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1.
BMC Plant Biol ; 24(1): 566, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38880875

RESUMEN

BACKGROUND: Plants can retain atmospheric particulate matter (PM) through their unique foliar microstructures, which has a profound impact on the phyllosphere microbial communities. Yet, the underlying mechanisms linking atmospheric particulate matter (PM) retention by foliar microstructures to variations in the phyllosphere microbial communities remain a mystery. In this study, we conducted a field experiment with ten Ulmus lines. A series of analytical techniques, including scanning electron microscopy, atomic force microscopy, and high-throughput amplicon sequencing, were applied to examine the relationship between foliar surface microstructures, PM retention, and phyllosphere microbial diversity of Ulmus L. RESULTS: We characterized the leaf microstructures across the ten Ulmus lines. Chun exhibited a highly undulated abaxial surface and dense stomatal distribution. Langya and Xingshan possessed dense abaxial trichomes, while Lieye, Zuiweng, and Daguo had sparsely distributed, short abaxial trichomes. Duomai, Qingyun, and Lang were characterized by sparse stomata and flat abaxial surfaces, whereas Jinye had sparsely distributed but extensive stomata. The mean leaf retention values for total suspended particulate (TSP), PM2.5, PM2.5-10, PM10-100, and PM> 100 were 135.76, 6.60, 20.10, 90.98, and 13.08 µg·cm- 2, respectively. Trichomes substantially contributed to PM2.5 retention, while larger undulations enhanced PM2.5-10 retention, as evidenced by positive correlations between PM2.5 and abaxial trichome density and between PM2.5-10 and the adaxial raw microroughness values. Phyllosphere microbial diversity patterns varied among lines, with bacteria dominated by Sediminibacterium and fungi by Mycosphaerella, Alternaria, and Cladosporium. Redundancy analysis confirmed that dense leaf trichomes facilitated the capture of PM2.5-associated fungi, while bacteria were less impacted by PM and struggled to adhere to leaf microstructures. Long and dense trichomes provided ideal microhabitats for retaining PM-borne microbes, as evidenced by positive feedback loops between PM2.5, trichome characteristics, and the relative abundances of microorganisms like Trichoderma and Aspergillus. CONCLUSIONS: Based on our findings, a three-factor network profile was constructed, which provides a foundation for further exploration into how different plants retain PM through foliar microstructures, thereby impacting phyllosphere microbial communities.


Asunto(s)
Microbiota , Material Particulado , Hojas de la Planta , Ulmus , Hojas de la Planta/microbiología , Hojas de la Planta/ultraestructura , Ulmus/microbiología , Microscopía Electrónica de Rastreo , Bacterias/clasificación , Bacterias/genética , Biodiversidad
2.
BMC Plant Biol ; 24(1): 694, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39039438

RESUMEN

BACKGROUND: This study was aimed to determine the taxonomic position and delimitation of fifteen Lamiaceae taxa using leaf epidermal morpho-anatomical features in Lahore. A main objective of the study was also the revision and upgradation of Lamiaceae taxa in the flora of Pakistan, as no details of studied species are found in the flora of Pakistan. METHODS: The examination of significant anatomical parameters, such as epidermal cell shape and size, stomatal types, guard and subsidiary cells shape and size, stomatal cavity size, trichome size and shape, oil droplets, crystals, and secretory cavity characteristics were studied using light microscopic (LM) and scanning electron microscopic (SEM) techniques. Among all the studied Lamiaceae species, these anatomical features varied significantly. Principal component analysis and correlation were done to distinguish the species' similarities. RESULTS: Most species had pentagonal and hexagonal epidermal cells with straight anticlinal wall thickness. On the adaxial surface, paracytic stomata were found in Ocimum basilicum L. and Rosmarinus officinalis L. Diacytic stomata was observed in Ajuga reptans L. and anisocytic stomata in Galeopsis tetrahit L. In the abaxial surface, trichomes were present in five species, i.e., Mentha suaveolens Ehrh. A. reptans, Thymus vulgaris L., M. haplocalyx, and Salvia splendens Ewat. In S. splendens, peltate and glandular trichomes were seen whereas, in other species, trichomes were long, unbranched glandular and had tapering ends. In adaxial side trichomes were present only in M. suaveolens, A. reptans, S. bazyntina, O. basciculum, S. splendens, S. officinalis, S. rosemarinus. In other species, trichomes were absent on the adaxial surface. In abaxial view, M. suaveolens had the largest length of trichomes, and O. basciculum had the smallest. S. splendens L. had the largest trichome width, while T. vulgaris had the smallest. CONCLUSION: Hence, according to these findings, morpho-anatomical traits are useful for identifying Lamiaceae taxa. Also, there is a need of upgradation and addition of studied taxa in flora of Pakistan comprehensively.


Asunto(s)
Lamiaceae , Hojas de la Planta , Pakistán , Lamiaceae/anatomía & histología , Lamiaceae/ultraestructura , Hojas de la Planta/anatomía & histología , Hojas de la Planta/ultraestructura , Estomas de Plantas/anatomía & histología , Estomas de Plantas/ultraestructura , Microscopía Electrónica de Rastreo , Tricomas/anatomía & histología , Tricomas/ultraestructura , Epidermis de la Planta/anatomía & histología , Epidermis de la Planta/ultraestructura
3.
Ann Bot ; 133(4): 621-642, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38366151

