Palisade Cell Layers Research Articles

Study Of Some Anatomical Features Of Stevia Rebaudiana (Bertoni) Bertoni Grown In Iraq

The leaves of Stevia rebaudiana, from Asteraceae family, are a source of steviol glycosides, which are utilized as a sweeter, more favorite addition. Among the most important anatomical results that were reached through the research and which distinguish the plant from an anatomical point of view are uniseriate-multicellular of non-glandular trichomes that are covered the epidermis of stem and leaves. Also, the vertical walls of the ordinary epidermis cells in the upper and lower epidermis that are heavily sinuous and the stomata scattered in both of it, the type of the stomata anomocytic. In addition, the mesophyll which differentiated into 2-3 layers of palisade cells under the upper epidermis and the spongy cells after it and the cross-section of midrib region of the leaf as crescent shape and the vascular bundle central, crescent shape.

Seeds of the threatened dry rainforest tree Cadellia pentastylis (Surianaceae) are non-dormant

AbstractCadellia pentastylis (Surianaceae) is an Australian endemic threatened rainforest tree. Irregular flowering and fruiting events coupled with high rates of infertility and insect predation has meant that seed testing has not been possible for this species. Seeds were opportunistically collected from a wild population in early 2021, which allowed for the first germination tests to be conducted. In this study, the presence of physical dormancy was examined by performing an imbibition test using scarified and non-scarified seeds. We also investigated whether a 5-min heat shock treatment at temperatures ranging from 60 to 120°C improved germination success. The presence of physiological dormancy was also examined by recording germination success following a gibberellic acid or smoke-water pre-treatment. Both scarified and non-scarified seeds readily imbibed water over a 72-h period, and several seeds had germinated in both treatments after 48 h. Final germination proportion and t50 following a heat shock, gibberellic acid or smoke-water pre-treatment did not significantly differ from the controls. We conclude that C. pentastylis seeds are non-dormant. Although a palisade cell layer has been reported in the endocarp, our results suggest that this layer may not be sufficiently formed to restrict germination. We recommend that seeds are collected from populations following dispersal and propagated shortly after or stored as conservation collections in ex situ Seedbanks.

Identification of the initial water-site and movement in Gleditsia sinensis seeds and its relation to seed coat structure

BackgroundWater uptake is essential for seed germination. However, Gleditsia sinensis seeds have a water-impermeable seed coat, which is beneficial for its adaption to the environment, but prohibits its germination without treatment. This feature may be associated with the structure of the seed coat. Thus, the aim of this research was to identify and describe the initial water uptake site and water movement and to determine the relationship between seed coat structure and water absorption.ResultsA water temperature of 80 °C was optimal to break the hardseededness of G. sinensis seeds. Scanning electron microscopy (SEM) images revealed that the seed coat consisted of a palisade layer and light line that can hinder water entry into the seed. Also, a structure of vascular bundles existed in the hilar region. Hot water treatment caused the tightly closed micropyle to open and the cavity beneath it expanded; the layer of palisade cells in the lens was raised. The embryo dye-tracking tests showed that the radicle tip was the initial region to be stained red. After staining for 24 h, the red-stained area on the vascular bundle side of cotyledon was more extensive than that on the other side. Further studies by MRI maps indicated that the micropyle was the initial site for water imbibition. Some water then migrated along the space between the seed coat and the endosperm to the chalazal; simultaneously, the rest of the water reached the embryonic axis and spread into cotyledons. The maps of 20–24 h showed that water was unevenly distributed within the cotyledons in a way that the edge parts were more hydrated than the center. Blocking tests showed that the hilar region was the initial and an important region during seed imbibition. The medial region and chalazal portion were capable of imbibing water when the hilar region was blocked, but water absorption was later and slower than that through the hilar region.ConclusionMRI technology provides a promising and non-invasive technique to identify the water gap and the path of water movement in the seed. Combined with the results of SEM, the relation between seed coat and its imbibition can be inferred.

Acclimation of mesophyll conductance and anatomy to light during leaf aging in Arabidopsis thaliana.

