Journal articles on the topic 'Intercellular air space'
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Dami, Imed, and Harrison Hughes. "LEAF ANATOMY OF MICROPROPAGATED GRAPE AFFECTED BY REDUCED WATER POTENTIAL." HortScience 26, no. 6 (June 1991): 725C—725. http://dx.doi.org/10.21273/hortsci.26.6.725c.
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Grape cv. Valiant was micropropagated in an MS medium with and without 2% (W/V) of polyethylene glycol (PEG, MW 8000). Leaf anatomy of control (in vitro, no PEG), treated (in vitro, PEG), field grown and greenhouse grown plants were compared under light microscopy. Cell size, palisade layer formation, relative intercellular air space and apparent chloroplast number varied between the leaves of control and PEG treated (high osmoticum) plantlets. These leaf characteristics in the high osmoticum medium appeared more similar to the leaves of the greenhouse and field grown plants. Leaves from control plantlets contained cells of larger size, lacked normal palisade layer formation, greater intercellular pore spaces and fewer chloroplasts. Leaves of PEG treated plantlets had smaller cells, a more defined palisade layer, reduced intercellular pore spaces and greater number of chloroplasts. Leaves of greenhouse and field grown plants had small cells, a well-defined palisade layer, least intercellular pore space and greatest number of chloroplasts. These results demonstrate that a high osmoticum medium may be used to induce more normal leaf development.
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Slaton, Michèle R., and William K. Smith. "Mesophyll Architecture and Cell Exposure to Intercellular Air Space in Alpine, Desert, and Forest Species." International Journal of Plant Sciences 163, no. 6 (November 2002): 937–48. http://dx.doi.org/10.1086/342517.
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Herrera, Ana. "Are thick leaves, large mesophyll cells and small intercellular air spaces requisites for CAM?" Annals of Botany 125, no. 6 (January 23, 2020): 859–68. http://dx.doi.org/10.1093/aob/mcaa008.
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Abstract Background and Aims It is commonly accepted that the leaf of a crassulacean acid metabolism (CAM) plant is thick, with large mesophyll cells and vacuoles that can accommodate the malic acid produced during the night. The link between mesophyll characteristics and CAM mode, whether obligate or C3/CAM, was evaluated. Methods Published values of the carbon isotopic ratio (δ 13C) as an indicator of CAM, leaf thickness, leaf micrographs and other evidence of CAM operation were used to correlate cell density, cell area, the proportion of intercellular space in the mesophyll (IAS) and the length of cell wall facing the intercellular air spaces (Lmes/A) with CAM mode. Key Results Based on 81 species and relatively unrelated families (15) belonging to nine orders, neither leaf thickness nor mesophyll traits helped explain the degree of CAM expression. A strong correlation was found between leaf thickness and δ 13C in some species of Crassulaceae and between leaf thickness and nocturnal acid accumulation in a few obligate CAM species of Bromeliaceae but, when all 81 species were pooled together, no significant changes with δ 13C were observed in cell density, cell area, IAS or Lmes/A. Conclusions An influence of phylogeny on leaf anatomy was evidenced in a few cases but this precluded generalization for widely separate taxa containing CAM species. The possible relationships between leaf anatomy and CAM mode should be interpreted cautiously.
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Milla-Moreno, Estefania A., Athena D. McKown, Robert D. Guy, and Raju Y. Soolanayakanahally. "Leaf mass per area predicts palisade structural properties linked to mesophyll conductance in balsam poplar (Populus balsamifera L.)." Botany 94, no. 3 (March 2016): 225–39. http://dx.doi.org/10.1139/cjb-2015-0219.
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Modifications to leaf structural components that drive variation in leaf mass per area (LMA) may substantially impact leaf physiology by changing how easily CO2 diffuses through intercellular air space to carboxylation sites in mesophyll tissues. Mesophyll conductance (gm) is inversely proportional to the total pathway length for CO2, including the structural resistances encountered. In balsam poplar (Populus balsamifera L.), gm increases with latitude, paralleled by an increase in LMA. We investigated a family of P. balsamifera (K4×C) with high variation in LMA for different characteristics (tissues, nitrogen content, ultrastructural attributes). We interpreted trait variability using a developmental scale quantified by the leaf plastochron index (LPI). Developmental age significantly affected LMA, but those effects were lost at LPI ≥ 6. We outlined contributions of anatomical components to LMA and found palisade mesophyll properties were the primary drivers of variation in LMA within mature leaves (LPI ≥ 6). Using anatomical data, we derived components corresponding to structural resistances for gm. Perimeters of palisade cells and surface area of palisade exposed to intercellular air space, which may strongly influence CO2 diffusion, were correlated to LMA. Variation in LMA is positively related to differences in structural features expected to increase the conductance to CO2 diffusion within palisade mesophyll.
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Miyazawa, Shin-Ichi, Satomi Yoshimura, Yuki Shinzaki, Masayoshi Maeshima, and Chikahiro Miyake. "Deactivation of aquaporins decreases internal conductance to CO2 diffusion in tobacco leaves grown under long-term drought." Functional Plant Biology 35, no. 7 (2008): 553. http://dx.doi.org/10.1071/fp08117.
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We compared the diffusion conductance to CO2 from the intercellular air space to the chloroplasts (internal conductance (g i)) between tobacco leaves acclimated to long-term drought (drought-acclimated (DA)) and those grown under sufficient irrigation (well-watered (WW)), and analysed the changes in g i in relation to the leaf anatomical characteristics and a possible CO2 transporter, aquaporin. The g i, which was estimated by combined analyses of CO2 gas exchange with chlorophyll fluorescence, in the DA plants was approximately half of that in the WW plants. The mesophyll and chloroplast surface areas exposing the intercellular air space, which potentially affect g i, were not significantly different between the WW and DA plants. The amounts of plasma membrane aquaporins (PIP), immunochemically determined using radish PIP antibodies, were unrelated to g i. After treatment with HgCl2, an aquaporin inhibitor, the water permeability of the leaf tissues (measured as the weight loss of fully-turgid leaf disks without the abaxial epidermis in 1 m sorbitol) in WW plants decreased with an increase in HgCl2 concentration. The g i in the WW plants decreased to similar levels to the DA plants when the detached leaflets were fed with 0.5 mm HgCl2. In contrast, both water permeability and g i were insensitive to HgCl2 treatments in DA plants. These results suggest that deactivation of aquaporins is responsible for the significant reduction in g i observed in plants growing under long-term drought.
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van Rensburg, L., H. Krüger, and G. H. J. Krüger. "Intercellular space variation among air-cured Nicotiana tabacum L. genotypes and its relation to their water use efficiency." South African Journal of Botany 60, no. 4 (August 1994): 227–30. http://dx.doi.org/10.1016/s0254-6299(16)30618-4.
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Lucia, Evan H. De, David Whitehead, and Michael J. Clearwater. "The relative limitation of photosynthesis by mesophyll conductance in co-occurring species in a temperate rainforest dominated by the conifer Dacrydium cupressinum." Functional Plant Biology 30, no. 12 (2003): 1197. http://dx.doi.org/10.1071/fp03141.