RESUMEN

BACKGROUND AND AIMS: Extrafloral nectaries are nectar-secreting structures present on vegetative parts of plants which provide indirect defences against herbivore attack. Extrafloral nectaries in Clerodendrum chinense are patelliform-shaped specialized trichomatous structures. However, a complete understanding of patelliform extrafloral nectaries in general, and of C. chinense in particular, has not yet been established to provide fundamental insight into the cellular physiological machinery involved in nectar biosynthesis and secretory processes. METHODS: We studied temporal changes in the morphological, anatomical and ultrastructural features in the architectures of extrafloral nectaries. We also compared metabolite profiles of extrafloral nectar, nectary tissue, non-nectary tissue and phloem sap. Further, both in situ histolocalization and normal in vitro activities of enzymes related to sugar metabolism were examined. KEY RESULTS: Four distinct tissue regions in the nectar gland were revealed from histochemical characterization, among which the middle nectariferous tissue was found to be the metabolically active region, while the intermediate layer was found to be lipid-rich. Ultrastructural study showed the presence of a large number of mitochondria along with starch-bearing chloroplasts in the nectariferous region. However, starch depletion was noted with progressive maturation of nectaries. Metabolite analysis revealed compositional differences among nectar, phloem sap, nectary and non-nectary tissue. Invertase activity was higher in secretory stages and localized in nectariferous tissue and adjacent region. CONCLUSIONS: Our study suggests extrafloral nectar secretion in C. chinense to be both eccrine and merocrine in nature. A distinct intermediate lipid-rich layer that separates the epidermis from nectary parenchyma was revealed, which possibly acts as a barrier to water flow in nectar. This study also revealed a distinction between nectar and phloem sap, and starch could act as a nectar precursor, as evidenced from enzymatic and ultrastructural studies. Thus, our findings on changing architecture of extrafloral nectaries with temporal secretion revealed a cell physiological process involved in nectar biosynthesis and secretion.


Asunto(s)
Clerodendrum , Hojas de la Planta , Néctar de las Plantas , Néctar de las Plantas/metabolismo , Clerodendrum/metabolismo , Clerodendrum/ultraestructura , Hojas de la Planta/ultraestructura , Hojas de la Planta/metabolismo , Hojas de la Planta/anatomía & histología
4.
Ann Bot ; 134(1): 131-150, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38551515

RESUMEN

BACKGROUND AND AIMS: Structural colour is responsible for the remarkable metallic blue colour seen in the leaves of several plants. Species belonging to only ten genera have been investigated to date, revealing four photonic structures responsible for structurally coloured leaves. One of these is the helicoidal cell wall, known to create structural colour in the leaf cells of five taxa. Here we investigate a broad selection of land plants to understand the phylogenetic distribution of this photonic structure in leaves. METHODS: We identified helicoidal structures in the leaf epidermal cells of 19 species using transmission electron microscopy. Pitch measurements of the helicoids were compared with the reflectance spectra of circularly polarized light from the cells to confirm the structure-colour relationship. RESULTS: By incorporating species examined with a polarizing filter, our results increase the number of taxa with photonic helicoidal cell walls to species belonging to at least 35 genera. These include 19 monocot genera, from the orders Asparagales (Orchidaceae) and Poales (Cyperaceae, Eriocaulaceae, Rapateaceae) and 16 fern genera, from the orders Marattiales (Marattiaceae), Schizaeales (Anemiaceae) and Polypodiales (Blechnaceae, Dryopteridaceae, Lomariopsidaceae, Polypodiaceae, Pteridaceae, Tectariaceae). CONCLUSIONS: Our investigation adds considerably to the recorded diversity of plants with structurally coloured leaves. The iterative evolution of photonic helicoidal walls has resulted in a broad phylogenetic distribution, centred on ferns and monocots. We speculate that the primary function of the helicoidal wall is to provide strength and support, so structural colour could have evolved as a potentially beneficial chance function of this structure.


Asunto(s)
Evolución Biológica , Pared Celular , Filogenia , Hojas de la Planta , Hojas de la Planta/ultraestructura , Hojas de la Planta/anatomía & histología , Pared Celular/ultraestructura , Microscopía Electrónica de Transmisión , Color , Epidermis de la Planta/ultraestructura
5.
Plant Cell Rep ; 43(5): 135, 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38704787

RESUMEN

KEY MESSAGE: The disruption of the SWL1 gene leads to a significant down regulation of chloroplast and secondary metabolites gene expression in Arabidopsis thaliana. And finally results in a dysfunction of chloroplast and plant growth. Although the development of the chloroplast has been a consistent focus of research, the corresponding regulatory mechanisms remain unidentified. In this study, the CRISPR/Cas9 system was used to mutate the SWL1 gene, resulting in albino cotyledons and variegated true leaf phenotype. Confocal microscopy and western blot of chloroplast protein fractions revealed that SWL1 localized in the chloroplast stroma. Electron microscopy indicated chloroplasts in the cotyledons of swl1 lack well-defined grana and internal membrane structures, and similar structures have been detected in the albino region of variegated true leaves. Transcriptome analysis revealed that down regulation of chloroplast and nuclear gene expression related to chloroplast, including light harvesting complexes, porphyrin, chlorophyll metabolism and carbon metabolism in the swl1 compared to wild-type plant. In addition, proteomic analysis combined with western blot analysis, showed that a significant decrease in chloroplast proteins of swl1. Furthermore, the expression of genes associated with secondary metabolites and growth hormones was also reduced, which may be attributed to SWL1 associated with absorption and fixation of inorganic carbon during chloroplast development. Together, the above findings provide valuable information to elucidate the exact function of SWL1 in chloroplast biogenesis and development.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Cloroplastos , Regulación de la Expresión Génica de las Plantas , Biogénesis de Organelos , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Clorofila/metabolismo , Proteínas de Cloroplastos/metabolismo , Proteínas de Cloroplastos/genética , Cloroplastos/metabolismo , Cloroplastos/ultraestructura , Cotiledón/genética , Cotiledón/metabolismo , Cotiledón/crecimiento & desarrollo , Sistemas CRISPR-Cas , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/ultraestructura , Proteómica
6.
Cells ; 13(11)2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38891083