Mesophyll conductance (gm ), a key limitation to photosynthesis, is strongly driven by leaf anatomy, which is in turn influenced by environmental growth conditions and ontogeny. However, studies examining the combined environment × age effect on both leaf anatomy and photosynthesis are scarce, and none have been carried out in short-lived plants. Here, we studied the variation of photosynthesis and leaf anatomy in the model species Arabidopsis thaliana (Col-0) grown under three different light intensities at two different leaf ages. We found that light × age interaction was significant for photosynthesis but not for anatomical characteristics. Increasing growth light intensities resulted in increases in leaf mass per area, thickness, number of palisade cell layers, and chloroplast area lining to intercellular airspace. Low and moderate-but not high-light intensity had a significant effect on all photosynthetic characteristics. Leaf aging was associated with increases in cell wall thickness (Tcw ) in all light treatments and in increases in leaf thickness in plants grown under low and moderate light intensities. However, gm did not vary with leaf aging, and photosynthesis only decreased with leaf age under moderate and high light, suggesting a compensatory effect between increased Tcw and decreased chloroplast thickness on the total CO2 diffusion resistance.

Anatomical Investigation and GC/MS Analysis of 'Coco de Mer', Lodoicea maldivica (Arecaceae).

Lodoicea maldivica (J.F.Gmel.) Pers. (Arecaceae), 'Coco de Mer', is a palm, growing as endemic in the Seychelles islands. Its fruit weighs up to 20 kg and is characterized by a fleshy and fibrous envelope surrounding the nutlike portion. The present work combines a morpho-anatomical and a phytochemical analysis of the fruit exocarp and mesocarp. The exocarp is composed by a layer of palisade cells. The mesocarp is characterized by vascular bundles and by sclereids. In the aerenchyma, the internal zone of the mesocarp, cells aggregates were positive to phenols, while idioblasts were positive to terpenes. We performed a GC/MS analysis with a semi-quantitative relative amount calculation of the recorded compounds. The GC/MS essential oil profile revealed the dominance of acyclic sesquiterpenoids (53.95 %), followed by bicyclic sesquiterpenoids (31.69 %), monoterpenes (11.89 %) and monocyclic sesquiterpenoids (2.44 %). The terpenes detected in higher amounts, β-caryophyllene and bicyclogermacrene, are known for activity against insect larvae, but have been proposed as antiviral candidates against SARS-CoV-2. The third compound in amount, aromadendrene, is active against bacteria and, again, known to possess insecticidal properties.

Lower photosynthetic capacity under higher spectral reflectance? The case of Actinidia polygama

The variegated leaves of Actinidia polygama exhibit a striking colour change during development. However, little is known whether the photosynthetic capacity of white leaves can be maintained. Therefore, spectrum properties, leaf structure, net photosynthetic rate (PN), and chlorophyll fluorescence in the green and white leaves were investigated. Although reflectance at 400 - 700 nm in white leaves was higher than that in green leaves, total chlorophyll content of white leaves was similar to that in green leaves. Palisade tissue cells of white leaves contained functional chloroplasts. Large intercellular spaces were observed between the epidermal and mesophyll cells and within the palisade tissue cell layer in white leaves. Both PN and the actual quantum yield of photosystem II in white leaves were similar to green leaves. At different leaf growth stages, PN of white leaves was about 88 - 100 % of the PN of green leaves. The efficiency of electron move beyond QA- (ET/TR) and the quantum yield of electron transport (ET/ABS) in white leaves was higher than in green leaves. In conclusion, photosynthetic capacity in white leaves of A. polygama showed two favorable characteristics during the whole sampling period: 1) despite a higher spectral reflectance in white leaves, PN of white leaves remained relatively high compared with green leaves; 2) the higher activity of photosystem II of white leaves enabled photosynthetic capacity maintenance.

