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Summary: Multiple distinct specialized regions shape the architecture of maize leaves. Among them, the fringe‐like and wedge‐shaped auricles alter the angle between the leaf and stalk, which is a key trait in crop plant architecture. As planting density increased, a small leaf angle (LA) was typically selected to promote crop light capture efficiency and yield. In the present study, we characterized two paralogous INDETERMINATE DOMAIN (IDD) genes, ZmIDD14 and ZmIDD15, which contain the Cys2‐His2 zinc finger domain and function redundantly to regulate auricle development and LA in maize. Loss‐of‐function mutants showed decreased LA by reducing adaxial sclerenchyma thickness and increasing the colourless cell layers. In addition, the idd14;idd15 double mutant exhibited asymmetrically smaller auricles, which might cause by a failed maintenance of symmetric expression of the key auricle size controlling gene, LIGULELESS(LG1). The transcripts of ZmIDD14 and ZmIDD15 enriched in the ligular region, where LG1 was highly expressed, and both proteins physically interacted with ZmILI1 to promote LG1 transcription. Notably, the idd14;idd15 enhanced the grain yield of hybrids under high planting densities by shaping the plant architecture with a smaller LA. These findings demonstrate the functions of ZmIDD14 and ZmIDD15 in controlling the abaxial/adaxial development of sclerenchyma in the midrib and polar development along the medial‐lateral axes of auricles and provide an available tool for high‐density and high‐yield breeding in maize. [ABSTRACT FROM AUTHOR]

Multiple abiotic stresses such as drought, salinity, heat, and cold stress prevailing in natural habitats affect plant growth and development. Different species modify their structural and functional traits to combat these abiotic stresses while growing in stressful environments. Cenchrus species, i.e., Cenchrus pennisetiformis, C. setiger, and C. prieurii are widely distributed grasses found growing all over the world. Samples from natural populations were collected from different ecological regions in the Punjab and Khyber Pakhtoonkhwa that were exposed to aridity, salinity, and cold, while one site was designated as normal control. In the present study, structural and functional modifications of three Cenchrus species under abiotic stresses were evaluated. It was expected that each Cenchrus species may evolve different strategies to cope with multiple abiotic stresses. All Cenchrus species responded differently whether growing in normal environment or stressful conditions. The most remarkable feature for survival in C. pennisetiformis under cold stress was increased inflorescence and increased stem and root lignification. C. prieurii showed better tolerance to saline and cold environments. C. setiger showed better development of leaf sheath anatomical traits. The structural and functional modifications in Cenchrus species such as development of mechanical tissues provided structural support, while dermal and parenchymatous tissues increased water storage capacity and minimized water loss. An increase in the concentration of organic osmolytes and ionic content aids turgor pressure maintenance and ionic content crucial for plant growth and development. It was concluded that structural and functional alterations in all Cenchrus species were very specific and critical for survival under different environmental stresses. The ecological fitness of these species relied on maintenance of growth and biomass production, and the development of mechanical, vascular, dermal and parenchyma tissues under stressful environmental conditions. Moreover, accumulation of beneficial ions (K+ and Ca2+) and organic osmolytes were critical in turgor maintenance, hence survival of Cenchrus spp. [ABSTRACT FROM AUTHOR]

Vines have insufficient cells with secondary cell walls to resist bending and stems buckle without external support. Some vine species have furrowed xylem that may have less mechanical support compared with vine species with normal xylem. Analyses were performed to quantify anatomical differences between vine stems with and without furrowed xylem. Seven species with and 13 species without furrowed xylem were analyzed with standard histological procedures. The first analysis was done with tissue samples of two furrowed xylem Aristolochia species that had stem areas from 5 to 30 mm2. Xylem and sclerenchyma areas increased as stem areas increased so that the largest stem samples had the 20–30% xylem and 20% sclerenchyma areas. These percentages were typical for all the furrowed species. The second analysis compared 5 mm2 area terminal stem samples of furrowed and nonfurrowed species. Mean xylem areas of samples with and without furrows were 1.28 and 2.11 mm2, respectively. For these samples, results of a t-test produced no statistically significant differences between these two groups even though xylem comprised 18.7% and 35.0% for stems with and without furrows, respectively. All species with furrowed xylem had peripherally located sclerenchyma layer that formed a continuous ring within 10% of the stem surface, while vine species without furrowed xylem had no sclerenchyma. The sum of xylem and sclerenchyma areas in furrowed species were similar to the area of xylem in non-furrowed species. The data suggest that sclerenchyma cells provide significant resistance to stem bending in vines. [ABSTRACT FROM AUTHOR]

Suaeda vera is a succulent halophyte that colonizes hypersaline soils. Ecotypic variability is extremely high. Plant roots are the first line of defense and respond instantly to soil salinity. In the present study, we collected 21 ecotypes from ecologically different habitats to explore the degree of salt tolerance, which can be proved extremely beneficial. This study was conducted to explore the alterations in root morphology, anatomy, and physiology likely to be associated with salinity tolerance. A mechanistic insight was developed to evaluate interaction of soil properties with root modifications toward enhancing survival and development under hypersaline conditions. Increase in salinity was associated with longer root, and, high root fresh and dry biomass. The highest shoot biomass and water contents were found in populations from highly saline habitat (ECe 36.33 to 55.51 dS m−1). Discrete anatomical variations such as reduced parenchymatous region thickness, increased sclerification in the stelar region, and broad metaxylem vessels were recorded at high salinities. The reduced or disintegrated primary tissues (epidermis, endodermis, and cortex) were found to be the main reason that supported the absorption of nutrient from soil-root and root to shoot. The salinity tolerance mechanism relied on root structural modification. The dominant traits enabling salinity tolerance of this species were much larger and fast-conducting metaxylem vessels that enhanced compartmentalization aboveground plant organs. Extensive sclerification in the stelar region involved in water conservation and mechanical strength of roots hence enabled this species to colonize hot arid and saline conditions. [ABSTRACT FROM AUTHOR]

Context: Allelopathy is recognised as a potential technology to control weeds, and could also be a suitable approach for enhancement of crop yield. Aims: The study was conducted to investigate the allelopathic role of Averrhoa carambola leaf extract on growth, anatomical and physiological features of three wheat lines, namely 3094, 7076 and A2011. Methods: Three dilutions i.e. 0% (control), 15% and 30% of the leaf aqueous extract were applied at 15 day intervals (total five applications) on wheat lines until maturity. Key results: All wheat lines showed differential behaviour to allelochemicals of A. carambola leaf extract. Increased root area was accompanied by a high proportion of storage parenchyma tissues and enlarged vascular bundles in line 3094. Disintegration of root cortical parenchyma and complete transformation of chlorenchyma into sclerenchyma in stem was recorded in all wheat lines, particularly at the highest concentration of leaf extract. Line 7076 showed very different behaviour, as it possessed a proportionally enlarged root cortex, enlarged stem vascular bundles and increased leaf thickness, primarily at the highest concentration of leaf extract. Line A2011 was relatively more sensitive, indicating a significant reduction (P < 0.05) in root and stem area and deformed leaves. Conclusions: A low concentration (15%) of leaf extract promoted growth and development, whereas a higher concentration caused significant reduction in growth and anatomical attributes. Implications: A lower dose of Averrhoa leaf extract promoted growth and development in all wheat lines, and hence can be used as a growth promoter. A higher concentration is important for eradicating unwanted plants. Wheat lines were treated with allelochemicals extracted from A. carambola. A low treatment concentration led to increased root area, accompanied by a high proportion of storage parenchyma tissues, and enlarged vascular bundles. Using a high extract concentration, root cortical parenchyma collapsed while stem chlorenchyma was transformed to sclerenchyma. Line 7076 responded differently, as it possessed an enlarged root cortical proportion, enlarged stem vascular bundles and increased leaf thickness. A low concentration (15%) of leaf extract promoted growth, whereas a higher concentration (30%) caused significant reduction in morpho-anatomical traits. [ABSTRACT FROM AUTHOR]

