an increasing number of areas worldwide. Understanding how plants are able to adapt to these changing environmental conditions is a non-trivial challenge. Physiologically, improving a plant's intrinsic water use efficiency (WUEi ) will be essential for plant survival in dry conditions. Physically, plant adaptation and acclimatisation are constrained by a plant's anatomy. In other words, there is a strong link between anatomical structure and physiological function. Former research predominantly focused on using 2D anatomical measurements to approximate 3D structures based on the assumption of ideal shapes, such as spherical spongy mesophyll cells. As a result of increasing progress in 3D imaging technology, the validity of these assumptions is being assessed, and recent research has indicated that these approximations can contain significant errors. We suggest to invert the workflow and use the less common 3D assessments to provide corrections and functions for the more widely available 2D assessments. By combining these 3D and corrected 2D anatomical assessments with physiological measurements of WUEi , our understanding of how a plant's physical adaptation affects its function will increase and greatly improve our ability to assess plant survival.

Frond and mesophyll traits related to photosynthetic capacity and water‐use efficiency in ferns with different life‐forms ex situ

AbstractLeaf traits are known as indicative of species functional properties in angiosperms. Fern fronds are little studied in this concern, especially ex situ. We studied leaf mesophyll structure, pigments and gas exchange in four fern species grown in a glasshouse—Sphaeropteris cooperi (terrestrial tree fern), Phlebodium aureum (semi‐epiphytic herbaceous), Asplenium australasicum (epiphytic shrubby) and Platycerium bifurcatum (epiphytic herbaceous). Saturated assimilation rate (Asat) decreased and intrinsic water use efficiency (iWUE) increased from a terrestrial tree fern to epiphytic ferns. Asat positively correlated with chloroplast number (Nchl/A) and their surface area per leaf area (Achl/A). iWUE negatively related to Nchl/A and chlorophyll/carotenoid ratio. Most differences between species were found in the mesophyll thickness (MT) and mesophyll cell volume (Vcell) with the smallest values in S. cooperi and the largest ones in P. bifurcatum. We found that photosynthetic limitations in ferns were related to the chloroplast photosynthetic activity rather than to Nchl/A or pigment content which did not differ from most angiosperms. Epiphytic ferns showed larger values of Vcell per cell and per chloroplast compared to angiosperms and tree ferns. We concluded that an increase in MT and Vcell in the studied ferns was not associated with photosynthetic performance, but was related to volumetric cytoplasm–chloroplast ratio meaningful to light absorption and the water‐storage function of fern fronds.

Leaf drought adaptive response in winter oilseed rape is altered at the onset of senescence: a study combining NMR relaxometry, multi-omics and microscopy.

Climate change is bringing more frequent and intense droughts, reducing overall water availability and adversely affecting crops. There is a need to improve our understanding of the tissular and cellular adaptation mechanisms that are critical for plant water conservation strategies. Here, we have used NMR relaxometry in combination with microscopy and multi-omic analysis to study the effects of progressive soil drought on winter oilseed rape (WOSR, Brassica napus L., cv. Aviso) leaves. This study reveals the structural and metabolic adjustments these leaves operate to maintain cell homeostasis. Our results are original in showing that the adaptive responses are altered in leaves at the onset of senescence, associated with changes in metabolic plasticity and mesophyll structures. Thus, long-term responses in young leaves involving osmotic adjustment were combined with the maintenance of tissue hydration and cell growth, contributing to high survival and recovery capacity. For the first time, short-term responses observed in early senescent-old leaves were associated with early drought-induced dehydration of the spongy layer. However, this dehydration was not followed by osmotic adjustment and did not allow maintenance of leaf tissue turgor. These findings open further studies on the genetic variability of drought responses related to identified short- and long-term structural and metabolic plasticity traits in Brassica species.

Partial root-zone drying irrigation improves intrinsic water-use efficiency and maintains high photosynthesis by uncoupling stomatal and mesophyll conductance in cotton leaves.