Seed Dormancy Breaking and Germination in Bituminaria basaltica and B. bituminosa (Fabaceae)

Most legumes are well-known for the physical dormancy of their seeds; hence, the implementation of appropriate scarification techniques is essential for introducing new legume crops within agricultural systems. This study investigated morpho-anatomical traits and dormancy-breaking requirements in two taxa of the genus Bituminaria: the widespread B. bituminosa and the point endemic B. basaltica. As the species under investigation show monospermic indehiscent legumes, pods were used in this research. We performed pod trait measurements, light microscopy observations on the seed coat anatomical structure, and germination tests after mechanical, thermal, and chemical scarification treatments for seed dormancy breaking. Moreover, germination performance at different pod maturity stages and storage times was tested. Differences in morpho-anatomical traits were found, with B. basaltica having a thicker palisade cell layer and B. bituminosa showing larger pods. All of the scarification treatments proved to be able to break physical dormancy, with mechanical and chemical scarification being the most effective methods in both species. Nevertheless, dormancy-breaking treatments performed better in B. bituminosa. Seeds at early pod maturity stages showed higher germination capacity in both species. Overall, this research provided background knowledge on seed collection time, storage strategy, and effective pre-sowing treatment, which might contribute to enhance propagation and use of Bituminaria species for multiple purposes. Under this perspective, the future characterization of additional Bituminaria genetic resources from other Mediterranean populations will have remarkable importance.

ODONTOGENIC KERATOCYST ASSOCIATED WITH THIRD MOLAR IN MAXILLARY SINUS

A 20-year-old white male patient was admitted to the hospital complaining about intraoral swelling, spontaneous secretion drainage at superior left molar, throbbing pain, local pressure, parageusia, and halitosis 3 months ago. The intraoral physical examination revealed bulging in between teeth 25 to 27 causing slight facial asymmetry. The computed tomography showed ectopy of tooth 28 associated to cystic-like unilocular bone rarefaction, filling in great extension of the left maxillary sinus. The maxillary sinus was accessed through Caldwell-Luc technique followed by the decompression and cyst excision, and the material removed was referred for histopathologic examination. Microscopically, an epithelium-lined pathologic cavity was observed, being 6 to 8 cells thick. The epithelium demonstrated a well-developed basal layer of palisade cells with polarized, hyperchromatic nuclei. The luminal surface was corrugated and contained parakeratin and, thus, diagnosis of odontogenic keratocyst was established. The patient is under follow-up for 4 months without recurrence.

Estructura morfo-anatómica y salida de dormición física de las semillas de Malvastrum coromandelianum ssp. coromandelianum (Malvaceae)

Introducción y objetivos: Uno de los principales problemas para el manejo y uso de muchas especies vegetales es la presencia de semillas con dormición física. En este trabajo estudiamos la presencia de dormición física en mericarpos (unidad de dispersión) y semillas, las estructuras morfo-anatómicas involucradas y los métodos de salida de dormición física en semillas de Malvastrum coromandelianum (Malvaceae).
 M&M: Se realizaron ensayos de imbibición en mericarpos y en semillas intactas y escarificadas. Se describió la estructura morfo-anatómica de las semillas con microscopio electrónico de barrido y se evaluó el efecto de la escarificación mecánica, química y térmica sobre la germinación y estructura de las semillas.
 Resultados: Los mericarpos y las semillas escarificadas incrementaron > 160% su peso inicial, mientras que las semillas intactas incrementaron < 40% su peso. Las semillas presentaron una cubierta con células en empalizada y un complejo de abertura al agua ubicado en la región chalazal. Los mayores porcentajes y menores t 50 se registraron luego de la escarificación mecánica, seguido de la química y térmica (calor seco). Las escarificaciones química y térmica produjeron la eliminación de la tapa chalazal y formación de grietas alrededor de la región chalazal, mientras que la formación y eliminación de una ampolla chalazal sólo se observó luego de la escarificación química.
 Conclusiones: Las semillas de M. coromandelianum presentan dormición física. El ingreso de agua ocurre a través de un complejo de abertura (Tipo III compuesto) en la región chalazal de las semillas. Las escarificaciones mecánica, química y térmica son métodos eficientes para la salida de la dormición física y germinación de semillas.