Cyperus niveus Retz., also known as snow white sedge grows in dry mountainous regions of Himalayas. Eight populations of C. niveus were collected from different locations in the Salt Range (Punjab) and Kaghan Valley (Khyber Pakhtoonkhwa) to evaluate role of plasticity in adaptability potential through modification in anatomical traits. This species developed xeric anatomical modifications in roots at higher elevations. These were thick endodermis, formation of sclerenchymatous cells outside endodermis, numerous metaxylem vessels, and increased area of central vessel in roots. Roots were more developed in the Kaghan (K) population, showing the largest root radius (774.7 µm), sclerenchymatous cell area (1429.1 µm2), cortical thickness (147.1 µm), and endodermal cell area (7701.4 µm). Stomatal density (21.7 per mm2) was also the highest in the K population. Formation of aerenchymatous cavities, numerous large vascular bundles with wide metaxylem vessels, and large phloem tissue in stems were the prominent features in the K population at the highest elevation (2078 m a.s.l.). All C. niveus populations showed sclerification around and outside of the vascular bundles, larger adaxial epidermal cell area as compared to abaxial epidermal cells, hypostomatal leaves, and increased storage parenchyma in leaves. [ABSTRACT FROM AUTHOR]

The recalcitrance of plant cell walls poses significant challenges in pretreatment and enzymatic hydrolysis processes, hindering the conversion of lignocellulosic biomass into fermentable sugars. To elucidate the lignocellulosic recalcitrance characteristics of corn stover, this study investigated the anatomical and pore structure of the enzymatic residues from steam-exploded corn stover. The morphology identification of corn stover clarified that the enzymatic residues primarily consisted of sclerenchyma, accounting for 84.43 %. It was found that the sclerenchyma was characterized by a small cavity diameter (3–25 μm) and thick wall (5–8 μm). The surface area of the enzymatic residues increased significantly, while the median pore size decreased compared with the steam-exploded corn stover. The sclerenchyma is the main recalcitrant structure of enzymatic residues. The thick walls and small pores of sclerenchyma cells in enzymatic residues impeded cellulase's mass transfer and penetration, resulting in low distribution density and reduced accessibility. Based on the above analysis of lignocellulosic recalcitrance characteristics, the research findings offer crucial insights into lignocellulosic biomass pretreatment strategies and provide valuable suggestions for industrialization conversion processes. [Display omitted] • Sclerenchyma is the main recalcitrant structure of enzymatic residues. • Sclerenchyma is characterized by its narrow cell cavity and thick cell walls. • Average pore diameter decreases from 6.49 μm to 4.62 μm during enzymatic hydrolysis. • The small size pores hinder the penetration and distribution of cellulase. [ABSTRACT FROM AUTHOR]

Multiple abiotic stresses such as drought, salinity, heat, and cold stress prevailing in natural habitats affect plant growth and development. Different species modify their structural and functional traits to combat these abiotic stresses while growing in stressful environments. Cenchrus species, i.e., Cenchrus pennisetiformis, C. setiger, and C. prieurii are widely distributed grasses found growing all over the world. Samples from natural populations were collected from different ecological regions in the Punjab and Khyber Pakhtoonkhwa that were exposed to aridity, salinity, and cold, while one site was designated as normal control. In the present study, structural and functional modifications of three Cenchrus species under abiotic stresses were evaluated. It was expected that each Cenchrus species may evolve different strategies to cope with multiple abiotic stresses. All Cenchrus species responded differently whether growing in normal environment or stressful conditions. The most remarkable feature for survival in C. pennisetiformis under cold stress was increased inflorescence and increased stem and root lignification. C. prieurii showed better tolerance to saline and cold environments. C. setiger showed better development of leaf sheath anatomical traits. The structural and functional modifications in Cenchrus species such as development of mechanical tissues provided structural support, while dermal and parenchymatous tissues increased water storage capacity and minimized water loss. An increase in the concentration of organic osmolytes and ionic content aids turgor pressure maintenance and ionic content crucial for plant growth and development. It was concluded that structural and functional alterations in all Cenchrus species were very specific and critical for survival under different environmental stresses. The ecological fitness of these species relied on maintenance of growth and biomass production, and the development of mechanical, vascular, dermal and parenchyma tissues under stressful environmental conditions. Moreover, accumulation of beneficial ions (K+ and Ca2+) and organic osmolytes were critical in turgor maintenance, hence survival of Cenchrus spp.

Salt-accumulator species are of great interest for the phytoremediation of salt-affected soils to reclaim soil salinization, a major constraints causing germination retardation and growth restriction of plants as well as habitat degradation. Higher biomass production at ECe 23–36 dS m−1 indicated that this species grows better in high to moderate salinity that was linked to osmotic adjustment through higher ion accumulation (Na+, Cl‒, and Ca2+) and organic osmolytes (free amino acids and proline). Plants from highly and moderately saline habitats exhibited broader metaxylem vessels, which was associated with eased conduction of solutes leading to better growth. Leaf anatomical characteristics generally increased with increasing salinity except at the highest ECe 55 dS m−1. The increased leaf lamina thickness contributed to succulence because of increased storage parenchymatous spongy tissues (that can store high amounts of water), water contents and it is a reflection of maintaining ion homeostasis and colonizing hyper-saline soil. Reduced stomatal density and area under high salinity are critical to cope with environmental hazards. Under high salinity, compartmentalization of excessive Na+ and Cl− ions and accumulation of compatible osmolytes are directly related to high degree of salinity tolerance, and hence are useful for phyto-amelioration of salinity-impacted lands. Salinity tolerance mechanism in Suaeda vera have been explored extensively, but these mechanisms have not been addressed in the context of soil-plant interaction and functioning connection between structural and functional features with respect to phytoremediation. This work aims to provide mechanistic insight into how different morphological and physio-anatomical mechanisms in differently adapted population of Suaeda vera operate in coordinated manner to maintain ionic homeostasis under high salinity that are useful for phytoremediation. [ABSTRACT FROM AUTHOR]

Arabidopsis Casparian strip membrane domain proteins (CASPs) form a transmembrane scaffold to recruit lignin biosynthetic enzymes for Casparian strip (CS) formation. Rice is a semi-aquatic plant with a more complex root structure than Arabidopsis to adapt its growing conditions, where the different deposition of lignin and suberin is crucial for adaptive responses. Here, we observed the structure of rice primary and small lateral roots (SLRs), particularly the deposition patterns of lignin and suberin in wild type and Oscasp1 mutants. We found that the appearance time and structure of CS in the roots of rice are different from those of Arabidopsis and observed suberin deposition in the sclerenchyma in wild type roots. Rice CASP1 is highly similar to AtCASPs, but its expression is concentrated in SLR tips and can be induced by salt stress especially in the steles. The loss of OsCASP1 function alters the expression of the genes involved in suberin biosynthesis and the deposition of suberin in the endodermis and sclerenchyma and leads to delayed CS formation and uneven lignin deposition in SLRs. These different depositions may alter nutrient uptake, resulting in ion imbalance in plant, withered leaves, fewer tillers, and reduced tolerance to salt stress. Our findings suggest that OsCASP1 could play an important role in nutrient homeostasis and adaptation to the growth environment. [ABSTRACT FROM AUTHOR]