Partial root-zone drying irrigation (PRD) can improve water-use efficiency (WUE) without reductions in photosynthesis; however, the mechanism by which this is attained is unclear. To amend that, PRD conditions were simulated by polyethylene glycol 6000 in a root-splitting system and the effects of PRD on cotton growth were studied. Results showed that PRD decreased stomatal conductance (gs) but increased mesophyll conductance (gm). Due to the contrasting effects on gs and gm, net photosynthetic rate (AN) remained unaffected, while the enhanced gm/gs ratio facilitated a larger intrinsic WUE. Further analyses indicated that PRD-induced reduction of gs was related to decreased stomatal size and stomatal pore area in adaxial and abaxial surface which was ascribed to lower pore length and width. PRD-induced variation of gm was ascribed to the reduced liquid-phase resistance, due to increases in chloroplast area facing to intercellular airspaces and the ratio of chloroplast surface area to total mesophyll cell area exposed to intercellular airspaces, as well as to decreases in the distance between cell wall and chloroplast, and between adjacent chloroplasts. The above results demonstrate that PRD, through alterations to stomatal and mesophyll structures, decoupled gs and gm responses, which ultimately increased intrinsic WUE and maintained AN.

A COMPARATIVE PHARMACOGNOSTIC EVALUATION OF THE LEAVES OF TULSI (OCIMUM BASALICUM) AND (OCIMUM SANCTUM)

The pharmacognostic evaluation of Ocimum basilicum (Sweet Basil) and Ocimum sanctum (Holy Basil) involved detailed macroscopic and microscopic analyses of their leaves. Ocimum basilicum leaves typically measure 4-8 cm in length, displaying an elliptic ovate shape, whereas Ocimum sanctum leaves are relatively smaller, measuring about 2-2.5 cm in length and exhibiting an ovate shape. Microscopic examination further distinguished between the two species: O. sanctum displayed a square-shaped epidermis characterized by parenchymatous cells and sclerenchyma patches, whereas O. basilicum showcased a dorsiventral mesophyll structure with stomata and glandular trichomes. These distinctive features contribute significantly to the standardization, authentication, and quality control processes essential for ensuring the efficacy and safety of herbal medicine formulations containing Ocimum basilicum and Ocimum sanctum.

الصفات الظاهرية والدقيقة لـ Citrus reticulata Blanco المزروع في شرق ليبيا

Citrus reticulate Blanco is economically and medically important and cultivated in Al-Marj city (Libya). In this study, the morphological, epidermal and anatomical characteristics of Citrus reticulate were considered in a laboratory experiment through staining of cut sections and microscope visualization with the aim of providing detailed description of characteristics of this plant species. Morphological characteristics of leaves, fruits, and seed are very important in comparing between Citrus species. Epidermal attributes such as a variety of cell shapes, hypostomatic, anamocytic stomata, and the presence of secretory cavities on the upper surface of the epidermis are valuable characteristics in distinguishing Citrus species. Also, the mesophyll structure, the shape of vascular bundle, the presence of druses and the secretory cavities features have taxonomic value in the Citrus genus. Additionally, the petiole features, the presence of trichomes and druses and characteristics of the vascular bundles are important for determining phylogenetic relationships between Citrus species. Key words: Citrus reticulata, morphology, anatomy, secertory cavities and druses, Al- Marj (Libya).

Anatomical Structure of the Calyx Transverse Section of Some Species of the Hedysarum L. Genus (Fabaceae) From Central Asia

This research investigates the anatomical structure of the calyx transverse section of 11 species of the Hedysarumgenus from Central Asia. The analysis revealed that all species exhibit a more or less smooth or slightly convoluted upper surface and a lower surface with varying degrees of tuberculation. Regarding the mesophyll structure of the calyx, the studied species are mainly divided into two groups: in H. pumilum, H. severtzovii, H. micropterum, and H. wrightianum, the mesophyll is differentiated into lower palisade and upper spongy layers, which is considered an adaptive and progressive feature for the calyx; in other species, an undifferentiated mesophyll is observed, regarded as a primitive trait. Furthermore, the formation of large and giant idioblasts is characteristic of all studied species, located on the lower side of the calyx (directly beneath the lower epidermis), along with a 2-4-layered chlorenchyma beneath the upper epidermis, representing adaptive features.

Morphology, Anatomy and Chemical Composition of Salvia fruticosa Mill in Al-Marj (Libya)

Macro, micromorphological and chemical characteristics of Salvia fruticosa Mill, wild growing in Libya were studied. The aim of the present study is to provide new properties for the identification and description of this species. The features of leaf morphology, verticillaster number, bract, calyx, corolla, stamens, trichomes, collenchyma’s rows, vascular bundle and mesophyll structure are important characters to distinguish this species. In the study, we observe morphologically different types of glandular trichomes. The results of leaf architecture studies can provide a more accurate basis for the identification of this species. The essential oil contained cineol (43.93%), β-pinene (11,43%), α-pinene (9.53%), β-myrcene (9.08%), caryophyllene (8.75%), camphor (5.12%) and α-terpineol (4.15%).