Mesophyll thickness and sclerophylly among Calotropis procera morphotypes reveal water-saved adaptation to environments

Calotropis procera (Aiton) Dryand (Apocynaceae) is a native species in tropical and subtropical Africa and Asia. However, due to its fast growing and drought-tolerant, it has become an invasive species when it was introduced into Central and South America, as well as the Caribbean Islands. Currently, C. procera displays a wide distribution in the world. Invasiveness is important, in particular, because many invasive species exert a high reproductive pressure on the invaded communities or are highly productive in their new distributed areas. It has been suggested that a very deep root system and a high capacity to reduce stomatal conductance during water shortage could allow this species to maintain the water status required for a normal function. However, the true mechanism behind the successful distribution of C. procera across wet and dry environments is still unknown. C. procera leaves were collected from 12 natural populations in Brazil, Colombia and Mexico, ranging from wet to dry environments during 2014–2015. Many traits of morphology and anatomy from these distinct morphotypes were evaluated. We found that C. procera leaves had a considerable capacity to adjust their morphological, anatomical and physiological traits to different environments. The magnitude of acclimation responses, i.e., plasticity, had been hypothesized to reflect the specialized adaptation of plant species to a particular environment. However, allometric models for leaf area (LA) estimation cannot be grouped as a single model. Leaves are narrower and thicker with low amounts of air spaces inside the leaf parenchyma in wet environments, while they are broader and thinner with a small number of palisade cell layers in dry environments. Based on these, we argue that broader and thinner leaves of C. procera dissipate incident energy at the expense of a higher rate of transpiration to survive in environments in which water is the most limiting factor and to compete in favorable wet environments.

Ultrastructure of plastids serves as reliable abiotic and biotic stress marker.

Plastids perform many essential functions in plant metabolism including photosynthesis, synthesis of metabolites, and stress signaling. The most prominent type in green leaves is the chloroplast which contains thylakoids, plastoglobules, and starch. As these structures are closely linked to the metabolism of chloroplasts, changes during plant growth and development and during environmental stress situations are likely to occur. The aim of this study was to characterize changes in size and ultrastructure of chloroplast on cross-sections of leaves during high light stress, Botrytis infection, and dark induced senescence by quantitative transmission electron microscopy (TEM).The size of chloroplasts on cross sections of leaves decreased significantly when plants were subject to high light (49%), Botrytis infection (58%), and senescence (71%). The number of chloroplasts on cross sections of the palisade cell layer and spongy parenchyma, respectively, decreased significantly in plants exposed to high light conditions (48% and 29%), infected with Botrytis (48% and 46%), and during senescence (78% and 80%). Thylakoids on cross-sections of chloroplasts decreased significantly in plants exposed to high light (22%), inoculated with Botrytis cinerea (36%), and senescence (51%). This correlated with a massive increase in plastoglobules on cross-sections of chloroplasts of 88%, 2,306% and 19,617%, respectively. Starch contents on cross sections of chloroplasts were completely diminished in all three stress scenarios. These results demonstrate that the decrease in the number and size of chloroplasts is a reliable stress marker in plants during abiotic and biotic stress situations which can be easily detected with a light microscope. Further, lack of starch, the occurrence of large plastoglobules and decrease in thylakoids can also be regarded as reliable stress marker in plants which can be detected by TEM.

Use of morphological and anatomical characters to delimit varieties of Paliurus spina-christi Mill. (Rhamnaceae)