Elucidation of the structural and physiological adaptations developed against environmental determinants is a key to understand acclimation and capability to withstand cold in plants colonizing high altitudes. In the present study, two Sorghum species, S. arundinaceum and S. nitidum, were collected from three different elevations (800, 1800 and 2800 m a.s.l.) in the Neelum Valley, Azad Jammu and Kashmir. Above-ground biomass decreased but root growth increased along the altitude gradient in both species. The accumulation of ionic content in root and shoot was high in S. nitidum and low in S. arundinaceum. In S. nitidum, chlorophyll contents showed a significant increase from low to high altitude, while in S. arundinaceum, chlorophyll content decreased with increase in altitude. Both Sorghum species generally showed reduction in root epidermis thickness while metaxylem and phloem area increased along the altitude gradient. Stem and leaf area showed intensive sclerification and increased cortical cell area in S. nitidum, but sclerification in S. arundinaceum reduced from low to high altitude. Stomatal density and stomatal area were reduced in both Sorghum species from lower elevation to higher elevation. In S. arundinaceum, small angular prickles at the leaf margins were observed. It was concluded that narrow vessels, extensive sclerification and hairiness assisted both grasses to tolerate freezing-induced damage and their survival at extremely cold temperatures. [ABSTRACT FROM AUTHOR]

Resilience of growing in arid and semiarid regions and a high capacity of accumulating sugar-rich biomass with low lignin percentages have placed Agave species as an emerging bioenergy crop. Although transcriptome sequencing of fiber-producing agave species has been explored, molecular bases that control wall cell biogenesis and metabolism in agave species are still poorly understood. Here, through RNAseq data mining, we reconstructed the cellulose biosynthesis pathway and the phenylpropanoid route producing lignin monomers in A. tequilana, and evaluated their expression patterns in silico and experimentally. Most of the orthologs retrieved showed differential expression levels when they were analyzed in different tissues with contrasting cellulose and lignin accumulation. Phylogenetic and structural motif analyses of putative CESA and CAD proteins allowed to identify those potentially involved with secondary cell wall formation. RT-qPCR assays revealed enhanced expression levels of AtqCAD5 and AtqCESA7 in parenchyma cells associated with extraxylary fibers, suggesting a mechanism of formation of sclerenchyma fibers in Agave similar to that reported for xylem cells in model eudicots. Overall, our results provide a framework for understanding molecular bases underlying cell wall biogenesis in Agave species studying mechanisms involving in leaf fiber development in monocots. [ABSTRACT FROM AUTHOR]

Fifteen populations of Calotropis procera (Aiton) W.T. Aiton (milkweed) were collected from ecologically different regions of Punjab to evaluate anatomical traits that contribute to the ecological success of this plant in heterogeneous environmental regimes. Structural features relating to stems and leaves showed phenotypic variation. Xeromorphy was high in the desert population possessing thick cuticle and surface hairiness, enhanced xylem vessels, phloem area and deposition of storage parenchymatous tissues (cortex and pith) in the stem and leaves. The population from salt-affected areas showed increased inner phloem area and pubescence in stems, whereas lamina thickness and xylem vessels were greatly enlarged in leaves. The population from mountainous ranges showed the maximum stem area, outer phloem area, cuticle thickness and epidermal cell area. The population along riverbanks showed some prominent features like enlarged bundles of sclerenchyma fibers, and enhanced midrib thickness, cuticle thickness and inner phloem area. The population from the artificial forest plantation had a prominent layer of collenchyma developed under the epidermis, thick lamina and widened xylem vessels. The population from roadsides possessed thick cuticles and enlarged xylem vessels in leaves; in addition, a great proportion of trichomes/hairiness was found on the stem surface. Leaf succulence was the prominent feature of the population adapted to desert and dry mountains. All of these features possibly contribute to C. procera adaptability in a variety of habitats, i.e., desert and semi-desert, salt-affected areas, dry mountains, river/canal banks, roadside and forest plantations, and others. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effect of the presence of calcium oxalate (CaOx) crystals on the micromechanical properties of sclerenchyma tissue from the pecan nutshell (Carya illinoinensis). The microstructure of the cross-section nutshell was examined using light microscopy (LM) and atomic force microscopy (AFM). Using an instrumented indentation system, indentation tests with maximum loads of 500 mN were made on the biological material where the variables studied were the number of crystals present in the evaluated area and the size of individual crystals. Microscopic analysis revealed that the pecan nutshell consists of sclerenchyma tissue with multiple CaOx crystals randomly distributed throughout the material, exhibiting prismatic shapes and various sizes. The results of the indentation tests showed that the examined areas where there were crystals (1, 2 or up to 3) presented values of hardness and elastic modulus significantly higher (P < 0.05) compared to the sclerenchyma (without crystals). Likewise, there were no significant differences (P > 0.05) between the values of the micromechanical properties of the areas evaluated as a function of the number of crystals. On the other hand, it was observed that the size of the crystals did not show a direct correlation with the mechanical properties evaluated as expected. In conclusion, the biomineralization phenomenon is a successful strategy designed by nature to improve the rigidity of the pecan nutshell, where the CaOx crystals strengthen the structure by increasing the micromechanical properties. • The effect of CaOx crystals on the micromechanical properties of the sclerenchyma from the pecan nutshell were evaluated by indentation tests. • The CaOx crystals increased the hardness (≈20%) and elastic modulus (≈13%) of the sclerenchyma tissue locally. • There were no significant differences between the values of the micromechanical properties evaluated as a function of the number of crystals. • The size of the crystals did not show a direct correlation with the mechanical properties. • CaOx crystals strengthen the structure of the pecan nutshell, demonstrating that they fulfill a mechanical function. [ABSTRACT FROM AUTHOR]

Walnut (Juglans regia) kernels are protected by a tough shell consisting of polylobate sclereids that interlock into a 3D puzzle. The shape transformations from isodiametric to lobed cells is well documented for 2D pavement cells, but not for 3D puzzle sclereids. Here, we study the morphogenesis of these cells by using a combination of different imaging techniques. Serial face-microtomy enabled us to reconstruct tissue growth of whole walnut fruits in 3D, and serial block face-scanning electron microscopy exposed cell shapes and their transformation in 3D during shell tissue development. In combination with Raman and fluorescence microscopy, we revealed multiple loops of cellulosic thickenings in cell walls, acting as stiff restrictions during cell growth and leading to the lobed cell shape. Our findings contribute to a better understanding of the 3D shape transformation of polylobate sclereids and the role of pectin and cellulose within this process. [ABSTRACT FROM AUTHOR]

Summary: The encapsulation of seeds in hard coats and fruit walls (pericarp layers) fulfils protective and dispersal functions in many plant families. In angiosperms, packaging structures possess a remarkable range of different morphologies and functionalities, as illustrated by thermo and hygro‐responsive seed pods and appendages, as well as mechanically strong and water‐impermeable shells. Key to these different functionalities are characteristic structural arrangements and chemical modifications of the underlying sclerenchymatous tissues. Although many ecological aspects of hard seed encapsulation have been well documented, a detailed understanding of the relationship between tissue structure and function only recently started to emerge, especially in the context of environmentally driven fruit opening and seed dispersal (responsive encapsulations) and the outstanding durability of some seed coats and indehiscent fruits (static encapsulations). In this review, we focus on the tissue properties of these two systems, with particular consideration of water interactions, mechanical resistance, and force generation. Common principles, as well as unique adaptations, are discussed in different plant species. Understanding how plants integrate a broad range of functions and properties for seed protection during storage and dispersal plays a central role for seed conservation, population dynamics, and plant‐based material developments. [ABSTRACT FROM AUTHOR]