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The capacity to conduct CO2 from the intercellar spaces in leaves to the site of fixation (mesophyll conductance, gm) may pose a significant limitation to photosynthesis. Dacrydium cupressinum Sol. ex Lamb. (rimu), a native conifer of New Zealand, and other members of the Podocarpaceae evolved during the Jurassic when the partial pressure of CO2 exceeded 200 Pa. This species has low rates of photosynthesis and high levels of leaf nitrogen, which have led to the hypothesis that low gm restricts photosynthesis. Mesophyll conductance was estimated from gas-exchange and fluorescence measurements for this and other co-occurring tree species [Prumnopitys ferruginea D.�Don (miro), Weinmannia racemosa L.f. (kāmahi), Meterosideros umbellata Cav. (rata)]. Pinus radiata D. Don (radiata pine) and Phaseolus vulgaris L. (bean) were included to provide comparisons with a rapidly growing tree and herbaceous plant with relatively high photosynthetic rates. Mesophyll conductance was not statistically different among indigenous tree species but was lowest for D. cupressinum. This species also had the lowest ratio of mesophyll to stomatal conductance, gm / gst and was the only species where the decline in partial pressure of CO2 was greater from the intercellular air space to the site of fixation (16.3 Pa) than between the bulk air and the intercellular spaces (8.8 Pa), providing support for the hypotheses that low gm limits photosynthesis in this species. As a group, conifers had marginally lower gm and gm / gst ratio than angiosperms, but this difference was strongly influenced by the high values for Phaseolus vulgaris. That co-occurring members of the Podocarpaceae operated differently suggests that low gm may reflect a response to evolutionary pressures other than high atmospheric CO2 partial pressure.
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Lucia, Evan H. De, Michael J. Clearwater, and David Whitehead. "Corrigendum to: The relative limitation of photosynthesis by mesophyll conductance in co-occurring species in a temperate rainforest dominated by the conifer Dacrydium cupressinum." Functional Plant Biology 31, no. 7 (2004): 759. http://dx.doi.org/10.1071/fp03141_co.
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The capacity to conduct CO2 from the intercellar spaces in leaves to the site of fixation (mesophyll conductance, gm) may pose a significant limitation to photosynthesis. Dacrydium cupressinum Sol. ex Lamb. (rimu), a native conifer of New Zealand, and other members of the Podocarpaceae evolved during the Jurassic when the partial pressure of CO2 exceeded 200 Pa. This species has low rates of photosynthesis and high levels of leaf nitrogen, which have led to the hypothesis that low gm restricts photosynthesis. Mesophyll conductance was estimated from gas-exchange and fluorescence measurements for this and other co-occurring tree species [Prumnopitys ferruginea D.�Don (miro), Weinmannia racemosa L.f. (kāmahi), Meterosideros umbellata Cav. (rata)]. Pinus radiata D. Don (radiata pine) and Phaseolus vulgaris L. (bean) were included to provide comparisons with a rapidly growing tree and herbaceous plant with relatively high photosynthetic rates. Mesophyll conductance was not statistically different among indigenous tree species but was lowest for D. cupressinum. This species also had the lowest ratio of mesophyll to stomatal conductance, gm / gst and was the only species where the decline in partial pressure of CO2 was greater from the intercellular air space to the site of fixation (16.3 Pa) than between the bulk air and the intercellular spaces (8.8 Pa), providing support for the hypotheses that low gm limits photosynthesis in this species. As a group, conifers had marginally lower gm and gm / gst ratio than angiosperms, but this difference was strongly influenced by the high values for Phaseolus vulgaris. That co-occurring members of the Podocarpaceae operated differently suggests that low gm may reflect a response to evolutionary pressures other than high atmospheric CO2 partial pressure.
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Pietrasanta, L. I., A. Schaper, and T. M. Jovin. "Imaging subcellular structures of rat mammary carcinoma cells by scanning force microscopy." Journal of Cell Science 107, no. 9 (September 1, 1994): 2427–37. http://dx.doi.org/10.1242/jcs.107.9.2427.
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Scanning force microscopy (SFM) was used for imaging subcellular structures of cultured rat mammary carcinoma cells dried in air. Identification of cellular substructures was achieved by immunofluorescence and specific fluorescence probes. Cells grown attached to a glass support exhibited submicrometer thickness in the dried state. Inside the nuclear domain the nucleoli appeared as prominent conical protrusions. Membrane extensions, microspikes and microvilli were well preserved at the cell periphery after fixation in glutaraldehyde vapor and air-drying and were distinguishable either as isolated elements or intercellular communications. The plasma membrane and soluble proteins were selectively removed with nonionic detergent in a buffer system. The mitochondria were concentrated primarily in the perinuclear space and exhibited a well defined filamentous shape. Their identity was confirmed by specific fluorescence staining with rhodamine 123. In the membrane-free system achieved by dry-cleaving of the sample surface, the cytoskeletal network was resolved as a complex mesh of actin-containing fiber bundles interwoven with a filigree arrangement of thinner filaments. The smallest fibrous substructures revealed by SFM with the scanning tips used to date were approximately 8 to 10 nm in height and 80 nm in width.
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Nelson, Elizabeth A., Tammy L. Sage, and Rowan F. Sage. "Functional leaf anatomy of plants with crassulacean acid metabolism." Functional Plant Biology 32, no. 5 (2005): 409. http://dx.doi.org/10.1071/fp04195.
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Crassulacean acid metabolism (CAM) has evolved independently on dozens of occasions and is now found in over 7% of plant species. In this study, the leaf structure of a phylogenetically diverse assemblage of 18 CAM plants was compared with six C3 plants and four C4 plants to assess whether consistent anatomical patterns that may reflect functional constraints are present. CAM plants exhibited increased cell size and increased leaf and mesophyll thickness relative to C3 and C4 species. CAM species also exhibited reduced intercellular air space (IAS) and reduced length of mesophyll surface exposed to IAS per unit area (Lmes / area). The low volume of IAS and low exposure of mesophyll surface to IAS likely increases internal resistance to CO2 in CAM tissues. While this diffusional barrier may limit uptake of CO2 during Phases II and IV, carbon economy could be enhanced through the reduced loss of internal CO2 during all four phases of CAM.
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Conhaim, R. L., A. Eaton, N. C. Staub, and T. D. Heath. "Equivalent pore estimate for the alveolar-airway barrier in isolated dog lung." Journal of Applied Physiology 64, no. 3 (March 1, 1988): 1134–42. http://dx.doi.org/10.1152/jappl.1988.64.3.1134.
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In high-pressure pulmonary edema, lung interstitial and air space edema liquids have equal protein concentrations (Am. J. Physiol. 231: 1466, 1976). This suggests that the alveolar-airway barrier separating the air and interstitial spaces is relatively unrestrictive, even without apparent epithelial injury. To estimate the equivalent pore population of the alveolar-airway barrier we inflated each of 18 isolated dog lung lobes for 1 h with a solution of colored tracer of uniform radius. Tracer radii ranged from 1.3 to 405 nm. After freezing the lobes in liquid N2, we measured interstitial tracer concentrations in frozen perivascular cuffs or in samples thawed after dissection from frozen cuffs. Relative to the concentrations instilled, interstitial concentrations ranged from 0.34 for the smallest particles (1.3 and 3.5 nm radius) to zero for particles with radii of 405 nm. From the results we designed a pore model of the alveolar-airway barrier to reproduce the concentrations we measured. No single-pore model could be obtained, although a three-pore model fit the data well. The model results predict that pores with radii of 1, 40, and 400 nm would account for 68, 30, and 2% of total liquid flux, respectively. The majority of liquid flux (68%) would occur through passageways smaller than the smallest tracer we used (1.3 nm radius). We believe the alveolar-airway barrier consists not only of tight intercellular junctions that allow passage of only water and electrolytes but also of a smaller number of large leaks that allow passage of particles up to nearly 400 nm in radius.