Introduction: Paliurus spina-christi Mill is a species with two varieties namely Paliurus spina-christi L. var. spina-christi and Paliurus spina-christivar. macrocarpa Beck native to mountains of Kurdistan, rarely growing in the upper plains of northern Iraq. Materials and Methods: A total of 15 plants from different parts of Kurdistan region were sampled. 30measurements for each characters of Leaf, Inflorescence, Flowers, Fruit, seeds, and leaf anatomical characters were measured for comparison between the two varieties. Results and Discussion: Fruit diameter of var. macrocarpa is significantly larger than fruit diameter of var. spina-christi. Most mean flower parts especially the ovary, in addition to seed size is larger in var. macrocarpa. Upper epidermal layer is always thicker than the lower epidermal layer for the same blade. The isobilateral mesophyll includes 2 layers of long palisade cells adaxially and 2-3 layers of short cells abaxially. Many vascular bundles are seen equally spaced in the mesophyll tissue.With the exception of the presence of simple hairs on the petiole adaxial side of the var. spina-cristi and the absence of these hairs from the same site of var. macrocarpa, all other anatomical features are considered to be of no taxonomic application. Stomatal density of the adaxial leaf side is up to 19 stomata per mm² in var. spina-christi while it is up to 38 stomata per mm² in var. macrocarpa. Conclusions: Both fruit diameter and the stomatal density of the adaxial leaf side constitute diagnostic characters for separating between the two varieties of Paliurus spina-christi Mill

Analysis and comprehensive evaluation on cold resistance of six varieties of Michelia

Taking six varieties of Michelia as test materials, their responses under cold situation in the field were investigated and the semilethal low temperatures were calculated by fitting Logistic equation. The nine structure indexes of leaf tissue were observed by paraffin section, and a comprehensive evaluation on cold resistance of different varieties was given according to subordinate function value analysis. The results showed that the relative electrical conductivity of six varieties of Michelia was significantly positively correlated with the semilethal low temperature (LT50) of 3 h 0-25 ℃ treatment. From high to low, the order of LT50, which ranged between -20.48 ℃and -8.67 ℃, was M. maudiae ＞ M. maudiae var. rubicunda ＞ M. wilsonii ＞ M. 'liubanhanxiao' ♀× M. shiluensis ♂ ＞ M. platypetala ＞ M. 'liubanhanxiao'. The epidermal anticlinal walls of six varieties of Michelia leaves had 1-2 layers and showed slightly sinuated shape. The leaf had 1-3 layers of palisade tissue cells and the differences among the indexes of nine anatomical structures were extremely significant. The thickness of palisade tissue, ratio between palisade tissue and spongy tissue, and thickness of the vein were the key factors affecting cold resistance. The order of cold resistance of six varieties of Michelia, from the strong to the weak, was M. 'liubanhanxiao' ＞ M. platypetala ＞ M. 'liubanhanxiao' ♀× M. shiluensis ♂＞M. wilsonii ＞ M. maudiae var. rubicunda ＞ M. maudiae, which was basically consistent with the result of field investigation.

Anatomical and Physiological Responses of Four Quinoa Cultivars to Salinity at Seedling Stage

Objectives: Salinity is one of the most important environmental stress factors that limits both seed germination and seedling develop. Seedling stage is the most susceptible stage of plants to salt stress. The aim of this work is to study the effect of salt stress on anatomical and physiological features of cotyledons and roots of the seedlings of four quinoa cultivars (Witulla, Wariponcho, Pasankalla and CICA). Methods/ Statistical Analysis: Seed germination and seedling growth was carried out under 0 and 200 mM NaCl during 10 days. Root length and diameter, and root proton extrusion were measured. Soluble sugars and proline concentrations were determined in both cotyledons and roots. Anatomical attributes of cotyledons (adaxial and abaxial stomatal area and density, palisade and spongy cell layers, palisade cell density) and roots (stele diameter and surface, metaxylem vessel diameter) were also analyzed. Findings: Salt stress caused physiological and anatomical changes in cotyledons and roots. Sucrose, glucose and fructose concentrations were more affected in cotyledons than in roots of salt-treated seedlings. Proline accumulation was more affected in roots. Saline stress affected differentially the anatomical attributes of quinoa cultivars. Application/Improvements: Quinoa seedlings when subjected to salt stress are able to develop a set of anatomical, physiological and biochemical adaptive mechanisms which seem to occur at different combinations among quinoa cultivars, but giving similar abilities to cope with the excess of salt and survive under extreme conditions.

Cytohistological study of the leaf structures of Panax ginseng Meyer and Panax quinquefolius L.