Resilience of growing in arid and semiarid regions and a high capacity of accumulating sugar-rich biomass with low lignin percentages have placed Agave species as an emerging bioenergy crop. Although transcriptome sequencing of fiber-producing agave species has been explored, molecular bases that control wall cell biogenesis and metabolism in agave species are still poorly understood. Here, through RNAseq data mining, we reconstructed the cellulose biosynthesis pathway and the phenylpropanoid route producing lignin monomers in A. tequilana, and evaluated their expression patterns in silico and experimentally. Most of the orthologs retrieved showed differential expression levels when they were analyzed in different tissues with contrasting cellulose and lignin accumulation. Phylogenetic and structural motif analyses of putative CESA and CAD proteins allowed to identify those potentially involved with secondary cell wall formation. RT-qPCR assays revealed enhanced expression levels of AtqCAD5 and AtqCESA7 in parenchyma cells associated with extraxylary fibers, suggesting a mechanism of formation of sclerenchyma fibers in Agave similar to that reported for xylem cells in model eudicots. Overall, our results provide a framework for understanding molecular bases underlying cell wall biogenesis in Agave species studying mechanisms involving in leaf fiber development in monocots.

Capparis odoratissima is a tree species native to semi‐arid environments of South America where low soil water availability coexists with frequent night‐time fog. A previous study showed that water applied to leaf surfaces enhanced leaf hydration, photosynthesis and growth, but the mechanisms of foliar water uptake are unknown. Here, we combine detailed anatomical evaluations with water and dye uptake experiments in the laboratory, and use immunolocalization of pectin and arabinogalactan protein epitopes to characterize water uptake pathways in leaves. Abaxially, the leaves of C. odoratissima are covered with peltate hairs, while the adaxial surfaces are glabrous. Both surfaces are able to absorb condensed water, but the abaxial surface has higher rates of water uptake. Thousands of idioblasts per cm2, a higher density than stomata, connect the adaxial leaf surface and the abaxial peltate hairs, both of which contain hygroscopic substances such as arabinogalactan proteins and pectins. The highly specialized anatomy of the leaves of C odoratissima fulfils the dual function of minimizing water loss when stomata are closed, while maintaining the ability to absorb liquid water. Cell‐wall related hygroscopic compounds in the peltate hairs and idioblasts create a network of microchannels that maintain leaf hydration and promote water uptake. In Capparis odoratissima, an arid‐zone evergreen tree that exhibits foliar water uptake, numerous idioblasts create a network of hygroscopic canals that transport water from the leaf surface to mesophyll cells. [ABSTRACT FROM AUTHOR]

In Leguminosae, extrafloral nectaries are commonly present and differ in their morphological diversity and also in location in the plant body. The literature refers to this structure as a reliable parameter for the taxonomic delimitation of the family, mainly due to the arrangement of vascular bundles and the distribution of sclerenchyma. After the circumscription of the genus Acacia Mill., the individuals belonging to the line Acacia subg. Aculeiferum were elevated under the name of Senegalia Raf., a group of complex taxonomic delimitation. Based on this assumption, this work anatomically characterizes the extrafloral nectaries of Senegalia angico (Mart.) Seigler & Ebinger, in order to provide morphological patterns that aid in the taxonomy of the group. The botanical material of Senegalia angico was collected, fixed, dehydrated, included and sectioned, to be analyzed under light microscopy and photographed using a photomicroscope or photomicroscope trinocular. Senegalia angico has a short-lived and cupuliform nectary. It presents unisserized epidermis and bicellular tectonic trichomes in the base. Delimiting the secretory tissue and vascular bundles, we can observe the sclerenchymatic tissue, which gives it the described architecture. The central vascular bundles of the petiole, facing the nectary, irrigate directly. The arrangement of the sclerenchyma fibers surrounding the extrafloral nectary and the origin of the vascularization of the nectary gave the Senegalia angico a basal position when compared to the other Acacieae lines, confirming the importance of the anatomical study as a tool for the taxonomy.

The objective evaluates the anatomy of elephant grass under different defoliation frequencies and levels of insertion on the tiller. The experiment was set up as a completely randomized design with a 3 × 5 factorial arrangement consisting of leaf sheath insertion levels (IL) on the tiller and defoliation frequencies (30, 45, 60, 75, and 90 days). Leaf area and number of vascular bundles present in the leaf blade and leaf sheath were influenced by IL and defoliation frequencies (P < 0.05). The abaxial epidermis was thicker at the basal IL for both leaf blade and sheath. Regarding the proportion of leaf blade anatomical tissues, for the xylem area, whose highest percentages (9.21 and 10.10%) were observed at the apical IL at the highest defoliation frequencies (30 and 45 days, respectively). The area occupied by the sclerenchyma increased as the level of maturity advanced, in both the leaf and the leaf sheath. [ABSTRACT FROM AUTHOR]

Premise: Because of their own weight and additional wind forces, plants are exposed to various bending and torsional loads that sometimes require contradictory structural characteristics and mechanical properties. The resulting trade‐off between flexural and torsional rigidity can be quantified and compared using the dimensionless twist‐to‐bend ratio. Methods: The flexural rigidity of the stems of Carex pendula was determined by 2‐point bending tests. Additionally, 4‐point bending tests and torsional tests were carried out on segments of two internodes directly below the inflorescences to measure flexural and torsional rigidity. Anatomical investigations were performed to quantify the cross‐sectional distribution of their tissues. Results: The flexural rigidity of the stems, segments of the apical internode 1, and the more basal internode 2 differed significantly from each other, whereas the bending elastic moduli were not significantly different. The torsional rigidity of segments of internode 2 was a factor of 3.3 higher than that of internode 1, whereas the torsional moduli did not differ significantly. The twist‐to‐bend ratios of segments of internode 1 and 2 reached values between 85 and 403. Light microscopic investigations revealed a triangular stem possessing individual sclerenchyma strands, with internode 2 having significantly more strands than internode 1. Conclusions: In the case of Carex pendula, flexural and torsional rigidity are adapted to the given mechanical constraints by significant changes in morphometric variables (axial and polar second moment of area, number of sclerenchyma strands), whereas the material properties (bending and torsional modulus) do not change markedly along the stem. [ABSTRACT FROM AUTHOR]