Revealing the effects and mechanisms of arbuscular mycorrhizal fungi on manganese uptake and detoxification in Rhus chinensis

Arbuscular mycorrhizal fungi (AMF) can alleviate heavy metal phytotoxicity and promote plant growth, while the underlying mechanisms of AMF symbiosis with host plants under manganese (Mn) stress remain elusive. A pot experiment was carried out to investigate the plant growth, micro-structure, Mn accumulation, subcellular distribution, chemical forms, and physiological and biochemical response of Rhus chinensis inoculated with Funneliformis mosseae (FM) under different Mn treatments.The results showed that compared with plants without FM, FM-associated plants exhibited higher growth status, photosynthetic pigments, and photosynthesis under Mn stress. FM-associated plants were able to maintain greater integrity in mesophyll structure, higher thickness of leaf, upper epidermis, and lower epidermis under Mn treatment, and promote leaf growth. Mn accumulation in leaves (258.67–2230.50 mg kg−1), stems (132.67–1160.00 mg kg−1), and roots (360.92–2446.04 mg kg−1) of the seedlings inoculated with FM was higher than non-inoculated ones. FM-associated plants exhibited higher osmotic regulating substances and antioxidant enzymes’ activities under Mn exposure, suggesting lower Mn toxicity in FM inoculated seedlings, despite the augment in Mn accumulation. After FM inoculation, Mn concentration (151.04–1211.32 mg kg−1) and percentage (64.41–78.55%) enhanced in the cell wall, whilst the transport of Mn to aerial plant organs decreased. Furthermore, FM symbiosis favored the conversion of Mn from high toxic forms (2.17–15.68% in FEthanol, 11.37–24.52% in Fdeionized water) to inactive forms (28.30–38.15% in FNaCl, 18.07–28.59% in FHAc, 4.41–17.99% in FHCl) with low phytotoxicity. Our study offers a theoretical basis for remediation of the FM- R. chinensis symbiotic system in Mn-contaminated environments.

Transcriptome analyses of leaf architecture in Sansevieria support a common genetic toolkit in the parallel evolution of unifacial leaves in monocots.

Planar structures dramatically increase the surface-area-to-volume ratio, which is critically important for multicellular organisms. In this study, we utilize naturally occurring phenotypic variation among three Sansivieria species (Asperagaceae) to investigate leaf margin expression patterns that are associated with mediolateral and adaxial/abaxial development. We identified differentially expressed genes (DEGs) between center and margin leaf tissues in two planar-leaf species Sansevieria subspicata and Sansevieria trifasciata and compared these with expression patterns within the cylindrically leaved Sansevieria cylindrica. Two YABBY family genes, homologs of FILAMENTOUS FLOWER and DROOPING LEAF, are overexpressed in the center leaf tissue in the planar-leaf species and in the tissue of the cylindrical leaves. As mesophyll structure does not indicate adaxial versus abaxial differentiation, increased leaf thickness results in more water-storage tissue and enhances resistance to aridity. This suggests that the cylindrical-leaf in S.cylindrica is analogous to the central leaf tissue in the planar-leaf species. Furthermore, the congruence of the expression patterns of these YABBY genes in Sansevieria with expression patterns found in other unifacial monocot species suggests that patterns of parallel evolution may be the result of similar solutions derived from a limited developmental toolbox.

The structure of the needles mesophyll at species of the Pinaceae family

Comparative study of the structure of the needle mesophyll and the diversity of assimilatory cell forms at 27 species from 7 genera (Abies, Tsuga, Pseudotsuga, Picea, Pinus, Cedrus, Larix) of the Pinaceae family was carried out. The researches were carried out under a light microscope using macerated preparations, as well as on transverse, paradermal and radial sections of the middle part of the needles. Among the cells of complex shape, flat cellular cells located along the needles, flat folded cells, the main projections appearing on the transverse sections, and more complicated folded-cellular, combining lobed outlines in the cross-section and cellular in the longitudinal direction, were distinguished. The genera of Pinaceae under consideration can be divided into two groups according to the structure of the assimilatory tissue of needles by the presence or absence of cells of complex shape, in connection with which the prevailing types of mesophyll for each genus are distinguished and characterized in more detail. It is shown that within the separate genera of the Pinaceae family, the characteristic features are observed in the structure of the needles mesophyll, which may also be partly due to the presence of different variants of cells of complex cellular and folded forms.