BackgroundBoth Panax ginseng Meyer and Panax quinquefolius are obligate shade-loving plants whose natural habitats are broadleaved forests of Eastern Asia and North America. Panax species are easily damaged by photoinhibition when they are exposed to high temperatures or insufficient shade. In this study, a cytohistological study of the leaf structures of two of the most well-known Panax species was performed to better understand the physiological processes that limit photosynthesis. MethodsLeaves of ginseng plants grown in soil and hydroponic culture were sectioned for analysis. Leaf structures of both Panax species were observed using a light microscope, scanning electron microscope, and transmission electron microscope. ResultsThe mesostructure of both P. ginseng and P. quinquefolius frequently had one layer of noncylindrical palisade cells and three or four layers of spongy parenchymal cells. P. quinquefolius contained a similar number of stomata in the abaxial leaf surface but more tightly appressed enlarged grana stacks than P. ginseng contained. The adaxial surface of the epidermis in P. quinquefolius showed cuticle ridges with a pattern similar to that of P. ginseng. ConclusionThe anatomical leaf structure of both P. ginseng and P. quinquefolius shows that they are typical shade-loving sciophytes. Slight differences in chloroplast structure suggests that the two different species can be authenticated using transmission electron microscopy images, and light-resistant cultivar breeding can be performed via controlling photosynthesis efficiency.

Paths of water entry and structures involved in the breaking of seed dormancy of Lupinus

Physical dormancy is the water impermeability of the seed coat caused by one or more palisade cell layer(s) called macrosclereids. The specialised structure for water entry sites is the water gap, which serves as a detector of environmental cues for germination. In Fabaceae, the water gap is the lens, although another seed structure for water entry could exist. In this study, we identified the initial site of water entry, observed the hydration of a cushion-like structure near the radicle, described the anatomy of the water gap, and analysed the association of anatomical seed traits with the initial site of water entry and the imbibition velocity of six species of Lupinus from the state of Jalisco, Mexico. Dye tracking with a toluidine blue solution was used to identify the initial site of water entry. The anatomical description was performed using conventional microtechnique and a light microscope. The entry of the toluidine solution into seeds of L. montanus was observed after 6h, followed by L. exaltatus and L. mexicanus after 18h and L. elegans, L. reflexus and L. rotundiflorus after 48h. The site of water entry was the lens in L. elegans, L. exaltatus, L. reflexus and L. rotundiflorus and the micropyle in L. mexicanus and L. montanus. The cushion-like structure was responsible for water accumulation in embryo imbibition. Significant differences among anatomical seed traits such as thickness in the hilar region, the counter-palisade layer, cushion-like structure, epidermis, hypodermis, and innermost parenchyma layer were found among the species.

Actinidia kolomikta leaf colour and optical characteristics

Actinidia kolomikta (Rupr. & Maxim.) Maxim. leaves showed dramatic colour changes during plant growth phases, and we studied structure and optical properties of variegated leaves. Leaf surface cells were smooth, and there were no surface appendages (wax or trichomes) observed in variegated leaves. Palisade tissue cells in white and pink leaves were looser and contained relatively fewer chloroplasts. White leaves contained many intercellular spaces between the epidermal and mesophyll cells or within the palisade cell layer. Variegated leaves had three distinct radiation reflection patterns: a bright white area, a spotted pattern, and a polygonal pattern. Reflectance at 450–1100 nm from the adaxial surface of white leaves was greater than that of green leaves, but anthocyanin accumulation in pink leaves decreased the reflectance at 500–600 nm. When variegated leaves turned green, the reflectance at 500–600 nm increased. On abaxial surfaces, the reflectance of variegated leaves was similar to green leaves at 450–700 nm. In conclusion, reflection patterns and the formation of variegated leaves of A. kolomikta were significantly correlated with the leaf anatomy. The white and pink colours of leaves were a result of an internal reflection between air spaces and cells in the leaves, chlorophyll deficiency in palisade tissue, and anthocyanin accumulation. Variegated leaves turned green when the chlorophyll content in palisade tissue increased.

A Single-Nucleotide Polymorphism in an Endo-1,4-β-Glucanase Gene Controls Seed Coat Permeability in Soybean.