RESUMEN

The differential effects of cellular and ultrastructural characteristics on the optical properties of adaxial and abaxial leaf surfaces in the genus Tradescantia highlight the intricate relationships between cellular arrangement and pigment distribution in the plant cells. We examined hyperspectral and chlorophyll a fluorescence (ChlF) kinetics using spectroradiometers and optical and electron microscopy techniques. The leaves were analysed for their spectral properties and cellular makeup. The biochemical compounds were measured and correlated with the biophysical and ultrastructural features. The main findings showed that the top and bottom leaf surfaces had different amounts and patterns of pigments, especially anthocyanins, flavonoids, total phenolics, chlorophyll-carotenoids, and cell and organelle structures, as revealed by the hyperspectral vegetation index (HVI). These differences were further elucidated by the correlation coefficients, which influence the optical signatures of the leaves. Additionally, ChlF kinetics varied between leaf surfaces, correlating with VIS-NIR-SWIR bands through distinct cellular structures and pigment concentrations in the hypodermis cells. We confirmed that the unique optical properties of each leaf surface arise not only from pigmentation but also from complex cellular arrangements and structural adaptations. Some of the factors that affect how leaves reflect light are the arrangement of chloroplasts, thylakoid membranes, vacuoles, and the relative size of the cells themselves. These findings improve our knowledge of the biophysical and biochemical reasons for leaf optical diversity, and indicate possible implications for photosynthetic efficiency and stress adaptation under different environmental conditions in the mesophyll cells of Tradescantia plants.


Asunto(s)
Hojas de la Planta , Tradescantia , Tradescantia/metabolismo , Hojas de la Planta/metabolismo , Hojas de la Planta/ultraestructura , Fluorescencia , Clorofila/metabolismo , Clorofila A/metabolismo
7.
Protoplasma ; 261(4): 655-669, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38217740

RESUMEN

Quinoa is a facultative halophyte with excellent tolerance to salinity. In this study, the epidermal bladder cell complex (EBCc) of quinoa leaves was studied to determine their cellular characteristics and involvement in salt tolerance. We used light microscopy, confocal RAMAN microscopy, confocal fluorescence microscopy, transmission electron microscopy, and environmental scanning electron microscopy complemented by energy dispersive X-ray analysis. Ionic content was quantified with flame atomic absorption spectroscopy and with flame emission photometry. Results show that: (i) the number of EBCcs remains constant but their density and area vary with leaf age; (ii) stalk cells store lipids and exhibit thick walls, bladder cells present carotenes in small vesicles, oxalate crystals in vacuoles and lignin in their walls and both stalk and bladder cells have cuticles that differ in wax and cutin content; (iii) chloroplasts containing starch can be found on both stalk and bladder cells, and the latter also presents grana; (iv) plasmodesmata are observed between the stalk cell and the bladder cell, and between the epidermal cell and the stalk cell, and ectodesmata-like structures are observed on the bladder cell. Under high salinity conditions, (v) there is a clear tendency to accumulate greater amounts of K+ with respect to Na+ in the bladder cell; (vi) stalk cells accumulate similar amounts of K+ and Na+; (vii) Na+ accumulates mainly in the medullary parenchyma of the stem. These results add knowledge about the structure, content, and role of EBCc under salt stress, and surprisingly present the parenchyma of the stem as the main area of Na+ accumulation.


Asunto(s)
Chenopodium quinoa , Epidermis de la Planta , Chenopodium quinoa/metabolismo , Chenopodium quinoa/química , Epidermis de la Planta/ultraestructura , Epidermis de la Planta/citología , Epidermis de la Planta/metabolismo , Estrés Salino , Cationes , Hojas de la Planta/ultraestructura , Hojas de la Planta/metabolismo , Salinidad
8.
Micron ; 183: 103657, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-38735105

RESUMEN

New data were obtained on specific bionanostructures, cutinsomes, which are involved in the formation of cuticles on the surface of leaf blades and pericarp of Malus domestica Borkh (Malus Mill., Rosaceae)introduced to the mountains at the altitudes of 1200 and 1700 m above sea level. Cutinsomes, which are electron-dense structures of spherical shape, have been identified by transmission electron microscopy. It was demonstrated that plastids can be involved in the synthesis of their constituent nanocomponents. The greatest number of nanoparticles was observed in the granal thylakoid lumen of the chloroplasts in palisade mesophyll cells and pericarp hypodermal cells. The transmembrane transport of cutinsomes into the cell wall cuticle proper by exocytosis has been visualized for the first time. The plasma membrane is directly involved in the excretion of nanostructures from the cell. Nanoparticles of cutinsomes in the form of necklace-like formations line up in a chain near cell walls, merge into larger conglomerates and are loaded into plasmalemma invaginations, and then, in membrane packing, they move into the cuticle, which covers both outer and inner cell walls of external tissues. The original materials obtained by us supplement the ideas about the non-enzymatic synthesis of cuticle components available in the literature and expand the cell compartment geography involved in this process.


Asunto(s)
Malus , Microscopía Electrónica de Transmisión , Hojas de la Planta , Hojas de la Planta/ultraestructura , Hojas de la Planta/metabolismo , Malus/ultraestructura , Malus/metabolismo , Transporte Biológico , Pared Celular/ultraestructura , Pared Celular/metabolismo , Cloroplastos/ultraestructura , Cloroplastos/metabolismo , Membrana Celular/ultraestructura , Membrana Celular/metabolismo , Plastidios/ultraestructura , Plastidios/metabolismo
9.
Microsc Res Tech ; 87(8): 1889-1903, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38556928