Leaf mesophyll structure and tree biomass of birches from different climatic zones in Northern Eurasia

In the context of global climate change, it is becoming increasingly important to study the adaptation of forest-forming species, assess their productivity and predict the transformation of forest ecosystems. Here we present the analysis of leaf mesophyll structure and tree biomass in populations of Betula pendula Roth and Betula pubescens Ehrh. along the global climatic transect representing the latitudinal distribution area of these species in Northern Eurasia. It has been shown that with distance from climatic optimum, biological productivity decreases and a structural rearrangement of leaf mesophyll based on a change in cell size and providing a positive carbon balance occurs. High correlations between photosynthetic cells volumes and stem biomass were found. It was concluded that mesophyll cells sizes underlie the structural adaptation of photosynthesis to climate, that determine birch productivity under changing growth conditions. The sizes of photosynthetic cells can be considered as a good predictors of woody species productivity and transformation of forest ecosystems under global climatic changes.

PH-responsive/sustained release nitrogen fertilizer hydrogel improves yield, nitrogen metabolism, and nitrogen use efficiency of rice under alternative wetting and moderate drying irrigation

Rice is challenged by inefficient nitrogen (N) fertilizer and water inputs. However, pH-responsive N fertilizers (pH-RNFs) could improve rice yield and N use-efficiency under water-saving irrigation. Thus, a pot experiment was conducted without N fertilizer (0 mg N/kg, ZNF), with 175 mg/kg mineral N fertilizer (MNF), and with 175 mg/kg pH-responsive N fertilizer (pH-RNF) by using three water regimes: alternate wetting/critical drying (AWCD, 70–60% saturation, 5 cm flooded), alternate wetting/severe drying (AWSD, 80–70% saturation, 5 cm flooded), and alternate wetting/minor drying (AWMD, 100–90% saturation, 5 cm flooded). Under the same alternate wetting/drying regime, the growth traits, yield, and N utilization of rice were found to be higher in pH-RNF than in MNF. The growth attributes and yield and the N efficient use of rice were greater in the AWMD regime than in the AWCD regime under the same N fertilization. The surface area, diameter, length density, oxidation ability, reductase activity, and peroxidase activity of roots were greater in AWMD × pH-RNF than in AWCD × ZNF, because the former treatment increased the total N contents in the rhizosphere, whereas the latter reduced them. In the photosynthesis process, leaf nitrate reductase (41.7 µg/[g.h]) and leaf glutamine synthetase (1158.1 µmol/[g.h]) were larger in AWMD × pH-RNF than in AWCD × ZNF at 22.7 µg/(g.h) and 501.2 µmol/(g.h), respectively, resulting in the amelioration of oxidative leaf cell damage, as revealed by reduced radical oxidative sequence release and lower malonaldehyde level (7.2 µmol/g). Meanwhile, the optimum N nutrition enhanced the leaf mesophyll structure, cell cycle progression, and the development traits of the stem and panicle under the combination AWMD × pH-RNF. Panicle glutamine synthetase (24.35 µmol/[g.h]) and catalase activity (13.86 µg/min) were larger in AWMD × pH-RNF than in AWCD × ZNF at 14.77 µmol/[g.h] and 7.59 µg/min, respectively. The combination AWMD × pH-RNF resulted in the highest N crop removal efficiency (CREN, 49.5%), N agronomic use efficiency (AUEN, 7.97 g/g), N partial factor productivity (PFPN, 18.66 g/g), and N harvest index (HIN, 67.83%). However, the minimum values of CREN (10.3%), AUEN (1.49 g/g), PFPN (7.59 g/g), and HIN (43.48%) were observed in AWCD × MNF. This study suggests that AWMD × pH-RNF could promote root and shoot morpho-physio-biochemical traits, guaranteeing optimal overall plant growth with high yield and adequate N acquisition, and efficient N utilization for sustainable rice production.

Functional consequences of light intensity on soybean leaf hydraulic conductance: Coordinated variations in leaf venation architecture and mesophyll structure

Leaf hydraulic conductance (Kleaf) is a critical determinant of photosynthesis. Prior research has assessed the influence of light intensity on Kleaf by affecting leaf veins. However, whether the mesophyll structure is associated with leaf hydraulic acclimation to different light intensities remains unclear. We investigated the responses of leaf gas exchange and Kleaf to different growth light intensities and checked for the correlation of Kleaf with leaf structural traits in soybean. Low light significantly reduced Kleaf, but Kleaf and stomatal conductance remain coordinated. Low light decreased the stomatal density to match the balance between in water supply and carbon gain capacity. The decline in Kleaf under low growth light condition was partly due to for the reduction of the water movement through leaf veins because of reduced leaf vein thickness and density and xylem conduit size. In addition, low light reduces the mesophyll cell‐to‐cell connectivity and increased the volume fraction of intercellular air space. As a result, the area available for liquid‐phase flow decreases, and subsequently decreased Kleaf. The present study highlights the coordination role between leaf venation architecture and mesophyll structure influencing Kleaf in response to light intensity.