Physical dormancy, a structural feature of the seed coat known as hard seededness, is an important characteristic for adaptation of plants against unstable and unpredictable environments. To dissect the molecular basis of qHS1, a quantitative trait locus for hard seededness in soybean (Glycine max (L) Merr.), we developed a near-isogenic line (NIL) of a permeable (soft-seeded) cultivar, Tachinagaha, containing a hard-seed allele from wild soybean (G. soja) introduced by successive backcrossings. The hard-seed allele made the seed coat of Tachinagaha more rigid by increasing the amount of β-1,4-glucans in the outer layer of palisade cells of the seed coat on the dorsal side of seeds, known to be a point of entrance of water. Fine-mapping and subsequent expression and sequencing analyses revealed that qHS1 encodes an endo-1,4-β-glucanase. A single-nucleotide polymorphism (SNP) introduced an amino acid substitution in a substrate-binding cleft of the enzyme, possibly reducing or eliminating its affinity for substrates in permeable cultivars. Introduction of the genomic region of qHS1 from the impermeable (hard-seeded) NIL into the permeable cultivar Kariyutaka resulted in accumulation of β-1,4-glucan in the outer layer of palisade cells and production of hard seeds. The SNP allele found in the NIL was further associated with the occurrence of hard seeds in soybean cultivars of various origins. The findings of this and previous studies may indicate that qHS1 is involved in the accumulation of β-1,4-glucan derivatives such as xyloglucan and/or β-(1,3)(1,4)-glucan that reinforce the impermeability of seed coats in soybean.

Comparing and authenticating on anatomical aspects of Abrus cantoniensis and Abrus mollis by microscopy.

Background:Abrus cantoniensis is popularly used as traditional Chinese medicine and a cool tea in South of China. However, due to diminishing source of A. cantoniensis, it is usually interchanged or adulterated with other species of Abrus genus because of the limited knowledge in identification and differentiation. Especially, Abrus mollis is widely mixed on herbal markets and pharmaceutical preparation.Objective:To ensure safety and efficacy, a detailed comparison was undertaken to carry out an anatomical and micro-morphological study of two species of A. cantoniensis and A. mollis.Materials and Methods:Microscopic characteristics of roots, leaves and stems, including transverse sections and the crude drug powder, were observed using a light microscope according to the usual microscopic techniques.Results:The basic diagnostic features of A. cantoniensis include that stem is extremely thin; xylem vessels of root are radially arranged in 10 or more bundles; pith is hollow in stem, and the palisade tissue is made up of two layers of palisade cells. Furthermore, scanning electron microscopy was used to compare nonglandular hairs and the stomata of the leaflet surface. A table of the key authentication parameters based on the analyzed microscopic characteristics was drawn up.Conclusion:The study demonstrated that the microscopy and related techniques provided a systematic method that is convenient, feasible, and can be unambiguously applied to the authentication of the species of Abrus.

Synchrotron X-ray computed laminography of the three-dimensional anatomy of tomato leaves.

Synchrotron radiation computed laminography (SR-CL) is presented as an imaging method for analyzing the three-dimensional (3D) anatomy of leaves. The SR-CL method was used to provide 3D images of 1-mm² samples of intact leaves at a pixel resolution of 750nm. The method allowed visualization and quantitative analysis of palisade and spongy mesophyll cells, and showed local venation patterns, aspects of xylem vascular structure and stomata. The method failed to image subcellular organelles such as chloroplasts. We constructed 3D computer models of leaves that can provide a basis for calculating gas exchange, light penetration and water and solute transport. The leaf anatomy of two different tomato genotypes grown in saturating light conditions was compared by 3D analysis. Differences were found in calculated values of tissue porosity, cell number density, cell area to volume ratio and cell volume and cell shape distributions of palisade and spongy cell layers. In contrast, the exposed cell area to leaf area ratio in mesophyll, a descriptor that correlates to the maximum rate of photosynthesis in saturated light conditions, was no different between spongy and palisade cells or between genotypes. The use of 3D image processing avoids many of the limitations of anatomical analysis with two-dimensional sections.