SUMMARY: The Elongator complex, which is conserved in eukaryotes, has multiple roles in diverse organisms. In Arabidopsis thaliana, Elongator is shown to be involved in development, hormone action and environmental responses. However, except for Arabidopsis, our knowledge of its function is poor in plants. In this study, we initially carried out a genetic analysis to characterize a rice mutant with narrow and curled leaves, termed curled later1 (cur1). The cur1 mutant displayed a heteroblastic change, whereby the mutant leaf phenotype appeared specifically at a later adult phase of vegetative development. The shoot apical meristem (SAM) was small and the leaf initiation rate was low, suggesting that the activity of the SAM seemed to be partially reduced in cur1. We then revealed that CUR1 encodes a yeast ELP1‐like protein, the largest subunit of Elongator. Furthermore, disruption of OsELP3 encoding the catalytic subunit of Elongator resulted in phenotypes similar to those of cur1, including the timing of the appearance of mutant phenotypes. Thus, Elongator activity seems to be specifically required for leaf development at the late vegetative phase. Transcriptome analysis showed that genes involved in protein quality control were highly upregulated in the cur1 shoot apex at the later vegetative phase, suggesting the restoration of impaired proteins probably produced by partial defects in translational control due to the loss of function of Elongator. The differences in the mutant phenotype and gene expression profile between CUR1 and its Arabidopsis ortholog suggest that Elongator has evolved to play a unique role in rice development. Significance Statement: We revealed that genes encoding the subunit of Elongator complex play an important role in the differentiation of bulliform and sclerenchyma cells in leaf development and in the maintenance of the shoot apical meristem. The mutant leaf phenotypes appeared specifically at the late adult phase of the vegetative development, suggesting a unique role of the Elongator complex in rice. [ABSTRACT FROM AUTHOR]

The current study was carried out to investigate the anatomical characteristics of the petiole of eight species of tribe Mentheae collected from different phytogeographical regions of Pakistan. The transverse section was cut using Shandon Microtome (Finesse 325) to prepare slides. Cluster analysis was carried out to represent the agglomeration schedule of species viewed from the cluster point of view. The distinguishing anatomical characteristics of petioles were noted including petiole shapes, number and shape of vascular bundles, number of vessels, layers of collenchyma, and sclerenchyma. Prunella vulgaris and Salvia plebeia were observed with sclerenchyma cells arranged outside the vascular bundle. The comparative anatomical characteristics of petiole provide valuable information in identifying the tribe Mentheae species. Petiole anatomy plays a significant role in future taxonomic and phylogenetic studies. The aim of the present study was to evaluate the taxonomical importance of the petiole anatomy in the tribe Mentheae. This work will be helpful for the taxonomist and the taxonomic importance of the petiole anatomy in this tribe specifically, and generally will provide baseline to the other studies in family Lamiaceae. [ABSTRACT FROM AUTHOR]

An investigation was carried out to evaluate the impact of the allelopathic effect of Alstonia scholaris leaf extract on morphoanatomical and physiological characteristics of 5 wheat lines. Three extract dilutions were prepared, viz. 0 (control), 15 and 30% of the aqueous extract and sprayed on wheat lines (3094, 5066, M5082, 7076 and A2011) at 15-day intervals until maturity from November 2017 to May 2018. All wheat lines responded differently to an allelochemical extract of A. scholaris. Disintegration of root parenchyma and transformation of stem chlorenchyma to sclerenchyma in stems were noted in Line 3094. Increased sclerification in the root cortex (141.7-212.5 µm) and stem hypodermal region (212.5-354.2 µm) was recorded in Line 5066. Line M5082 showed intensive sclerification in the root cortex and vascular region, and around stem vascular bundles along with a significant decrease in leaf thickness. Line 7076 was the most sensitive genotype showing significant reduction in the stem (1402.8-821.8 µm) and root area (963.5- 791.9 µm) and leaf thickness (1346.2-396.8 µm). Line A2011 responded very differently by increasing proportion of parenchyma and sclerenchyma. A low concentration (15%) of allelochemical extract promoted growth and development and a high concentration (30%) was toxic, causing growth retardation and tissue damage. [ABSTRACT FROM AUTHOR]

Summary: Broad‐spectrum resistance is highly preferred in crop breeding programmes. Previously, we have reported the identification of the broad‐spectrum resistance‐Digu 1 (bsr‐d1) allele from rice Digu. The bsr‐d1 allele prevents activation of Bsr‐d1 expression by Magnaporthe oryzae infection and degradation of H2O2 by peroxidases, leading to resistance to M. oryzae. However, it remains unknown whether defence pathways other than H2O2 burst and peroxidases contribute to the bsr‐d1‐mediated immunity.Blast resistance was determined in rice leaves by spray and punch inoculations. Target genes of OsMYB30 were identified by one‐hybrid assays in yeast and electrophoretic mobility shift assay. Lignin content was measured by phloroglucinol–HCl staining, and acetyl bromide and thioacidolysis methods.Here, we report the involvement of the OsMYB30 gene in bsr‐d1‐mediated blast resistance. Expression of OsMYB30 was induced during M. oryzae infection or when Bsr‐d1 was knocked out or downregulated, as occurs in bsr‐d1 plants upon infection. We further found that OsMYB30 bound to and activated the promoters of 4‐coumarate:coenzyme A ligase genes (Os4CL3 and Os4CL5) resulting in accumulation of lignin subunits G and S. This action led to obvious thickening of sclerenchyma cells near the epidermis, inhibiting M. oryzae penetration at the early stage of infection.Our study revealed novel components required for bsr‐d1‐mediated resistance and penetration‐dependent immunity, and advanced our understanding of broad‐spectrum disease resistance. [ABSTRACT FROM AUTHOR]

The walnut shell is a hard and protective layer that provides an essential barrier between the seed and its environment. The shell is based on only one unit cell type: the polylobate sclerenchyma cell. For a better understanding of the interlocked walnut shell tissue, we investigate the structural and compositional changes during the development of the shell from the soft to the hard state. Structural changes at the macro level are explored by X-ray tomography and on the cell and cell wall level various microscopic techniques are applied. Walnut shell development takes place beneath the outer green husk, which protects and delivers components during the development of the walnut. The cells toward this outer green husk have the thickest and most lignified cell walls. With maturation secondary cell wall thickening takes place and the amount of all cell wall components (cellulose, hemicelluloses and especially lignin) is increased as revealed by FTIR microscopy. Focusing on the cell wall level, Raman imaging showed that lignin is deposited first into the pectin network between the cells and cell corners, at the very beginning of secondary cell wall formation. Furthermore, Raman imaging of fluorescence visualized numerous pits as a network of channels, connecting all the interlocked polylobate walnut shells. In the final mature stage, fluorescence increased throughout the cell wall and a fluorescent layer was detected toward the lumen in the inner part. This accumulation of aromatic components is reminiscent of heartwood formation of trees and is suggested to improve protection properties of the mature walnut shell. Understanding the walnut shell and its development will inspire biomimetic material design and packaging concepts, but is also important for waste valorization, considering that walnuts are the most widespread tree nuts in the world. [ABSTRACT FROM AUTHOR]

In dry lands, small millets such as kodo millet contribute to regional food security to some extent. It is normally harvested using paddy combine harvester due to labour scarcity. However, the current varieties are not amenable for mechanized harvesting as they lodge at grain filling and maturity stages, thus resulting in heavy grain loss in terms of quality and quantity. In this context, we studied the anatomical features of culm and elemental composition in relation to lodging behaviour in kodo millet (Paspalum scrobiculatum L.), which is one of the important yield limiting factors in this crop. The strong culm genotype, Adari had higher culm thickness, thicker mechanical tissue, more lignin deposition and more number of vascular bundles per cross section when compared to the weaker counterpart, Aamo10. However, not all the genotypes with thicker culm were lodging resistant. Sel21 which recorded the highest culm thickness (1283.4 µm) among the genotypes lodged heavily as higher culm thickness in Sel21 was not supported by an increased number of vascular bundles. Interestingly, TNPsc183 which had a moderate culm thickness of 782.82 μm exhibited a low degree of lodging and had more number of vascular bundles per cross section than Sel21. Hence, 'number of vascular bundles per unit area' appears to be an important trait in contributing lodging resistance in kodo millet. SEM-EDX studies for silicon and potassium contents in culm implicated the role of silicon, but not potassium in imparting culm strength in kodo millet. However, more potassium content in parenchymatous cell wall suggests its role in imparting strength to the non-lignified cells of the culm. [ABSTRACT FROM AUTHOR]