RESUMEN

This article describes detailed and novel data on the anatomy and histochemistry of leaves, stems, and roots of Camonea umbellata (L.) A.R.Simões & Staples in different environments for the identification of characters with taxonomical value and of ecological importance, with provision of light and scanning electron microscopy images. To analyze the characters, we collected samples of the vegetative organs of three individuals in each of three populations, which were in a grazing area, an urban environment, and a biological reserve. The main diagnostic anatomical markers for the identification of C. umbellata include amphistomatic leaves, tetracytic and brachyparatetracytic stomata, peltate trichomes, long simple trichomes, epidermis with striated cuticle ornamentation, mesophyll with acute borders, presence of druses, secretory channels, angular collenchyma, fibrous pericycle in the stem, intraxylary phloem in the vegetative organs, oil bodies throughout the midrib, petiole, stem and root, and epicuticular waxes of the crust and coiled rodlet types. Since the characters above did not show variation in the environments evaluated, we consider these characters taxonomically useful for the identification of C. umbellata. RESEARCH HIGHLIGHTS: The anatomy of the aerial vegetative organs of Camonnea umbellata retains common Convolvulaceae characters. The sinuosity of the epidermal cell walls and the density of trichomes in the epidermis of the petiole were visually variable characters among the analyzed individuals. Amphistomatic leaves, tetracytic and brachyparatetracytic stomata, peltate trichomes, epidermis with striated cuticle ornamentation, dorsiventral mesophyll with border acute, presence of druses, secretory structures, angular collenchyma, fibrous pericycle in the stem, intraxillary phloem, presence of oil bodies in all organs, and epicuticular waxes of the crust type and coiled rods were considered important anatomical markers for the recognition and correct identification of Camonea umbellata.


Asunto(s)
Microscopía Electrónica de Rastreo , Microscopía , Hojas de la Planta , Raíces de Plantas , Tallos de la Planta , Tricomas , Hojas de la Planta/anatomía & histología , Hojas de la Planta/ultraestructura , Tallos de la Planta/anatomía & histología , Tallos de la Planta/ultraestructura , Tricomas/ultraestructura , Tricomas/anatomía & histología , Raíces de Plantas/anatomía & histología , Raíces de Plantas/ultraestructura , Estomas de Plantas/ultraestructura , Estomas de Plantas/anatomía & histología , Epidermis de la Planta/ultraestructura , Epidermis de la Planta/anatomía & histología
10.
Microsc Res Tech ; 87(8): 1849-1861, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38533861

RESUMEN

The order Sapindales is comprised of nine families and in Brazil it is represented by six, including Rutaceae Juss., which constitutes the largest group of this order. A variety of species of Zanthoxylum L. are distributed throughout the country, and among them is the species Zanthoxylum kleinii (R.S. Cowan) P.G. Waterman, which is found in the states of Brazil. This study aimed to characterize the morphoanatomy of the leaf, petiole, rachis, and stem of the species Z. kleinii. Histochemical tests were performed, and the sections were visualized under optical and scanning electron microscopy. The analysis showed that the morphoanatomical characteristics of the species are: hypoestomatic leaflets; stomata classified as anomocytic, tetracytic, and anisocytic; dorsiventral mesophyll; cavities that produce a secretion of lipid nature, present in the leaflet, rachis, and petiole; colleters distributed in the leaf; presence of simple non-glandular trichomes in all structures; and prismatic crystals in the petiole. Histochemical tests indicated the presence of phenolic and lipophilic compounds, mucilage, and lignin. With the result of this research, it was possible to identify the nature of the compounds secreted by the secretory structures of the leaves; in addition, the morphoanatomical characterization of Z. kleinii can provide relevant data for future studies for other organs of the species not yet described. Furthermore, contributing concomitantly with data for the genus, in this way, supporting to differentiate them. RESEARCH HIGHLIGHTS: Ultrastructural features observed by microscopic techniques. Calcium oxalate crystals present in the rachis. Microchemical tests confirmed the presence of colleters in the leaflet.


Asunto(s)
Microscopía Electrónica de Rastreo , Hojas de la Planta , Zanthoxylum , Hojas de la Planta/anatomía & histología , Hojas de la Planta/ultraestructura , Hojas de la Planta/química , Zanthoxylum/química , Zanthoxylum/anatomía & histología , Zanthoxylum/ultraestructura , Brasil , Tallos de la Planta/anatomía & histología , Tallos de la Planta/ultraestructura , Tallos de la Planta/química , Microscopía , Tricomas/ultraestructura , Tricomas/anatomía & histología
11.
Microsc Res Tech ; 87(7): 1640-1646, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38450874

RESUMEN

The classification and identification of Aster glehnii F. Schmidt are determined from its foliar epidermal anatomical features. Scanning electronic microscopy has been used to determine the foliar epidermal anatomical characteristics of the species in detail. This study compared the qualitative and quantitative characteristics of the leaf epidermis of A. glehnii for taxonomic identification to be used as a reference for future studies on the species. A. glehnii has smooth, thin cuticles, depressed anomocytic stomata dispersed randomly throughout the leaf surface, polygonal epidermal cells with straight to slightly curved anticlinal walls, and no trichomes. There are obvious veins containing thick-walled bundle sheath cells. The stomatal density is between 100 and 150 stomata per millimeter. The vein density ranges from five to 10 veins per millimeter, and the epidermal cells are 10 to 20 µm long and 5 to 10 µm in width. Understanding the connections between the different A. glehnii species and categorizing and identifying them depend heavily on these foliar epidermal structural features. Taxonomy and conservation are closely intertwined because the former serves as the basis for comprehending and safeguarding biodiversity. RESEARCH HIGHLIGHTS: Optical microscopy of the A. glehnii leaf epidermis for taxonomic identification SEM was used to identify and authenticate endemic species Microscopic identification of endemic species can assist in the conservation.