Structure of Needle Mesophyll in the Genus <i>Larix</i> Species (Pinaceae)

The structure of needle mesophyll and the forms of assimilative cells in the genus Larix species are discussed on the example of L. gmelini var. gmelini, L. decidua, L. kaempferi and L. sibirica. Needle samples were fixed in the Gammalund’s mixture. The study of the mesophyll was carried out on transverse, paradermal and radial sections of the middle part of the needles using a light microscope. To clarify the shape of chlorenchyma cells, macerated preparations were used. It is shown that the needle mesophyll in Larix species mainly consists of large cells of complex shape, which touch their convex parts or ends to form a well-developed system of intercellular spaces, which may comtribute to intense gas exchange. Different variants of flat folded, flat cellular and more complicated folded-cellular assimilative cells are described. The flat folded cells are characterized by a variety of lobed configurations on transverse sections and elongated oval projections on radial sections. The flat cellular cells are found on needle longitudinal sections of and consist of cellular links facing both perpendicular (cellular cells of the first group) and parallel (cellular cells of the second group) to the leaf surface. The folded-cellular cells combine transverse folded contours and longitudinal cellular outlines. In the needle mesophyll of the studied Larix species, weak differentiation into palisade and spongy parenchyma is observed; the cells of the middle part (median cells) are additionally distinguished between them. The palisade tissue is formed mainly by cellular cells of the first group, the spongy tissue by cellular cells of the second group. The median cells are located on both sides of the vascular bundle along a large needle radius; they can be either flat and slightly folded, or folded-cellular. The studied Larix species are similar in th esize of assimilative cells and the structure of the needle mesophyll; the main differences between them are related to the features of cell dissection both in transverse and longitudinal directions.

Morphological , Anatomical and Chemical Studies of Salvia Rosmarinus Spenn. Growing in Al- Marj (Libya)

Salvia rosmarinus Spenn (synonym: Rosmarinus officinalis L.) is economically and medically important and grows naturally in Al-Marj (Libya). Macro, micro morphological and chemical characteristics were studied. Leaf venation, leaf anatomy and chemical compounds of essential oils were carried out according to traditional methods. The objective of the present study is to provide detailed description of the characteristics of this species. Morphological charactersistics of leaves, calyx, corolla, stamens are useful for sectional and specific delimitations in Salvia. The leaf architecture characters of primary, secondary, tertiary and quaternary veins are good diagnostic markers for the identification and classification of species. Anatomical characters such as glandular and non- glandular trichomes , mesophyll structure, presence of hypodermis and structure of vascular bundles have been found to have taxonomic value. Cineol (32.38%) is main component of essential oil, followed by Camphor, β-pinene, borneol, Caryophyllene, α-terpineol and α-pinene. Chemical data in essential oils carried taxonomic value of Salvia species.

Anatomical and morphological structure of the leaf of the genus Malus spp.

The article describes changes in the structure, leaves, (including mesophyll structure, structure of the midrib, distribution of stomata, and the number of vascular bundles) in Malus during the growing season (from June to August) under the influence of prolonged drought. The leaves anatomy and morphology were investigated by methods of light and scanning electron microscopy. The study was carried out on four representatives of the genus Malus: M. niedzwetzkyana Borkh., M. baccata ‘Pendula’, M. domestica ‘Eliza Rathke’, M. domestica ‘Renet Simirenko’. The influence of drought on the size of the mesophyll of the leaf plate and the number of stomata along the stretch from June to August was studied. The cell circumference of the sclerenchyma ranged from μm in 27.33 (M. niedzwetzkyana) to 81.92 μm (in M. domestica ‘Elise Rathke’). The number of stomata varied from 214.0 units in (M. domestica ‘Renet Simirenko’) to 304.0 units in (M. baccata ‘Pendula’), length from 11.6 μm (M. baccata ‘Pendula’) to 28.63 μm (M. domestica ‘Elise Rathke’), width from 9.4 μm (M. domestica ‘Elise Rathke’) up to 21.8 μm (M. domestica ‘Elise Rathke’) μm. The length of the trichomes varied from 409.92 μm (M. domestica ‘Renet Simirenko’) to 745.09 μm (M. niedzwetzkyana). Also, the anocytic stomatal type, the number, different stomata and trichomes, the presence of wax on the cuticle, and the found druses of calcium oxalate in M. baccata ‘Pendula’, can be important for systematic phylogeny. Thanks to these studies, it is possible to suggest physiological adaptability of apple trees to prolonged drought, as well as to identify more resistant phenotypes for the breeding process to develop resistant cultivars.