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Noichinda, Sompoch, Kitti Bodhipadma, and Siwaruth Kong-In. "Capillary Water in Pericarp Enhances Hypoxic Condition during On-Tree Fruit Maturation That Induces Lignification and Triggers Translucent Flesh Disorder in Mangosteen (Garcinia mangostanaL.)." Journal of Food Quality 2017 (2017): 1–7. http://dx.doi.org/10.1155/2017/7428959.
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Translucent flesh of mangosteen normally occurs during fruit ripening. Rainfall, after water stress, enhanced on-tree mature green fruit to develop translucent flesh disorder more frequently. Thus, this research pursued the effect of applied water on translucent flesh disorder development. The on-tree mature green stage fruits were selected and wrapped with 3 layers of fabric sheet. After that, water was continuously dropped (flow rate of 0.6 ml/min) on the wrapped sheet for 0, 1, and 2 days before picking. The results showed that duration time of water applying enhanced the increasing of water absorption significantly in peel. All of water-treated fruits ripened within 2-3 days after harvest and obviously had high lignin in secondary cell wall. It was hypothesized that lignification played an important role in hypoxia defense mechanism since the Na2CO3-SP fractionation extracted from alcohol insoluble residue (AIR) of translucent flesh aril was higher than those of normal aril. This Na2CO3-SP reinforced the strength of cell wall complexity as well as displaying the translucency character. Hence, we concluded that the capillary water (took place in intercellular air space of fruit pericarp) induced hypoxia tolerance mechanism that triggered translucent flesh disorder in mangosteen aril.
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Torre, Sissel, Tove Fjeld, Hans Ragnar Gislerød, and Roar Moe. "Leaf Anatomy and Stomatal Morphology of Greenhouse Roses Grown at Moderate or High Air Humidity." Journal of the American Society for Horticultural Science 128, no. 4 (July 2003): 598–602. http://dx.doi.org/10.21273/jashs.128.4.0598.
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Single node cuttings with one mature leaf were taken from Rosa ×hybrida `Baroness' and rooted in water culture. The plants were subjected to either 90% (high) or 70% (moderate) relative humidity (RH) in climate chambers. Single stem roses with intact roots were transferred to 40% (low) RH to investigate the stomatal response to water stress. Moderate RH plants showed decreasing leaf conductance from day 1 to day 3 during both light and dark phases, in contrast to high RH roses, which showed almost similar leaf conductances during the 3 days. Leaf samples were studied with a light microscope (LM) and a scanning electron microscope (SEM) to quantify morphological and structural changes. Epidermal imprints showed a significantly higher number of stomata and longer stomata, as well as a wider stomatal apertures on roses grown at high RH. The high RH leaves showed a reduced density of vascular tissue and thinner leaves when compared to moderate RH leaves. Enlarged intercellular air-space (ICA) was found due to a reduced number of spongy and palisade mesophyll cells. No obvious difference in shape, size, undulation or the structure of the epicuticular wax was observed in SEM between high and moderate RH grown leaves. In conclusion, roses subjected to high RH showed differences in leaf anatomy, stomatal morphology and stomatal function, which may explain the loss of water control of these plants. Stomatal ontogenesis should occur at RH conditions below 85% to secure roses with a high postharvest quality potential.
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Volz, Richard K., F. Roger Harker, and Sandy Lang. "Firmness Decline in `Gala' Apple during Fruit Development." Journal of the American Society for Horticultural Science 128, no. 6 (November 2003): 797–802. http://dx.doi.org/10.21273/jashs.128.6.0797.
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Puncture force was measured in `Gala'apple [Malus sylvestris (L.) Mill. var. domestica (Borkh.) Mansf.] fruit from 16 to 175 days after full bloom over 2 years using a range of circular flat-tipped probes (1 to 11 mm diameter) to test the firmness of each fruit. The area-dependent (Ka) and perimeter-dependent (Kp) coefficients of puncture force were determined and were used to calculate the indicative puncture force approximating a standard 11.1-mm-diameter Effegi/Magness-Taylor probe for even the smallest fruit. Ka declined exponentially throughout fruit development with much greater changes occurring closer to bloom. In contrast, maximum Kp occurred at 107 to 119 days after full bloom before declining progressively. Estimated firmness (using a 11.1-mm-diameter probe) declined constantly from 16 days after full bloom. Ka was associated with developmental changes in cortical tissue intercellular air space, cell volume and cell packing density although relationships changed throughout fruit growth. However seasonal change in Kp was not associated with any obvious anatomical change in the cortex.
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Sharda, J. N., and R. T. Koide. "Exploring the role of root anatomy in P-mediated control of colonization by arbuscular mycorrhizal fungi." Botany 88, no. 2 (February 2010): 165–73. http://dx.doi.org/10.1139/b09-105.
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Alterations of root anatomy have been largely ignored as potential mechanisms for phosphorus-mediated control of arbuscular mycorrhizal colonization. However, at least three anatomical traits including the proportion of root length with a suberized hypodermis, the distribution of hypodermal passage cells, and the proportion of root volume as intercellular air space may influence the degree of colonization. In the present study, we determined whether these traits could be altered by variation in plant phosphorus (P) status. We grew 15 angiosperm species from 13 families, each at two P availabilities, and determined how P status influenced the three root traits. Of the three traits, only the distribution of passage cells was significantly affected by phosphorus status; high P plants possessed a reduced proportion of root length with passage cells. Therefore, in species with passage cells, change in the proportion of root length with passage cells may represent one mechanism for phosphorus-mediated control of mycorrhizal colonization. However, individual species responses to P treatment varied widely, and no single anatomical mechanism appeared to be responsible for the control of mycorrhizal colonization in all species.
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Haworth, Matthew, Giovanni Marino, and Mauro Centritto. "An introductory guide to gas exchange analysis of photosynthesis and its application to plant phenotyping and precision irrigation to enhance water use efficiency." Journal of Water and Climate Change 9, no. 4 (September 24, 2018): 786–808. http://dx.doi.org/10.2166/wcc.2018.152.
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Abstract Leaf gas exchange is central to the analysis of photosynthetic processes and the development of more productive, water efficient and stress tolerant crops. This has led to a rapid expansion in the use of commercial plant photosynthesis systems which combine infra-red gas analysis and chlorophyll fluorescence (Chl-Flr) capabilities. The present review provides an introduction to the principles, common sources of error, basic measurements and protocols when using these plant photosynthesis systems. We summarise techniques to characterise the physiology of light harvesting, photosynthetic capacity and rates of respiration in the light and dark. The underlying concepts and calculation of mesophyll conductance of CO2 from the intercellular air-space to the carboxylation site within chloroplasts using leaf gas exchange and Chl-Flr are introduced. The analysis of stomatal kinetic responses is also presented, and its significance in terms of stomatal physiological control of photosynthesis that determines plant carbon and water efficiency in response to short-term variations in environmental conditions. These techniques can be utilised in the identification of the irrigation technique most suited to a particular crop, scheduling of water application in precision irrigation, and phenotyping of crops for growth under conditions of drought, temperature extremes, elevated [CO2] or exposure to pollutants.