Asunto(s)
Microscopía Electrónica de Rastreo , Epidermis de la Planta , Hojas de la Planta , Estomas de Plantas , Hojas de la Planta/anatomía & histología , Hojas de la Planta/ultraestructura , Hojas de la Planta/citología , Epidermis de la Planta/ultraestructura , Epidermis de la Planta/anatomía & histología , Epidermis de la Planta/citología , Estomas de Plantas/anatomía & histología , Estomas de Plantas/ultraestructura , Asteraceae/anatomía & histología , Asteraceae/citología , Asteraceae/clasificación , Asteraceae/ultraestructura
12.
Microsc Res Tech ; 87(9): 2143-2153, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38706034

RESUMEN

In the Medicago genus, saponins are complex mixtures of triterpene pentacyclic glycosides extensively studied for their different and economically relevant biological and pharmaceutical properties. This research is aimed at determining for the first time the tissue and cellular localization of triterpene saponins in vegetative organs of Medicago truncatula, a model plant species for legumes, by histochemistry and transmission electron microscopy. The results showed that saponins are present mainly in the palisade mesophyll layer of leaves, whereas in stems they are mostly located in the primary phloem and the subepidermal cells of cortical parenchyma. In root tissue, saponins occur in the secondary phloem region. Transmission electron microscopy revealed prominent saponin accumulation within the leaf and stem chloroplasts, while in the roots the saponins are found in the vesicular structures. Our results demonstrate the feasibility of using histochemistry and transmission electron microscopy to localize M. truncatula saponins at tissue and cellular levels and provide important information for further studies on biosynthesis and regulation of valuable bioactive saponins on agronomic relevant Medicago spp., such as alfalfa (Medicago sativa L.). RESEARCH HIGHLIGHTS: The Medicago genus represents a valuable rich source of saponins, one of the most interesting groups of secondary plant metabolites, which possess relevant biological and pharmacological properties. Plant tissue and cellular localization of saponins is of great importance to better understand their biological functions, biosynthetic pathway, and regulatory mechanisms. We elucidate the localization of saponins in Medicago truncatula with histochemical and transmission electron microscopy studies.


Asunto(s)
Medicago truncatula , Microscopía Electrónica de Transmisión , Hojas de la Planta , Raíces de Plantas , Saponinas , Triterpenos , Medicago truncatula/ultraestructura , Medicago truncatula/metabolismo , Medicago truncatula/química , Saponinas/metabolismo , Triterpenos/metabolismo , Triterpenos/química , Raíces de Plantas/química , Raíces de Plantas/ultraestructura , Hojas de la Planta/química , Hojas de la Planta/ultraestructura , Tallos de la Planta/química , Tallos de la Planta/ultraestructura , Floema/ultraestructura , Floema/química , Floema/metabolismo , Histocitoquímica , Cloroplastos/ultraestructura , Cloroplastos/metabolismo , Cloroplastos/química
13.
Braz. j. biol ; 78(4): 706-717, Nov. 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-951594

RESUMEN

Abstract Vegetative aerial organs are considerably more exposed to environmental conditions and can reflect the specific adaptations of plants to their local environment. Aldama grandiflora species are known to be widely distributed in Brazil; therefore, individuals from different populations of this species are thought to be exposed to different abiotic and biotic conditions. Several anatomical studies conducted on Brazilian Aldama species have mainly focused on the qualitative anatomical characters or traits of these species, but not on their quantitative traits. In this study, we evaluated whether climate and soil conditions can change the morphometry among individuals of A. grandiflora collected from six sites in the Goiás State, Brazil, by assessing their anatomical characters. Further, soil sampling was performed, and climate data were collected from all the six sites. The analysis indicated few statistical differences among the populations evaluated, showing that A. grandiflora presented consistent leaf and stem anatomical characteristics. The small morpho-anatomical differences found among individuals of the different populations evaluated, reflected the soil conditions in which these populations were grown. Therefore, environmental factors have a significant influence on the morpho-anatomy of Aldama grandiflora.


Resumo Os órgãos vegetativos aéreos estão consideravelmente mais expostos às condições ambientais e podem refletir as adaptações específicas das plantas ao seu habitat. A espécie Aldama grandiflora é amplamente distribuída no Brasil e, dessa forma, indivíduos de diferentes populações podem estar expostos a diferentes condições ambientais. Vários estudos anatômicos realizados com espécies brasileiras do gênero Aldama têm abordado, principalmente, as características anatômicas qualitativas dessas espécies, mas não em suas características quantitativas. Neste estudo avaliamos se as condições climáticas e do solo podem alterar a morfometria entre os indivíduos de A. grandiflora coletados em seis populações do Estado de Goiás. Foram avaliados os caracteres anatômicos foliares e caulinares, além da amostragem do solo e coleta de dados climáticos, para os seis locais. A análise indicou algumas diferenças estatísticas entre as populações avaliadas, mostrando que A. grandiflora apresentou características anatômicas foliares e caulinares bastante consistentes. As pequenas diferenças morfo-anatômicas encontradas entre indivíduos das diferentes populações avaliadas, refletiram as condições do solo nos quais essas populações se desenvolveram. Assim sendo, fatores ambientais relacionados ao clima e condições do solo têm uma influência significativa sobre a morfo-anatomia de Aldama grandiflora.


Asunto(s)
Suelo , Adaptación Fisiológica/fisiología , Clima , Asteraceae/fisiología , Brasil , Tallos de la Planta/fisiología , Tallos de la Planta/ultraestructura , Hojas de la Planta/fisiología , Hojas de la Planta/ultraestructura , Asteraceae/ultraestructura
14.
An. acad. bras. ciênc ; 89(3): 1565-1578, July-Sept. 2017. tab, graf
Artículo en Inglés | LILACS | ID: biblio-886746

RESUMEN

ABSTRACT This study aims the anatomical description and chemical characterization of aerial parts of Clusia criuva Cambess., Clusiaceae in addition to the evaluation of the antioxidant activity of crude extracts, correlated to the flavonoid content. The morphological characterization was performed using traditional techniques of plant anatomy. For phytochemical studies, crude extracts were obtained by static maceration and analyzed by thin layer chromatography. The antioxidant activity and the flavonoids content were determined by colorimetric methods involving, respectively, 2,2-diphenyl-1-picrylhydrazyl free radical and aluminum chloride. C. criuva has uniseriate epidermis, paracytic stomata, hypostomatic leaves, cuticular flanges and cordiform vascular cylinder with accessory bundles. Chemical prospecting confirmed the abundant presence of terpenes and phenols in the extracts of leaves and of fruits. The methanolic extract of seeds showed the lowest EC50 value, but the methanolic extract of pericarps exhibited the highest maximum antioxidant activity. The results suggested a high percentage of flavonoids in the hexanic extract of pericarps, however, this could represent, in fact, the presence of benzophenones. Secretory ducts and the shape of the midrib are diagnostic for C. criuva. The antioxidant activity is not directly related to the flavonoids. The results indicate the importance of future studies with C. criuva chemical constituents.