Understanding what determine plants ability to survive drought and cold is crucial for predicting how plants may respond to ongoing climate change. Plant survival strategies are usually characterized by morphological and physiological adaptations, while their underlying anatomical settings are largely unknown. Woody angiosperms and herbaceous dicots have repeatedly evolved small water transporting conduits and large storage parenchyma tissues at colder or drier places to cope with freezing‐ and drought‐induced damages. However, whether these adaptations are also valid for graminoids remains unclear. Here we show that stem anatomical variations in grasses, sedges and rushes dominating in western Himalayan grasslands are driven by elevation and soil moisture via control over aboveground plant stature and belowground clonal growth, while phylogenetic constraints have only a weak effect. Phylogenetic comparative analyses controlling for confounding factors showed that the elevation‐related cooling controls the conductive system through reduced vessel diameter and extended assimilatory and storage tissues with more chlorenchyma and less sclerenchyma around vessels. The soil moisture deficit, on the other hand, determines stabilization structures by promoting short‐rhizomatous turf graminoids with hollow stems, thicker epidermis and deep adventitious roots in dry steppes and semi‐deserts. Saline wetlands and moist alpine pastures promote long‐rhizomatous short‐stature plants with lower need for mechanical support (absence of hollow stem) and exposure to high evaporative forcing (thinner epidermis). Observed trends of decreasing vessel sizes and lignification rate with elevation supports the existing knowledge that narrower vessels and extensive parenchyma assist plants to grow in cold environments by avoiding freezing‐induced cavitation. Our results bring novel information on ecological drivers influencing the evolution of anatomical adaptations in high mountain graminoids. Distinct grassland types, covering elevations from 2650 to 6150 m, harbor unrelated species with different evolutionary histories that have converged towards similar anatomical structures. [ABSTRACT FROM AUTHOR]

Leaves' anatomical characteristics are considered to be important diagnostic features for identifying grasses. Cross sections from the middle part of leaf blades have traditionally been used for such purposes. Leaf anatomy has been of key interest for identifying the representatives of the Festuca L. genus because of great morphological similarity between the species. Particular attention is paid to the arrangement of sclerenchyma in the middle part of the leaf blade. The lack of knowledge regarding the spatial distribution of tissues throughout the leaf blades of grasses does not allow one to evaluate the diagnostic significance of data obtained from a single, two-dimensional cross section. The aim of the work is to make 3D models of sclerenchyma from serial sections of leaf blades of two narrow-leaved fescues: Festuca valesiaca Gaud. and Festuca beckeri (Hack.) Trautv. Cross-sectional areas of sclerenchyma increase just above the blade/sheath junction and then gradually decrease up to the tips of the leaf blades in both species. Subepidermal sclerenchyma of the fescues appears as an uneven layer. The layer of F. beckeri is more or less solid, the layer of F. valesiaca is dissected by four long splits. Changes in the shape of sclerenchyma sections along the leaf blades are more pronounced in F. valesiaca than in F. beckeri. Variability of the sclerenchyma arrangements along the leaf blades should be considered when using 2D sections of the leaf for diagnostics of fescues. [ABSTRACT FROM AUTHOR]

The digestibility potential of leaves from forages depends on the amount of nutrition in their tissues, with low lignin deposition in the cell wall, mainly parenchyma and phloem. This research evaluated the leaf structure of different Urochloa genotypes and discussed its potential for evaluating digestibility. The cultivars U. brizantha, U. decumbens, U. ruziziensis and three clones of U. ruziziensis (1, 95 and 97), which are under development in breeding programs, were evaluated. Plants were grown under the recommended culture conditions for the Urochloa species. Plants were cut 60 days after sowing, and leaves were collected at 15 days of regrowth. Leaves were fixed in FAA 70 and further stored in 70% ethanol until being submitted to the usual microtechniques for the preparation of microscopy slides. The area of the tissues from the interveinal and midrib regions was measured using ImageJ software, and their proportions were calculated. In the interveinal region, the proportion of chlorophyll parenchyma was greater for U. decumbens and the Clone 1 genotypes. Urochloa brizantha and clones 95 and 97 showed a higher proportion of the vascular bundle compared to U. ruziziensis, U. decumbens and Clone 1. The proportion of the ground parenchyma in the midrib was greater in U. brizantha, Clone 95 and Clone 97. Thus, it can be concluded that the Clone 1 genotypes (from U. ruziziensis) showed leaf tissues (parenchyma and phloem) with higher digestibility potential; in addition, U. brizantha and U. decumbens showed a high percentage of xylem and sclerenchyma, which reduces their quality as forage. [ABSTRACT FROM AUTHOR]

Herbaceous plants rely on a combination of turgor, ground tissues and geometry for mechanical support of leaves and stems. Unlike most angiosperms however, ferns employ a sub-dermal layer of fibers, known as a hypodermal sterome, for support of their leaves. The sterome is nearly ubiquitous in ferns, but nothing is known about its role in leaf biomechanics. The goal of this research was to characterize sterome attributes in ferns that experience a broad range of mechanical stresses, as imposed by their aquatic, xeric, epiphytic, and terrestrial niches. Members of the Pteridaceae meet this criteria well. The anatomical and functional morphometrics along with published values of tissue moduli were used to model petiole flexural rigidity and susceptibility to buckling in 20 species of the Pteridaceae. Strong allometric relationships were observed between sterome thickness and leaf size, with the sterome contributing over 97% to petiole flexural rigidity. Surprisingly, the small-statured cheilanthoid ferns allocated the highest fraction of their petiole to the sterome, while large leaves exploited aspects of geometry (second moment of area) to achieve bending resistance. This pattern also revealed an economy of function in which increasing sterome thickness was associated with decreasing fiber cell reinforcement, and fiber wall fraction. Lastly, strong petioles were associated with durable leaves, as approximated by specific leaf area. This study reveals meaningful patterns in fern leaf biomechanics that align with species leaf size, sterome attributes and life-history strategy.

Anatomical features of the leaves of Quercus L. species are presented in this study for the first time. Leaves are bifacial and the palisade parenchyma of Q. aegilops and Q. libani is stratified into two layers, of nearly equal width, while that of Q. infectoria and Q.macranthera composed of only one layer. The cortex of both midrib and petiole is well developed with collenchyma starting just beneath the epidermis. The collenchyma of Q. aegilops is extremly thick compared with that of other species. Vascular bundles of the midrib and petiole are completely enclosed by the two pericycle layers of fibers and sclerenchyma. While the number of vascular bundles and sclerenchyma groups cupping them is 3 and 2 for midribs of Q. aegilops and Q. libani respectively, the number turns into 2 vascular elements of different appearance in their petioles. Petiole secondary vascular bundles are well developed and their sclerenchyma groups more lignified in Q. infectoria but less developed and reduced in Q. macranthera. From the results, it is concluded that the leaf blade and petiole anatomical features can provide diagnostic characters for distinguishing Quercus species of Iraq. Results also strongly support placing Q. aegilops and Q. libani in the section Cerris but Q. infectoria is more reliable in the section Mesobalanus.