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Psaras, G. K., G. S. Diamantopoulos, and Chr Makrypoulias P. "CHLOROPLAST ARRANGEMENT ALONG INTERCELLULAR AIR SPACES." Israel Journal of Plant Sciences 44, no. 1 (May 13, 1996): 1–9. http://dx.doi.org/10.1080/07929978.1996.10676627.
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The intracellular distribution of chloroplasts in the mesophyll was studied in leaves taken from seven plant species from different groups: the evergreen sclerophylls Olea europaea and Nerium oleander; the drought semideciduous and seasonally dimorphic shrub Coridothymus capitatus; the winter deciduous Capparis spinosa, which grows entirely during summer; and the cultivated species Hordeum vulgare, Vigna unguiculata, and Citrus aurantium. In all leaves and mesophyll types, chloroplasts were found to line the parts of the walls exposed to the internal leaf atmosphere. The arrangement of the chloroplasts adjacent to intercellular air spaces might be a universal phenomenon facilitating the inward diffusion of CO2.
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Liu, Miao, Xiucheng Liu, Xuhua Du, Helena Korpelainen, Ülo Niinemets, and Chunyang Li. "Anatomical variation of mesophyll conductance due to salt stress in Populus cathayana females and males growing under different inorganic nitrogen sources." Tree Physiology 41, no. 8 (February 8, 2021): 1462–78. http://dx.doi.org/10.1093/treephys/tpab017.
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Abstract Synergistic regulation in leaf architecture and photosynthesis is essential for salt tolerance. However, how plant sex and inorganic nitrogen sources alter salt stress-dependent photosynthesis remains unknown. Leaf anatomical characteristics and photosynthesis of Populus cathayana Rehder females and males were investigated under salt stress conditions combined with nitrate NO3− and ammonium NH4+ supplies to clarify the underlying mechanisms. In salt-stressed females, we observed an increased mesophyll spongy cell density, a reduced chloroplast density, a decreased surface area of chloroplasts adjacent to the intercellular air space (Sc/S) and an increased mesophyll cell area per transverse section width (S/W), consequently causing mesophyll conductance (gm) and photosynthesis inhibition, especially under NH4+ supply. Conversely, males with a greater mesophyll palisade tissue thickness and chloroplast density, but a lower spongy cell density had lower S/W and higher Sc/S, and higher gm and photosynthesis. NH4+-fed females had a lower CO2 conductance through cell wall and stromal conductance perpendicular to the cell wall, but a higher chloroplast conductance from the cell wall (gcyt1) than females supplied with NO3−, whereas males had a higher chloroplast conductance and lower CO2 conductance through cell wall when supplied with NO3− instead of NH4+ under salt stress. These findings indicate sex-specific strategies in coping with salt stress related to leaf anatomy and gm under both types of nitrogen supplies, which may contribute to sex-specific CO2 capture and niche segregation.
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Cereijido, M., R. G. Contreras, L. Shoshani, and I. Larre. "The Na+-K+-ATPase as self-adhesion molecule and hormone receptor." American Journal of Physiology-Cell Physiology 302, no. 3 (February 2012): C473—C481. http://dx.doi.org/10.1152/ajpcell.00083.2011.
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Thanks to the homeostasis of the internal milieu, metazoan cells can enormously simplify their housekeeping efforts and engage instead in differentiation and multiple forms of organization (tissues, organs, systems) that enable them to produce an astonishing diversity of mammals. The stability of the internal milieu despite drastic variations of the external environment (air, fresh or seawater, gastrointestinal fluids, glomerular filtrate, bile) is due to transporting epithelia that can adjust their specific permeability to H2O, H+, Na+, K+, Ca2+, and Cl− over several orders of magnitude and exchange substances with the outer milieu with exquisite precision. This exchange is due to the polarized expression of membrane proteins, among them Na+-K+-ATPase, an oligomeric enzyme that uses chemical energy from ATP molecules to translocate ions across the plasma membrane of epithelial cells. Na+-K+-ATPase presents two types of asymmetries: the arrangement of its subunits, and its expression in one pole of the epithelial cell (“polarity”). In most epithelia, polarity consists of the expression of Na+-K+-ATPase towards the intercellular space and arises in part from the interaction of the extracellular segment of the β-subunit with another β-subunit present in a Na+-K+-ATPase molecule expressed by a neighboring cell. In addition to enabling the Na+-K+-ATPase to transport ions and water vectorially, this position exposes its receptors to ouabain and analogous cardiotonic steroids, which are present in the internal milieu because these were secreted by endocrine cells.
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Hossain, M. M., and H. Nonami. "Effect of salt stress on physiological response of tomato fruit grown in hydroponic culture system." Horticultural Science 39, No. 1 (February 16, 2012): 26–32. http://dx.doi.org/10.17221/63/2011-hortsci.
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The effect of salt stress on physiological response of hydroponically grown tomato fruit was investigated. Fruit growth rate, water status, cuticle permeability and induction of blossom-end rot (BER) of tomato fruit were considered for this study. Salt stress was applied by using Ca salt treatment and it plays an important role on all parameters studied in this experiment. Fruit growth rate, predawn water potential, osmotic potential and cuticle permeability were significantly lower in treated plants than in control plants. On the other hand, tissue turgor of control and treated fruit showed almost similar values 12 days after flowering (DAF). This result indicated that turgor was osmotically regulated in fruit under stress condition. Fruit growth rate was found to decline from 12 DAF and eventually ceased when BER externally appeared on fruit surface at the age of 19 DAF in this experiment. The reduction of growth rate coincided with the reduction of water potential in fruit tissue due to salt stress. Although BER externally appeared at 19 DAF anatomical investigation showed that intercellular air space becomes discoloured at least one week before external symptoms appeared on fruit tip. Different levels of cuticular permeability indicated that the deposition of cuticular wax on fruit surface was enhanced by the salt stress condition in tomato fruit. Since, BER was found to appear on fruit tip under high calcium concentration in solution it can be concluded that calcium deficiency was not the only the cause of BER in tomato, rather salt stress might alter metabolic activity in developing tomato fruit.
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Evans, Michael J., Michelle V. Fanucchi, Gregory L. Baker, Laura S. Van Winkle, Lorraine M. Pantle, Susan J. Nishio, Edward S. Schelegle, et al. "Atypical development of the tracheal basement membrane zone of infant rhesus monkeys exposed to ozone and allergen." American Journal of Physiology-Lung Cellular and Molecular Physiology 285, no. 4 (October 2003): L931—L939. http://dx.doi.org/10.1152/ajplung.00175.2003.