Asunto(s)
Extractos Vegetales/química , Clusia/química , Antioxidantes/química , Microscopía Electrónica de Rastreo , Cromatografía en Capa Delgada , Colorimetría , Hojas de la Planta/ultraestructura , Hojas de la Planta/química , Clusia/clasificación , Clusia/ultraestructura , Antioxidantes/aislamiento & purificación
15.
Biol. Res ; 48: 1-8, 2015. ilus, graf
Artículo en Inglés | LILACS | ID: biblio-950797

RESUMEN

BACKGROUND: The epicuticular waxy layer of plant leaves enhances the extreme environmental stress tolerance. However, the relationship between waxy layer and saline tolerance was not established well. The epicuticular waxy layer of rice (Oryza sativa L.) was studied under the NaHCO3 stresses. In addition, strong saline tolerance Puccinellia tenuiflora was chosen for comparative studies. RESULTS: Scanning electron microscope (SEM) images showed that there were significant changes in waxy morphologies of the rice epicuticular surfaces, while no remarkable changes in those of P. tenuiflora epicuticular surfaces. The NaHCO3-induced morphological changes of the rice epicuticular surfaces appeared as enlarged silica cells, swollen corns-shapes and leaked salt columns under high stress. Energy dispersive X-ray (EDX) spectroscopic profiles supported that the changes were caused by significant increment and localization of [Na(+)] and [Cl(-)] in the shoot. Atomic absorption spectra showed that [Na(+)]shoot/[Na(+)]root for P. tenuiflora maintained stable as the saline stress increased, but that for rice increased significantly. CONCLUSION: In rice, NaHCO3 stress induced localization and accumulation of [Na(+)] and [Cl(-)] appeared as the enlarged silica cells (MSC), the swollen corns (S-C), and the leaked columns (C), while no significant changes in P. tenuiflora.


Asunto(s)
Oryza/efectos de los fármacos , Ceras/análisis , Cloruro de Sodio/farmacología , Hojas de la Planta/efectos de los fármacos , Tolerancia a la Sal , Oryza/ultraestructura , Estrés Fisiológico , Microscopía Electrónica de Rastreo , Hojas de la Planta/ultraestructura
16.
Braz. j. biol ; 74(1): 41-51, 2/2014. tab, graf
Artículo en Inglés | LILACS | ID: lil-715593

RESUMEN

We present the leaf anatomy of seven amphibious species of Aeschynomene L. (Papilionoideae, Leguminosae), interpreting their structures and ecological functions, and also, providing information on which their taxonomy can be based, especially of morphologically similar species. We evaluated Aeschynomene americana, A. ciliata, A. evenia, A. denticulata, A. fluminensis, A. rudis and A. sensitiva. The anatomy corroborates the separation of the series Americanae, Fluminenses, Indicae and Sensitivae, with the shape of the petiole, types of trichomes and quantity of vascular units in the petiole as main characteristics to delimit the species. The petiole shape varies from cylindric in A. americana, A. sensitiva and A. fluminensis, to triangular in A. evenia and quadrangular in A. rudis, A. denticulata and A. ciliata. We observed four types of trichomes: hydathode trichome, long conic trichome, short conic trichome and bulb-based trichome. The hydathode trichome was the most common, except for A. americana and A. fluminensis. Species with higher affinity with water share similar adaptive characteristics, including hydathode trichomes described for the first time for the genus. This article adds unseen descriptions for the genus and on the adaptation factors of the amphibious species.


Neste trabalho é apresentada a anatomia foliar de sete espécies anfíbias de Aeschynomene L., interpretando estruturas e suas funções ecológicas e fornecendo informações que subsidiam sua taxonomia, principalmente de espécies semelhantes morfologicamente. Foram avaliadas Aeschynomene americana, A. ciliata, A. evenia, A. denticulata, A. fluminensis, A. rudis e A. sensitiva, pertencentes ao grupo Papilionoideae - Leguminosae. A anatomia corrobora a separação das séries Americanae, Fluminenses, Indicae e Sensitivae, sendo o formato do pecíolo, tipos dos tricomas e quantidade de unidades vasculares no pecíolo as principais características para delimitação das espécies de Aeschynomene. O formato do pecíolo variou de cilíndrico para A. americana, A. sensitiva e A. fluminensis, triangular para A. evenia e quadrangular para A. rudis, A. denticulata e A. ciliata. Foram observados quatro tipos de tricomas, são eles: tricoma-hidatódio, tricoma cônico longo, tricoma de base bulbosa e cônico curto. O tricoma-hidatódio foi o mais comum, ausente somente em A. americana e A. fluminensis. Espécies com maior afinidade pela água compartilham características adaptativas similares, incluindo tricoma-hidatódio descrito pela primeira vez para o gênero. Este trabalho acrescenta descrições inéditas para o gênero e sobre fatores adaptativos das espécies anfíbias.