The anatomy of Carex roots was generally considered to be rather uniform. The aim of this work was to provide an overview of the root anatomy of Carex in a phylogenetic context with an even sampling across the different clades. It was tested, if the observed anatomical characters show a relation to the habitat of the species, i.e. the soil moisture conditions. Further, it was asked if the anatomical data may provide useful characters for the comprehension and circumscription of clades. Root sections of 145 species were studied for 8 characters. Relations of root anatomical characters were inferred by linear regressions of phylogenetic independent contrasts. Phylogenetic ANOVAs were calculated to reveal anatomical characters that may have a relation to growth conditions. The anatomical data were mapped on the phylogeny to infer if they may provide useful characters for systematics. The root anatomy of Carex revealed a considerable diversity. Size differences of the roots were in orders of magnitude; particularly apparent were differences in the development of the aerenchyma and the sclerenchymatic tissues of the cortex. Most measures of the anatomy were positively related, only the sclerenchyma shows no significant correlation to other anatomical characters. The size of the sclerenchyma is significantly related to soil moisture, whereas the size of aerenchyma shows only a weak correlation. The development of the sclerenchyma was revealed to be a possible functional trait, whose development is related to dry soils. Unexpectedly, the size of the aerenchyma shows only a weak relation to soil moisture; considerable aerenchyma may be observed in species of all growth conditions. The development of the sclerenchyma and the arrangement of vessels in the central cylinder of the root may be useful characters for the systematics of Carex. [ABSTRACT FROM AUTHOR]

The morpho‐anatomical structure of the adult photosynthetic organs of the Casuarinaceae is unique in plants. We examine the shoot structure of five species from Allocasuarina ‐ the most derived genus in the family. While the cotyledons of seedlings are similar to those of many other plants the subsequent leaves form a whorl of chlorenchymatic tissue fused to the cortex of the articles of segmented branchlets with only the leaf tips free at the apex of each article. Each leaf in the whorl is called a phyllichnium and consists of a vascular trace below the photosynthetic chlorenchyma with sclerenchyma developed within the mesophyll. The branchlets of Allocasuarina are considered xeromorphic as the stomata of most species are restricted to the sides of the furrows formed by the closely appressed edges of the phyllichnia. The scleromorphic foliage of the ancestral Casuarinaceae may have developed from adaptation to nutrient poor soils but was also preadapted to confer drought resistance. The narrow foliage with abundant sclerenchyma, restricted stomatal area and minimal distance from the atmosphere to xylem tissues ensured that the genus could become competitively successful on impoverished soils and be a distinctive component of arid and even mesic woodlands and forests in Australia. [ABSTRACT FROM AUTHOR]

Herbaceous plants rely on a combination of turgor, ground tissues and geometry for mechanical support of leaves and stems. Unlike most angiosperms however, ferns employ a sub-dermal layer of fibers, known as a hypodermal sterome, for support of their leaves. The sterome is nearly ubiquitous in ferns, but nothing is known about its role in leaf biomechanics. The goal of this research was to characterize sterome attributes in ferns that experience a broad range of mechanical stresses, as imposed by their aquatic, xeric, epiphytic, and terrestrial niches. Members of the Pteridaceae meet this criteria well. The anatomical and functional morphometrics along with published values of tissue moduli were used to model petiole flexural rigidity and susceptibility to buckling in 20 species of the Pteridaceae. Strong allometric relationships were observed between sterome thickness and leaf size, with the sterome contributing over 97% to petiole flexural rigidity. Surprisingly, the small-statured cheilanthoid ferns allocated the highest fraction of their petiole to the sterome, while large leaves exploited aspects of geometry (second moment of area) to achieve bending resistance. This pattern also revealed an economy of function in which increasing sterome thickness was associated with decreasing fiber cell reinforcement, and fiber wall fraction. Lastly, strong petioles were associated with durable leaves, as approximated by specific leaf area. This study reveals meaningful patterns in fern leaf biomechanics that align with species leaf size, sterome attributes and life-history strategy. [ABSTRACT FROM AUTHOR]

Techniques for in situ localization of gene products provide indispensable information for understanding biological function. In the case of enzymes, biological function is directly related to activity, and therefore, knowledge of activity patterns is central to understanding the molecular controls of plant development. We have previously developed a novel type of fluorogenic substrate for revealing glycoside hydrolase activity in planta, based on resorufin β-glycosides Here, we explore a wider range of such substrates to visualize glycoside hydrolase activities in Arabidopsis inflorescence stems in real time, especially highlighting distinct distribution patterns of these activities in the secondary cell walls of sclerenchyma cells. The results demonstrate that β-1,4-glucosidase, β-1,4-glucanase and β-1,4-galactosidase activities accompany secondary wall deposition. In contrast, xyloglucanase activity follows a different pattern, with the highest signal observed in mature cells, concentrated in the middle lamella. These data further the understanding of the process of cell wall deposition and function in sclerenchymatic tissues of plants.

* Background and Aims A key structural adaptation of vascular plants was the evolution of specialized vascular and mechanical tissues, innovations likely to have generated novel cell wall architectures. While collenchyma is a strengthening tissue typically found in growing organs of angiosperms, a similar tissue occurs in the petiole of the fern Asplenium rutifolium. * Methods The in situ cell wall (ultra)structure and composition of this tissue was investigated and characterized mechanically as well as structurally through nano-indentation and wide-angle X-ray diffraction, respectively. * Key Results Structurally the mechanical tissue resembles sclerenchyma, while its biomechanical properties and molecular composition both share more characteristics with angiosperm collenchyma. Cell wall thickening only occurs late during cell expansion or after cell expansion has ceased. * Conclusions If the term collenchyma is reserved for walls that thicken during expansive growth, the mechanical tissue in A. rutifolium represents sclerenchyma that mimics the properties of collenchyma and has the ability to modify its mechanical properties through sclerification. These results support the view that collenchyma does not occur in ferns and most probably evolved in angiosperms. [ABSTRACT FROM AUTHOR]

Erysimum croceum M. Pop. (Brassicaceae) is an endemic species, growing only in Trans-Ili Alatau. It is included into Kazakhstan Red Data Book. The aim of this study is to compare two populations of Erysimum croceum M.Pop identified in Trans-Ili Alatau region, for which morphological and ecological analysis was undertaken. Plant communities of the 1st population growing in Small Almaty gorge (N43* 06.316', E077* 04.184') are dominated by indigenous plants with a significant proportion of endemic taxa, while the 2nd population from the Big Almaty gorge (N43* 04.790', E076* 59.512') is growing in subruderal positions with the presence of other plants. Statistical analysis of the morphological traits revealed significant differences between the two populations. In this article summary on comparative analysis of the main features of morphological and anatomical structures of endemic species Erysimum croceum is given. To identify the cause of its disappearance we studied seed germination and growth of seedlings. Seed germination is low and only reaches 18 %. Morphological structure of seedlings on the 45th day showed overall length of sprouts 6.67±3.84 cm, hypocotyl length 1.12±0.06 cm, root length 5.49±3.57 cm, leaves length 0.39±0.63 cm, and leaves width 0.2±0.2 cm. The anatomical features of Erysimum croceum were defined. Stem diameter in Erysimum croceum collected from the 1st population equals to 1052.92±11.7 μm, epidermis thickness - 25±0.9 μm, primary cortex thickness - 96.24±0.6 μm, core diameter - 796.51±5.9 μm. Stem diameter in Erysimum croceum collected from the 2nd population equals to 996.38±9.8 μm, epidermis thickness - 21±0.7 μm, primary cortex thickness - 80.98±0.4 μm, center circle diameter - 701.59±8.7 μm. Anatomical sections of rhizome and leaf were compared on virginal and generative stages, while the stem was studied only at generative stage. Main specification into the inner structure is designated by accumulation of sclerenchyma between conducting bundles in central cylinder and alternative location of small and large bundles. [ABSTRACT FROM AUTHOR]