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Development of the basement membrane zone (BMZ) occurs postnatally in the rhesus monkey. The purpose of this study was to determine whether house dust mite allergen (HDMA) plus ozone altered this process. Rhesus monkeys were exposed to a regimen of HDMA and/or ozone or filtered air for 6 mo. To detect structural changes in the BMZ, we measured immunoreactivity of collagen I. To detect functional changes in the BMZ, we measured perlecan and fibroblast growth factor-2 (FGF-2). We also measured components of the FGF-2 ternary signaling complex [fibroblast growth factor receptor-1 (FGFR-1) and syndecan-4]. The width of the BMZ was irregular in the ozone groups, suggesting atypical development of the BMZ. Perlecan was also absent from the BMZ. In the absence of perlecan, FGF-2 was not bound to the BMZ. However, FGF-2 immunoreactivity was present in basal cells, the lateral intercellular space (LIS), and attenuated fibroblasts. FGFR-1 immunoreactivity was downregulated, and syndecan-4 immunoreactivity was upregulated in the basal cells. This suggests that FGF-2 in basal cells and LIS may be bound to the syndecan-4. We conclude that ozone and HDMA plus ozone effected incorporation of perlecan into the BMZ, resulting in atypical development of the BMZ. These changes are associated with specific alterations in the regulation of FGF-2, FGFR-1, and syndecan-4 in the airway epithelial-mesenchymal trophic unit, which may be associated with the developmental problems of lungs associated with exposure to ozone.
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Mizuki, Inoue, Yoshiharu Sango, Kiyoshi Ishida, Yuko T. Hanba, Masaaki Chiwa, Yoshitoshi Uehara, and Atsushi Kume. "Effects of sex and soil water chemistry on leaf morphology and physiology of Myrica gale var. tomentosa." PLOS ONE 17, no. 9 (September 22, 2022): e0275024. http://dx.doi.org/10.1371/journal.pone.0275024.
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Plants respond to environmental stressors, such as an oligotrophic environments, by altering the morphological and physiological functions of their leaves. Sex affects these functions because of the asymmetric cost of reproduction in dioecious plants. We compared the leaf mass per leaf area (LMA), ratio of intercellular air space in leaf mesophyll tissue (mesophyll porosity), palisade thickness, and carbon isotope ratio (δ13C) of leaves of the dioecious shrub Myrica gale based on sex and gradients of soil water chemistry across habitats in the field. The PCA showed that the first three principal components accounted for 84.5% of the variation. PC1 to PC3 were associated with the origin of soil water, nitrogen status of habitats, and sea–salt contributions, respectively. LMA varied from 5.22 to 7.13 μg/cm2, and it was positively related to PC2 and negatively related to PC3, but not to PC1 or sex, suggesting that LMA was low under poor nitrogen conditions and varied with salinity. Mesophyll porosity values were over 50% for all habitats. Mesophyll porosity was positively affected by PC3 and smaller in females than in males. This suggests that M. gale exhibits differences in mesophyll anatomy according to sex. Palisade thickness ranged from 0.466 to 0.559 mm/mm. The leaves of females had thinner palisade layers per mesophyll layer than those of males; however, the habitat did not affect the thickness of the palisade layer per mesophyll layer. The δ13C values of leaves varied from −32.14 to −30.51 ‰. We found that δ13C values were positively related to PC2 but not to PC1, PC3, and sex. Under poor nitrogen conditions, the δ13C of M. gale leaves decreased, suggesting that nutrient deficiency would decrease more under the long-term averaged ratio of photosynthesis than stomatal conductance, leading to low water use efficiency.
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Taluta, Hesty Ester, Hanny L. Rampe, and Marhaenus J. Rumondor. "Pengukuran Panjang dan Lebar Pori Stomata Daun Beberapa Varietas Tanaman Kacang Tanah (Arachis hypogaea L.)." Jurnal MIPA 6, no. 2 (August 8, 2017): 1. http://dx.doi.org/10.35799/jm.6.2.2017.16835.
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Kacang tanah (Arachis hypogaea L.) merupakan salah satu tanaman pangan bernilai ekonomi tinggi, dan sebagai tanaman kacang-kacangan terpenting kedua setelah kedelai.Pori stomata merupakan tempat terjadinya pertukaran gas dan air antara atmosfer dengan sistem ruang antar sel yang berada pada jaringan mesofil di bawah epidermis.Setiap varietas tanaman kacang tanah memiliki respon terhadap faktor lingkungan yang berbeda seperti ketahanan terhadap cekaman fisilogis termasuk kemampuan membuka dan menutupnya stomata.Penelitian ini bertujuan untuk mengukur panjang dan lebar pori stomata daun beberapa varietas kacang tanah (Arachis hypogaeaL.). Penelitian dilaksanakan di rumah plastikFakultas MIPA Unsrat selama 30 hari. Hasil penelitian menunjukkan bahwa keempat varietas memiliki panjang dan lebar stomata yang lebih panjang adalah varietas Gajah 81,80 ± 28,72 µm, varietas Lokal 79,81 ± 24,85 µm, varietas Jerapah 69,28 ± 22,60 µm dan varietas Kelinci 57,22 ± 25,02 µm. Lebar pori stomata yang membuka lebih besar adalah varietas Lokal 31,13 ± 9,77 µm, varietas Gajah 29,22 ± 3,71 µm, varietas Jerapah 27,72 ± 11,65 µm dan varietas Kelinci 21,32 ± 12,78 µm.Peanut are one of the high value food plants and as the second highest bean crop after soybeans. The Pore of Stomata plays was a place of gas and water exchange between the atmosphere and the intercellular space located in the mesophyll tissue beneath the epidermis. Each variety of peanut crops has responses to different environmental factors such as resistance to physical stress, including the ability to open and close the stomata. This study aims to measure the length and width of stomata pores of several peanut varieties (Arachis hypogaea L.). The research was conducted in plastic house of Faculty of Mathematics and Natural Sciences Unsrat for 30 days. The results showed that the four varieties had length and stomatal length 81,80 ± 28,72 μm, followed by local varieties 79,81 ± 24,85 μm, giraffe varieties 69,28 ± 22,60 μm and 57,22 ± rabbit varieties 25.02 μm. Stomatal pore 31.13 ± 9.77 μm, followed by elephant varieties 29.22 ± 3.71 μm, giraffe varieties 27.72 ± 11.65 μm and rabbit varieties 21.32 ± 12.78 μm.
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Joseph, Dilip, Omar Tirmizi, Xiao-Ling Zhang, Edward D. Crandall, and Richard L. Lubman. "Polarity of alveolar epithelial cell acid-base permeability." American Journal of Physiology-Lung Cellular and Molecular Physiology 282, no. 4 (April 1, 2002): L675—L683. http://dx.doi.org/10.1152/ajplung.00330.2001.