Potassium availability influences the mesophyll structure to coordinate the conductance of CO2 and H2 O during leaf expansion.

Leaf growth relies on photosynthesis and hydraulics to provide carbohydrates and expansion power; in turn, leaves intercept light and construct organism systems for functioning. Under potassium (K) deficiency stress, leaf area, photosynthesis and hydraulics are all affected by alterations in leaf structure. However, the connection between changes in leaf growth and function caused by the structure under K regulation is unclear. Consequently, the leaf hydraulic conductance (Kleaf ) and photosynthetic rate (A) combined with leaf anatomical characteristics of Brassica napus were continuously observed during leaf growth under different K supply levels. The results showed that Kleaf and A decreased simultaneously after leaf area with the increasing K deficiency stress. K deficiency significantly increased longitudinal mesophyll cell investment, leading to a reduced volume fraction of intercellular air-space (fias ) and decreased leaf expansion rate. Furthermore, reduced fias decreased mesophyll and chloroplast surfaces exposed to intercellular airspace and gas phase H2 O transport, which induced coordinated changes in CO2 mesophyll conductance and hydraulic conductance in extra-xylem pathways. Adequate K supply facilitated higher fias through smaller palisade tissue cell density (loose mesophyll cell arrangement) and smaller spongy tissue cell size, which coordinated CO2 and H2 O conductance and promoted leaf area expansion.

The structural correlations and the physiological functions of stomatal morphology and leaf structures in C3 annual crops

This study suggests that stomatal and leaf structures are highly correlated, and mesophyll cell size is an important anatomical trait determining the coordination between stomatal size and mesophyll porosity. A comprehensive study of the correlations between the structural traits and on their relationships with gas exchange parameters may provide some useful information into leaf development and improvement in efficiencies of photosynthetic CO2 fixation and transpirational water loss. In the present study, nine plant materials from eight crop species were pot grown in a growth chamber. Leaf structural traits, gas exchange, and leaf nitrogen content were measured. We found that stomatal size, mesophyll cell size (MCS), and mesophyll porosity were positively correlated and that the surface areas of mesophyll cells and chloroplasts facing intercellular air spaces were positively correlated with both stomatal density and stomatal area per leaf area (SA). These results suggested that the developments of stomata and mesophyll cells are highly correlated among different crop species. Additionally, MCS was positively correlated with leaf thickness and negatively correlated with leaf density and leaf mass per area, which indicated that MCS might play an important role in leaf structural investments and physiological functions among species. In summary, this study illustrates the correlations between stomatal and mesophyll structures, and it highlights the importance of considering the covariations among leaf traits with the intent of improving photosynthesis and iWUE.

The anatomical properties of Salvia section (Lamiaceae) in central district of Mardin (Turkey) and their taxonomic implications

In this study, 4 Salvia species found in the Salvia section distributed in the Artuklu district of Mardin province were analyzed comparatively in terms of anatomy. Plant specimens of Salvia section were collected from 11 localities. Anatomical studies were performed on specimens preserved in 70% alcohol. Transverse sections taken from the roots, stems, leaves, and petioles of the species were examined under a light microscope for anatomical examination. The anatomy of S. bracteata, S. macrochlamys, S. suffruticosa, S. trichoclada species were examined. The S. suffruticosa species was examined in detail for the first time anatomically. The data obtained as a result of the researches were compared with the previous studies on the Salvia section. In anatomical examinations, it was observed that the root, stem, leaf, and petiole structures of the taxa were similar but shapes and measurements in addition to this the number of tissue layers and pith rows are different. Also anatomically analyses, it has been seen that hairiness formed a difference between some species. As a result of all these discussed data, the anatomical characters such as number of ray rows in root, number of collenchyma layers in stem, mesophyll structures in leaves, shape of midrib and number of vascular bundles in petiole, provide important taxonomic information.