Anatomical investigations of the stem in seven Zea mays L. Inbred lines were performed on specimens bred in the Experimental Institute of Breeding and Plant Acclimatization in Smolice. Two of the lines (bm1 and bm2) including the gene brown midrib were characterized by a higher digestability. The remaining five lines (S215, S335, 5336, S336A and S339) were selective inbred lines used as components in hybrid breeding at the Institute in Smolice. The investigated lines were compared in respect to 50 anatomical traits of the stem. The comparisons were performed by means of the Wrocław dendrite method. The lines formed three distinct groups according to the degree of similarity. The first group consisted of two lines with the gene brown midrib (bm1 and bm2), the second of four lines (5215, S336, S336A and S339), and the third of line S335. The inclusion of both the lines with gene bm into one group was based on similarity regarding the set of traits of parenchyma, particularly of the peripheral part of the stem, as well as metaxylem and metaphloem traits. However, these lines differed considerably in respect to epidermis traits. It was peculiar that the stomata of the Amaryllis type occurred in one of the lines (S339). Each line made a specific mosaic of traits. The sets of traits characterizing the particular lines were specific in such a degree that they could be used, like a fingerprint, for their identification.

· Root neck of rose rootstocks characterize anatomy structure like typically shoots. · Anatomical structure of root neck varies considerably amongst studied taxa. · Irregulary sclerenchyma cells in phloem' neck root were be detected. · Wide rays full of starch grains suggest proper transportation of assimilates. · Wide rays suggest histology impact on fusion proces of components by budding. The budding is the most used method of propagation the rose cultivars especially in temperate zone and cooler climate regions. The cause of the components not joining together are attributed to differences in their anatomical and histological structure. The anatomy of the root necks of rose rootstocks is surveyed and analysed based on the study of five taxa commonly in nursery production: Rosa canina 'Inermis', 'Pfänder', 'Schmid's Ideal', Rosa laxa , and Rosa multiflora. The study focused on the rootstock layers coming into contact with the cultivar scion at budding to form an adhesion. The anatomical structure of the root-neck tissues differs significantly in the studied taxa in terms of the observed tissue elements: earlywood, latewood, pith rays, phloem, vessels, cambium layer. The specific arrangement is shown by layers of sclerenchyma and phloem fibers. Taking into account the anatomical structure of the shoot tissues, the above-mentioned rootstocks can be classified in Group I of the Rosaceae. The tissue structure of earlywood in Rosa canina 'Inermis', 'Pfänder', 'Schmid's Ideal', Rosa laxa indicated reduced growth in the period immediately following rootstock planting in the field in spring, which was influenced by low rainfall in the period from March to the beginning of May. The cambium showed a different but high activity at the time of rootstock harvest, which coincided with the period of budding. The results of the study showing differences in anatomy structure indicate the possibility of a different response to budding and the initiation of adhesion processes. [Display omitted] [ABSTRACT FROM AUTHOR]

The mechanical structure of plant tissues has recently attracted a lot of attention. The present study aims to evaluate the importance of collenchymatous and sclerenchymatous tissues in supporting plant species in their harsh environments like road and street plant habitats. Dicots and monocots are classified into different models according to the types of supporting mechanisms. Mass cell percentage and soil analysis are used in this investigation. The tissues are distributed with different percentage masses and arrangements to overcome various severe conditions. Statistical analyses enhance the role of these tissues and clarify their significant values. The gear support mechanism is claimed to be the perfect mechanical method used. [ABSTRACT FROM AUTHOR]

In this study, leaf micromorphological structure of eight species of Festuca (F. akhanii, F. elwendiana, F. heterophylla, F. sulcata, F. valesiaca, F. arundinacea, F. gigantean and F. drymeia) and leaf anatomy structure of three species of Festuca (F. arundinacea, F. gigantean and F. drymeia) belonging to the four subgenera were examined with different repeations. About 40 quantitative and qualitative anatomical features of the leaves were statistically analyzed for several times from superficial view and on transversal section. These characters included observation of ribs and furrows in epidermis, the density of stomata and trichome, and the arrangement of vascular bundles. Sclerenchyma and bulliform cells were studied and their taxonomic value was verified in order to classify different species. The micromorphology data and anatomy characteristics of the species were used for multivariate analysis, which partly supported the taxonomic treatment of the genus Festuca in the flora of Iran. In order to group the species studied on the basis of similarity in their anatomical features as well as their micro morphological characteristics, different clustering methods of Between Groups, Single Linkage and WARD were observed. The first cluster composed of F. sulcata, F. valesiaca, F. elwendiana, F. heterophylla and F. akhanii. The species of F. arundinacea, F. gigantea and F. drymeia were positioned in clusters two.

Spines are a striking feature of cacti and display wide variation in size, number, shape, and texture. This study showed that Turbinicarpus species exhibit not only a high variability in the gross morphology of the spines, but also in their micro-morphology. Their surface can be smooth or ornamented with projections that can be low, conical, pinnate, or long trichomes. The epidermis can be continuous, broken up into single cell elements or transversely fissured, the fissures extending deeply into the underlying sclerenchyma. The mechanical properties of the spines are related to their anatomy, here documented for the first time. The woody rigid spines being made up of fibers with thick walls (> 3 µm), while papery or corky spines have a sclerenchyma made up of fibers with thin walls (< 2 µm). Alternatively, spine anatomy can be dimorphic with the outermost layers made up of thin-walled fibers and an inner core made up of thick-walled fibers. Turbinicarpus taxonomy mostly relies on spine features and the newly collected data can contribute to a better understanding of the interspecific relationships. The epidermal features like long trichomes or the lack of ornamentation as well as the modified anatomy of corky spines may be apomorphic characters within the genus.Las espinas son una de las características más distintivas de las cactáceas y se distinguen por su variación en tamaño, número, forma y textura. Este estudio muestra que las especies de Turbinicarpus no sólo tienen variación en la morfología de sus espinas, sino también en su micro-morfología. Su superficie puede ser lisa u ornamentada con proyecciones bajas, cónicas, pinadas o bien con tricomas largos. En las espinas, la epidermis se mantiene continua, separada en sus células o transversalmente fisurada. Las fisuras de la epidermis pueden prolongarse hasta el esclerénquima más interno. Las propiedades mecánicas de las espinas están relacionadas con su anatomía, aquí documentada por primera vez. Las espinas rígidas están constituidas de fibras con paredes gruesas (> 3 µm), mientras que las espinas suaves o corchosas, también denominadas cerdas tienen esclerénquima de fibras con paredes delgadas (< 2 µm). Además, algunas espinas en su madurez tienen 2 tipos de fibras, las pobremente lignificadas en la parte externa y en la interna las de paredes gruesas y lignificadas. La taxonomía de Turbinicarpus se basa principalmente en las espinas y los datos aquí generados contribuyen a un mejor entendimiento de sus relaciones interespecíficas. El conocimiento de las características epidermales como los tricomas largos, la carencia de ornamentación o las modificaciones anatómicas de las espinas corchosas pueden interpretarse como caracteres apomórficos en el género.