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We investigated acid-base permeability properties of electrically resistive monolayers of alveolar epithelial cells (AEC) grown in primary culture. AEC monolayers were grown on tissue culture-treated polycarbonate filters. Filters were mounted in a partitioned cuvette containing two fluid compartments (apical and basolateral) separated by the adherent monolayer, cells were loaded with the pH-sensitive dye 2′,7′-bis(2-carboxyethyl)-5(6)-carboxyfluorescein, and intracellular pH was determined. Monolayers in HCO[Formula: see text]-free Na+ buffer (140 mM Na+, 6 mM HEPES, pH 7.4) maintained a transepithelial pH gradient between the two fluid compartments over 30 min. Replacement of apical fluid by acidic (6.4) or basic (8.0) buffer resulted in minimal changes in intracellular pH. Replacement of basolateral fluid by acidic or basic buffer resulted in transmembrane proton fluxes and intracellular acidification or alkalinization. Intracellular alkalinization was blocked ≥80% by 100 μM dimethylamiloride, an inhibitor of Na+/H+exchange, whereas acidification was not affected by a series of acid/base transport inhibitors. Additional experiments in which AEC monolayers were grown in the presence of acidic (6.4) or basic (8.0) medium revealed differential effects on bioelectric properties depending on whether extracellular pH was altered in apical or basolateral fluid compartments bathing the cells. Acid exposure reduced (and base exposure increased) short-circuit current from the basolateral side; apical exposure did not affect short-circuit current in either case. We conclude that AEC monolayers are relatively impermeable to transepithelial acid/base fluxes, primarily because of impermeability of intercellular junctions and of the apical, rather than basolateral, cell membrane. The principal basolateral acid exit pathway observed under these experimental conditions is Na+/H+ exchange, whereas proton uptake into cells occurs across the basolateral cell membrane by a different, undetermined mechanism. These results are consistent with the ability of the alveolar epithelium to maintain an apical-to-basolateral (air space-to-blood) pH gradient in situ.
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Laisk, Agu, Olevi Kull, and Heino Moldau. "Ozone Concentration in Leaf Intercellular Air Spaces Is Close to Zero." Plant Physiology 90, no. 3 (July 1, 1989): 1163–67. http://dx.doi.org/10.1104/pp.90.3.1163.
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Schott, Rena T., Christoph Neinhuis, and Anita Roth‐Nebelsick. "Extracellular ice formation in special intercellular air spaces in Stachys byzantina C. Koch." Feddes Repertorium 131, no. 4 (October 14, 2020): 233–43. http://dx.doi.org/10.1002/fedr.202000014.
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Bondada, B. R., R. Romero-Aranda, J. Syvertsen, and L. Albrigo. "Cytological Modifications of Phytotoxicity Induced by Foliar-applied Urea-nitrogen in Citrus." HortScience 30, no. 4 (July 1995): 879E—879. http://dx.doi.org/10.21273/hortsci.30.4.879e.
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Foliar applications of urea-nitrogen are widely used to alleviate N deficiencies in citrus; however, improper applications can cause serious foliar burn and loss of active green leaf area. Light (LM), transmission (TEM), and scanning (SEM) electron microscopy were used to characterize anatomical and ultrastructural details of foliar burn in citrus. LM examination of the burned leaf area showed collapsed adaxial and abaxial epidermal cells and plasmolysis of mesophyll cells that created large intercellular spaces. SEM showed wrinkling of both the adaxial and abaxial epidermal cells. TEM revealed cytoplasmic vacuolation, disruption of cellular membrane, degradation of grana, and appearance of large plastoglobuli, implying loss of physiological activity. In contrast, control leaves had turgid adaxial and abaxial epidermal cells and compact mesophyll cells with few intercellular air spaces.
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Showalter, Robert K. "Postharvest Water Intake and Decay of Tomatoes." HortTechnology 3, no. 1 (January 1993): 97–98. http://dx.doi.org/10.21273/horttech.3.1.97.
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Serious, postharvest decay losses occurred in tomatoes when water in which they were submerged was cooler than the fruit. Tomatoes have extensive intercellular air spaces, a heavily cutinized epidermis, and no stomatal openings. When tomatoes with unbroken skins were submerged in packinghouse dump tank water of lower temperatures, the internal air contracted and water plus decay organisms were drawn into the fruits through the stem scar. Heating dump tank water has been successful in limiting this decay problem.
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Karabourniotis, George, Nikos Papastergiou, Eleni Kabanopoulou, and Costas Fasseas. "Foliar sclereids of Olea europaea may function as optical fibres." Canadian Journal of Botany 72, no. 3 (March 1, 1994): 330–36. http://dx.doi.org/10.1139/b94-043.
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Adaxial epidermises that contained an intact "subepidermal" "T"-shaped sclereid network, were isolated from olive tree leaves using a new method of enzymatic maceration. In the leaf, the sclereid network was anchored on the adaxial epidermis. The basal parts of the T-shaped sclereids penetrate the palisade cell layers into the underlying spongy parenchyma cells. In paradermal sections, the basal parts of the sclereids appeared as light-emitting sources or spots among the dark-green background of the palisade layers. The light spots almost disappeared when the intercellular air spaces were filled with immersion oil that had a similar refractive index to that of cell walls. It is plausible that light is propagated through multiple reflections between the thick cell wall of sclereids and the air filling the intercellular spaces, the former having a significantly higher refractive index. Sclereids act like synthetic optical fibres and, besides other functions, they may contribute to the improvement of the light microenvironment within the mesophyll of the thick and compact sclerophyllous leaves of Olea. Key words: foliar sclereids, optical fibres, light guiding, Olea europaea.
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Moldau, Heino, and Irina Bichele. "Plasmalemma protection by the apoplast as assessed from above-zero ozone concentrations in leaf intercellular air spaces." Planta 214, no. 3 (November 21, 2001): 484–87. http://dx.doi.org/10.1007/s00425-001-0678-0.
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Ehrenberger*, Jennifer A., and Adelheid R. Kuehnle. "Enhanced Histological Technique for Observation of Spathe Pigmentation in Anthurium species and Hybrids." HortScience 39, no. 4 (July 2004): 865D—865. http://dx.doi.org/10.21273/hortsci.39.4.865d.
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A hybridization strategy for certain coloration could be developed based on accurate histological information of parental material together with the knowledge of heritability of color and color intensity. A sample of 12 Anthurium species and hybrids were histologically examined for pigmentation in spathes using a new method employing vacuum infiltration of spathe tissue with polyethylene glycol (PEG) prior to cross-sectioning. PEG infiltration displaces intercellular air spaces between cells. This method greatly improved the clarity of the cross sections and consequently improved observations of spatial localization of anthocyanins and chloroplasts. This infiltration method accurately identified the spatial localization of pigments for future breeding reference, notably among Anthurium species.
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Huang, C. X., L. E. C. Ling, M. E. McCully, and M. J. Canny. "Cryo analytical microscopy: Multiple applications for plant structure and physiology." Proceedings, annual meeting, Electron Microscopy Society of America 54 (August 11, 1996): 76–77. http://dx.doi.org/10.1017/s0424820100162843.