Asunto(s)
Ecología , Fabaceae/clasificación , Hojas de la Planta/clasificación , Fabaceae/anatomía & histología , Fabaceae/ultraestructura , Microscopía Electrónica de Rastreo , Hojas de la Planta/anatomía & histología , Hojas de la Planta/ultraestructura
17.
Braz. j. microbiol ; 45(3): 977-983, July-Sept. 2014. ilus, tab
Artículo en Inglés | LILACS | ID: lil-727029

RESUMEN

Extraneous DNA interferes with PCR studies of endophytic fungi. A procedure was developed with which to evaluate the removal of extraneous DNA. Wheat (Triticum aestivum) leaves were sprayed with Saccharomyces cerevisiae and then subjected to physical and chemical surface treatments. The fungal ITS1 products were amplified from whole tissue DNA extractions. ANOVA was performed on the DNA bands representing S. cerevisiae on the agarose gel. Band profile comparisons using permutational multivariate ANOVA (PERMANOVA) and non-metric multidimensional scaling (NMDS) were performed on DGGE gel data, and band numbers were compared between treatments. Leaf surfaces were viewed under variable pressure scanning electron microscopy (VPSEM). Yeast band analysis of the agarose gel showed that there was no significant difference in the mean band DNA quantity after physical and chemical treatments, but they both differed significantly (p < 0.05) from the untreated control. PERMANOVA revealed a significant difference between all treatments (p < 0.05). The mean similarity matrix showed that the physical treatment results were more reproducible than those from the chemical treatment results. The NMDS showed that the physical treatment was the most consistent. VPSEM indicated that the physical treatment was the most effective treatment to remove surface microbes and debris. The use of molecular and microscopy methods for the post-treatment detection of yeast inoculated onto wheat leaf surfaces demonstrated the effectiveness of the surface treatment employed, and this can assist researchers in optimizing their surface sterilization techniques in DNA-based fungal endophyte studies.


Asunto(s)
Endófitos/aislamiento & purificación , Técnicas Microbiológicas/métodos , Esterilización/métodos , Triticum/microbiología , Electroforesis en Gel de Gradiente Desnaturalizante , ADN de Hongos/genética , ADN de Hongos/aislamiento & purificación , ADN de Plantas/química , ADN de Plantas/genética , ADN Espaciador Ribosómico/genética , ADN Espaciador Ribosómico/aislamiento & purificación , Microscopía Electrónica de Rastreo , Reacción en Cadena de la Polimerasa , Hojas de la Planta/microbiología , Hojas de la Planta/ultraestructura , Propiedades de Superficie , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/aislamiento & purificación , Saccharomyces cerevisiae/ultraestructura , Triticum/ultraestructura
18.
Rev. biol. trop ; 61(2): 539-546, Jun. 2013. ilus
Artículo en Inglés | LILACS | ID: lil-675449

RESUMEN

The genus Zamia is morphologically and ecologically the most diverse of the order Cycadales. Throughout its history this genus has been restricted to the New World and is presently almost entirely restricted to the Neotropics. Unusual anatomical traits of the leaflets, such as the sunken stomata and thick cuticle, are common in this and related genera. The objective of this research was to study and compare the leaflet anatomy of Zamia acuminata and Z. pseudomonticola and establish possible phylogenetic relationships between the anatomical traits and the near relatives of these species. The leaf material was obtained from living plants and then processed for electron microscopy study. We found that both species are very similar to each other and to Z. fairchildiana, and that they share several unusual traits with other species of the genus, such as the parenchyma morphology, the spatial distribution of tissues between the veins and the stomata morphology. The main differences between these species were seen in their fiber clusters and in the abundance of trichome basal cells on the epidermis. The anatomical similarities between the three species could be the result of their close phylogenetic relationship and the divergences between them could be the result of recent speciation during the Pleistocene, resulting from geological changes in Southern Costa Rica.


Zamia es morfológica y ecológicamente el género más diverso del orden Cycadales. Este género siempre ha estado restringido a América, pero en la actualidad habita principalmente en la región neotropical. Características anatómicas inusuales en los foliolos como los estomas hundidos y las cutículas gruesas son comunes en Zamia y géneros afines. El objetivo de este trabajo consiste en comparar la anatomía de los foliolos de Zamia acuminata y Z. pseudomonticola y establecer posibles relaciones filogenéticas entre las características anatómicas y los parientes cercanos de esta especie. Las hojas de las especies seleccionadas fueron obtenidas de plantas vivas y luego procesadas para el estudio por microscopía electrónica. Ambas especies son muy similares entre sí y respecto a Z. fairchildiana y comparten varias características en común con otras especies del género como son la morfología del parénquima, de los estomas y la distribución espacial de tejidos alrededor de las haces vasculares. Las diferencias más notables entre especies se vieron a nivel de sus paquetes de fibras y en la abundancia de células basales de los tricomas en la epidermis. Las similitudes anatómicas entre estas tres especies pueden ser el resultado de su cercanía filogenética y las diferencias podrían ser el resultado de especiación durante el Pleistoceno, producto de los eventos geológicos y cambios sucedidos en el sur de Costa Rica en esa época.


Asunto(s)
Epidermis de la Planta/ultraestructura , Hojas de la Planta/ultraestructura , Zamiaceae/ultraestructura , Costa Rica , Microscopía Electrónica de Rastreo , Filogenia , Zamiaceae/clasificación
19.
Rev. biol. trop ; 60(3): 1137-1148, Sept. 2012. ilus, tab
Artículo en Inglés | LILACS | ID: lil-659575