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Carleton University’s cyo-analytical SEM facility deals with a very wide range of specimens from all the sciences. One of its major specializations is the study of plant structure and function, as illustrated by reference to particular research programs, for example: Stabilization of structures that cannot be preserved by conventional fixation and embedding methods. Many plant tissues are constructed of extremely fragile cell walls containing large vacuoles with high turgor pressures within, interspersed with large volumes of air or fluid. Plants which grow under water are a conspicuous example, requiring large internal open channels for the transport of gases to and from the roots. Other fragile tissues and those having cell walls that are impermeable to solvents and resins have been preserved in roots of desert monocotyledons, and in tree roots. Fluids in spaces between cells. We have pioneered the discovery that many intercellular spaces in plant tissues, always believed to contain air, are in fact filled with fluid. These spaces in sugarcane stems (Figs. 1 & 2) have been shown to contain both strong sugar solution, and an endophyte that lives on this sugar and fixes atmospheric nitrogen. The large air spaces (aerenchyma) in some roots, always considered an aeration system, have been shown to contain water some of the time, and to enhance diffusion of solutes in roots. We have also discovered that roots, always considered to be organs for collecting water from soil, also excrete water to the soil at night. Distribution of nutrient ions in plant tissues. Quantitative analysis of nutrient ions (especially potassium) in individual cells of roots, stems and leaves are opening up new perspectives on the acquisition, use and transport of ions in plants. Bubbles of air and water.
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Kano, Yasutaka. "Relationship between the Occurrence of Hollowing in Watermelon and the Size and the Number of Fruit Cells and Intercellular Air Spaces." Engei Gakkai zasshi 62, no. 1 (1993): 103–12. http://dx.doi.org/10.2503/jjshs.62.103.
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Sibbernsen, Erik, and Keith A. Mott. "Stomatal Responses to Flooding of the Intercellular Air Spaces Suggest a Vapor-Phase Signal Between the Mesophyll and the Guard Cells." Plant Physiology 153, no. 3 (May 14, 2010): 1435–42. http://dx.doi.org/10.1104/pp.110.157685.
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Xiang, Jiqian, Jiajia Ming, Hongqing Yin, Yunfen Zhu, Yajie Li, Lan Long, Ziyun Ye, et al. "Anatomy and Histochemistry of the Roots and Shoots in the Aquatic Selenium Hyperaccumulator Cardamine hupingshanensis (Brassicaceae)." Open Life Sciences 14, no. 1 (July 23, 2019): 318–26. http://dx.doi.org/10.1515/biol-2019-0035.
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AbstractThe perennial selenium (Se) hyperaccumulator Cardamine hupingshanensis (Brassicaceae) thrives in aquatic and subaquatic Se-rich environments along the Wuling Mountains, China. Using bright-field and epifluorescence microscopy, the present study determined the anatomical structures and histochemical features that allow this species to survive in Se-rich aquatic environments. The roots of C. hupingshanensis have an endodermis with Casparian walls, suberin lamellae, and lignified secondary cell walls; the cortex and hypodermal walls have phi (Φ) thickenings; and the mature taproots have a secondary structure with a periderm. The stems possess a lignified sclerenchymal ring and an endodermis, and the pith and cortex walls have polysaccharide-rich collenchyma. Air spaces are present in the intercellular spaces and aerenchyma in the cortex and pith of the roots and shoots. The dense fine roots with lignified Φ thickenings and polysaccharide-rich collenchyma in the shoots may allow C. hupingshanensis to hyperaccumulate Se. Overall, our study elucidated the anatomical features that permit C. hupingshanensis to thrive in Se-rich aquatic environments.
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Scartazza, A., M. Lauteri, M. C. Guido, and E. Brugnoli. "Carbon isotope discrimination in leaf and stem sugars, water-use efficiency and mesophyll conductance during different developmental stages in rice subjected to drought." Functional Plant Biology 25, no. 4 (1998): 489. http://dx.doi.org/10.1071/pp98017.
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Carbon isotope discrimination (Δ), growth analysis, water-use efficiency (WUE) and gas exchange characteristics were studied in rice plants (Oryza sativa L.) subjected to drought during different developmental stages. Drought caused major effects on growth, WUE, Δ and photosynthetic CO2 assimilation. Substantial differences in the Δ of the bulk biomass among different organs and in carbohydrates extracted from leaves and stems were observed. Possible influences of chemical composition, fractionation during translocation and seasonal changes in the ratio of intercellular and atmospheric partial pressures of CO2 on such differences in Δ are discussed. Stem carbohydrate Δ was correlated with relative growth rate, and, during early grain filling, was negatively correlated with WUE measured between flowering and early grain filling. Δ in leaf sugars was used to estimate mesophyll conductance (gm), the conductance to CO2 diffusion inside leaves, from the intercellular air spaces to the chloroplast. During ontogeny, gm showed a marked progressive decrease, evident in both droughted plants and fully irrigated controls. There was a positive correlation between the rate of CO2 assimilation and gm. The analysis of Δ in leaf and stem carbohydrates is proposed as a useful indicator of growth, WUE and photosynthetic parameters relevant for yield of rice under drought-prone conditions.
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Pathare, Varsha S., Nuria Koteyeva, and Asaph B. Cousins. "Increased adaxial stomatal density is associated with greater mesophyll surface area exposed to intercellular air spaces and mesophyll conductance in diverse C 4 grasses." New Phytologist 225, no. 1 (September 4, 2019): 169–82. http://dx.doi.org/10.1111/nph.16106.
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Silvester, Warwick B., Birgit Langenstein, and R. Howard Berg. "Do mitochondria provide the oxygen diffusion barrier in root nodules of Coriaria and Datisca?" Canadian Journal of Botany 77, no. 9 (December 18, 1999): 1358–66. http://dx.doi.org/10.1139/b99-062.
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Root nodules of Coriaria Lindsay and Datisca Baill. display a unique anatomy in which the symbiotic vesicles radiate inwards towards a central vacuole. Use of the confocal microscope and the redox dye cyano-tetrazolium chloride demonstrates that the vesicles are the sites of reducing potential and that there is a sharp cut-off in reducing potential at the base of the vesicles. The use of the lipophylic cationic dye rhodamine 123 revealed a continuous blanket of mitochondria in this zone. This was verified by transmission electron microscope views of nodule cells. Further studies reveal that the mitochondrial layer also forms a discontinuous layer around the intercellular air spaces. The nodules of plants grown with root systems at 5 and 40 kPa O2 did not show any differences in the thickness of the mitochondrial layer. Microtubules are also radially arranged in these cells and mitochondria are likely to reach their position by moving along this radial framework.Key words: actinorhiza, mitochondria, nitrogen fixation, nitrogenase, nodule, oxygen protection.
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Crang, R. E., M. Mueller, and K. Zierold. "Cryosectioning plant roots prepared by high-pressure freezing." Proceedings, annual meeting, Electron Microscopy Society of America 45 (August 1987): 662–63. http://dx.doi.org/10.1017/s0424820100127748.
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Obtaining frozen-hydrated sections of plant tissues for electron microscopy and microanalysis has been considered difficult, if not impossible, due primarily to the considerable depth of effective freezing in the tissues which would be required. The greatest depth of vitreous freezing is generally considered to be only 15-20 μm in animal specimens. Plant cells are often much larger in diameter and, if several cells are required to be intact, ice crystal damage can be expected to be so severe as to prevent successful cryoultramicrotomy. The very nature of cell walls, intercellular air spaces, irregular topography, and large vacuoles often make it impractical to use immersion, metal-mirror, or jet freezing techniques for botanical material.However, it has been proposed that high-pressure freezing (HPF) may offer an alternative to the more conventional freezing techniques, inasmuch as non-cryoprotected specimens may be frozen in a vitreous, or near-vitreous state, to a radial depth of at least 0.5 mm.