RESUMEN

Smilax L. in Brazil is represented by 32 taxa and it is a taxonomically difficult genus because the plants are dioecious and show wide phenotypic variation. The analysis and use of leaf anatomy characters is recognized as a frequently successful taxonomic method to distinguish between individual taxon, when floral material is absent or minute differences in flowers and foliage exist such as in Smilax. The aim of this study was to characterize the anatomical features of the aerial organs in Smilax syphilitica collected from the Atlantic Rainforest, in Santa Teresa-ES and the Smilax aff. syphilitica from the Amazon Rainforest, in Manaus, Brazil. For this, a total of three samples of Smilax were collected per site. Sample leaves and stems were fixed with FAA 50, embedded in historesin, sectioned on a rotary microtome, stained and mounted in synthetic resin. Additionally, histochemical tests were performed and cuticle ornamentation was analyzed with standard scanning electron microscopy. S. syphilitica and S. aff. syphilitica differed in cuticle ornamentation, epidermal cell arrangement and wall thickness, stomata type and orientation, calcium oxalate crystal type, and position of stem thorns. Leaf blades of S. syphilitica from the Amazon Rainforest have a network of rounded ridges on both sides, while in S. aff. syphilitica, these ridges are parallel and the spaces between them are filled with numerous membranous platelets. Viewed from the front, the epidermal cells of S. syphilitica have sinuous walls (even more pronounced in samples from the Amazon); while in S. aff. syphilitica, these cells are also sinuous but elongated in the cross-section of the blade and arranged in parallel. Stomata of S. syphilitica are paracytic, whereas in S. aff. syphilitica, are both paracytic and anisocytic, and their polar axes are directed towards the mid-vein. Calcium oxalate crystals in S. syphilitica are prisms, whereas in S. aff. syphilitica, crystal sand. Thorns occur in nodes and internodes in S. syphilitica but only in internodes in S. aff. syphilitica. These features have proven to be of diagnostic value and may support a separation into two species, but future studies are needed to confirm that S. aff. syphilitica is indeed a new taxon.


Smilax L. en Brasil está representado por 32 táxones y es un género difícil en lo que respecta a su taxonomía porque las plantas son diocas y presentan mucha variación fenotípica. El análisis y uso de los caracteres anatómicos de la hoja es reconocido frecuentemente como un exitoso método taxonómico para distinguir entre los táxones individuales cuando las flores están ausentes o hay diminutas diferencias. El objetivo de este estudio fue caracterizar los rasgos anatómicos de los órganos aéreos en Smilax syphilitica recolectados en el Bosque Atlántico en Santa Teresa- ES y de Smilax aff. syphilitica del Amazonas, Manaus, Brasil. Un total de tres muestras fueron recolectadas por sitio. Las muestras fueron fijadas en FAA 50, sumergidas en historesina, seccionadas en un micrótomo rotatorio, teñidas y montadas en resina sintética. Se hicieron pruebas histoquímicas y la ornamentación de la cutícula fue analizada con microscopía electrónica de barrido estándar. S. syphilitica y difirieron en la ornamentación de la cutícula, la disposición de células epidérmicas y el grosor de la pared, tipo y orientación de estomas, tipo de cristal de oxalato de calcio y la posición de las espinas del tallo. Estas características han probado ser de valor diagnóstico y pueden apoyar la separación de dos especies, pero se necesitan futuros estudios para confirmar que S. S. aff. syphiliticaaff. syphilitica es un nuevo taxon.


Asunto(s)
Epidermis de la Planta/ultraestructura , Hojas de la Planta/ultraestructura , Smilax/clasificación , Microscopía Electrónica de Rastreo , Hojas de la Planta/anatomía & histología , Smilax/anatomía & histología , Smilax/ultraestructura
20.
Bol. latinoam. Caribe plantas med. aromát ; 11(4): 316-330, jul. 2012. ilus, graf
Artículo en Español | LILACS | ID: lil-648049

RESUMEN

Cuphea aquipetala Cav. (Hierba del cancer) is used in Mexican traditional medicine. In the present work, its most frequent medicinal applications were determined through interviews, revision of herbarium specimens, and bibliography. The quoted applications were: to treat pounds and wounds. For these purposes, the drug (leaf and stem) is prepared and administered as infusion, or as poultice. In order to provide data for inclusion of this species in the Herbal Pharmacopoeia of the United Mexican States (FHEUM) we describe its leaf architecture and diagnostic anatomical characters of drug,. The anatomical study revealed that the three types of trichomes observed can aid to differentiate this species from other Cuphea species. Anatomical variation was observed mainly in the midrib of the leaf. Leaf architecture is first described for this species, and provides the basis for future comparisons. In addition, the acetone-water extract of the aerial parts previously reported as cytotoxic activity against DU-145 (human prostate carcinoma) and HCT-15 (human colon carcinoma), showed the presence of polyphenolic compounds of the type of hydrolysable and condensed tannins, mannitol was isolated and identified.


Cuphea aquipetala Cav., Lythraceae (Hierba del cáncer) es utilizada en la medicina tradicional mexicana. En el presente trabajo se determinó mediante entrevistas, consultas de herbario y revisión bibliográfica sus aplicaciones médicas más frecuentes, a saber: para tratar golpes y heridas, para lo cual la droga (hoja y tallo) es preparada en infusión, o administrada en emplastos. Con la finalidad de aportar datos que ayuden a la inclusión de esta especie en la Farmacopea Herbolaria de los Estados Unidos Mexicanos (FHEUM), se describen la arquitectura foliar y los caracteres anatómicos de la droga. El estudio anatómico reveló que los tres tipos de tricomas reconocidos en la especie estudiada apoyan a diferenciarla de otras especies de Cuphea sp. Se observó variación anatómica principalmente en la nervadura central de la hoja. La arquitectura foliar se describe por primera vez para la especie y sienta las bases para futuras comparaciones. Por otra parte, el extracto acetona-agua de las partes aéreas que previamente ha sido reportado con actividad citotóxica contra células DU-145 (carcinoma de próstata humano) y HCT-15 (carcinoma de colon humano) mostró la presencia de compuestos polifenólicos del tipo de los taninos hidrolizables, taninos condensados, y se aisló manitol.


Asunto(s)
Humanos , Cuphea/química , Cuphea/ultraestructura , Etnobotánica , Hojas de la Planta/química , Hojas de la Planta/ultraestructura , Entrevistas como Asunto , Medicina Tradicional , México , Control de Calidad
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