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JIANU, Loreley D., Rodica BERCU, and Dan R. POPOVICIU. "Silene thymifolia Sibth. et Sm. (Caryophyllaceae) – A vulnerable species in Romania: Anatomical aspects of vegetative organs." Notulae Scientia Biologicae 13, no. 1 (March 3, 2021): 10875. http://dx.doi.org/10.15835/nsb13110875.
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Silene thymifolia (Caryophyllaceae) is considered a rare, near-threatened species in Romania, growing only on Black Sea coastal dunes. Anatomical aspects of the root, stem and leaf of this species are presented in this study. Root, stem and leaves were analysed by brightfield microscopy, with specific staining. The root in cross section exhibited a secondary structure, generated by the activity of phellogen, and vascular cambium, with thick cork, continuous secondary xylem rings. no pith rays, but with cortical air lacunes. The stem had a primary structure with a number of collateral vascular bundles arranged on a single circle, with thick cortical schlerenchymal layers and oxalate crystals in pith cells. The epidermis showed stomata and glandular hairs. The leaf was amphystomatic leaf, with a heterogeneous mesophyll (equifacial type) and embedded vascular bundles, with a rounded mid rib surrounded by a parenchyma sheath. The spongy tissue has some large intercellular air spaces with druses. The mechanical tissue is well developed in the root and stem and poorly developed, represented by few collenchyma elements in the mesophyll, being represented by a continuous schlerenchyma fibers band present in root and stem and collenchyma in the leaf. The secretory histological elements were represented by epidermal glandular hairs and oxaliferous cells (druses) present in stem and leaf.
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Apostolakos, P., and B. Galatis. "Studies on the development of the air pores and air chambers of Marchanda paleacea. II. Ultrastructure of the initial aperture formation with particular reference to cortical microtubule organizing centres." Canadian Journal of Botany 63, no. 4 (April 1, 1985): 744–56. http://dx.doi.org/10.1139/b85-094.
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The initiation of the intercellular spaces (ISs) of the initial apertures (IAs) follows the formation of surface cavities (SCs). The latter represent slight deepenings in the external periclinal walls of particular superficial thallus cells at the regions where their anticlinal walls meet one another. This event keeps pace with the deposition of wall pads at the wall junctions below the SC. Afterwards, the thickened wall areas are detached and thus the IS is initiated. By an inward development the IS reaches the subprotodermal layer. This is carried out by the coordination of three gradual processes: the inward spreading of the local wall thickening and the following detachment and expansion of the thickened regions. The findings favour the conclusion that the opening of the IS is the outcome of a highly controlled morphogenetic process. The interphase IA cells possess a well-organized cortical microtubule (MT) cytoskeleton, particularly at the area where the IS opens. In these regions, sets of anticlinal and periclinal MTs appear. During the SC stage the anticlinal MTs dominate, while during IS formation, the periclinal ones are most abundant. The above MTs, as well as other ones entering deeper in the cytoplasm, initially converge on the cortical cytoplasm adjacent to the SC and later on the region surrounding the lower part of the growing IS, where vesicles and endoplasmic reticulum are gathered. The observations suggest the continuous function of cortical MT organizing centres in the cytoplasm and (or) the adjoining plasmalemma, initially underneath the SC and later below the lower part of the growing IS, where local wall thickenings are deposited.
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Yu, Gordon H., Martha J. Sack, Zubair W. Baloch, Denise V. S. DeFrias, and Prabodh K. Gupta. "Occurrence of intercellular spaces (windows) in metastatic adenocarcinoma in serous fluids: A cytomorphologic, histochemical, and ultrastructural study." Diagnostic Cytopathology 20, no. 3 (March 1999): 115–19. http://dx.doi.org/10.1002/(sici)1097-0339(199903)20:3<115::aid-dc1>3.0.co;2-3.
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Vyas, Poonam, Madho Singh Bisht, Shin-Ichi Miyazawa, Satoshi Yano, Ko Noguchi, Ichiro Terashima, and Sachiko Funayama-Noguchi. "Effects of polyploidy on photosynthetic properties and anatomy in leaves of Phlox drummondii." Functional Plant Biology 34, no. 8 (2007): 673. http://dx.doi.org/10.1071/fp07020.
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Polyploidy affects photosynthesis by causing changes in morphology, anatomy and biochemistry. However, in newly developed polyploids, the genome may be unstable. In this study, diploid (2×) and synthetic autotetraploids in initial (4×-C0) and 11th generations (4×-C11) of Phlox drummondii Hook were used to study the effects of chromosome doubling and genome stabilisation on leaf photosynthesis and anatomical properties. The light-saturated photosynthetic rate on a leaf area basis at 360 µmol CO2 mol–1 air (A360) was highest in 4×-C11 leaves, intermediate in 4×-C0 leaves, and lowest in 2× leaves. Rubisco amounts, CO2-saturated photosynthetic rate at 1200 µmol CO2 mol–1 air at PPFD of 1000 µmol m–2 s–1 (A1200, representing the capacity for RuBP regeneration), cumulative surface areas of chloroplasts facing intercellular spaces (Sc), all expressed on a leaf area basis, were all higher in 4× leaves than in 2× leaves, and stomatal conductance (gs) at 360 µmol CO2 mol–1 air was only higher in the 4×-C11 leaves. A360 for the 4×-C11 leaves was greater than that in the 4×-C0 leaves despite having similar amounts of Rubisco. This was presumably associated with a greater RuBP regeneration capacity, as well as an increase in Sc and gs, which would increase the CO2 concentration of Rubisco. These results indicate that the higher rate of photosynthesis in 4×-C11 leaves was not an immediate outcome of chromosome doubling; rather, it was due to adjustment and adaptation during the process of genome stabilisation.
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Ye, Miao, Zhengcan Zhang, Guanjun Huang, and Yong Li. "Leaf Photosynthesis and Its Temperature Response Are Different between Growth Stages and N Supplies in Rice Plants." International Journal of Molecular Sciences 23, no. 7 (March 31, 2022): 3885. http://dx.doi.org/10.3390/ijms23073885.
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Leaf photosynthesis is highly correlated with CO2-diffusion capacities, which are determined by both leaf anatomical traits and environmental stimuli. In the present study, leaf photosynthetic rate (A), stomatal conductance (gs), mesophyll conductance (gm) and the related leaf anatomical traits were studied on rice plants at two growth stages and with two different N supplies, and the response of photosynthesis to temperature (T) was also studied. We found that gm was significantly higher at mid-tillering stage and at high N treatment. The larger gm was related to a larger chloroplast surface area facing intercellular air spaces and a thinner cell wall in comparison with booting stage and zero N treatment. At mid-tillering stage and at high N treatment, gm showed a stronger temperature response. The modelling of the gm-T relationships suggested that, in comparison with booting stage and zero N treatment, the stronger temperature response of gm was related to the higher activation energy of the membrane at mid-tillering stage and at high N treatment. The findings in the present study can enhance our knowledge on the physiological and environmental determinants of photosynthesis.
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Villányi, Vanda, Helga Déri, Evelin Péli, and Zsolt Csintalan. "Differences in histological and physiological traits of ozone sensitive and resistant bean strains." Open Life Sciences 8, no. 4 (April 1, 2013): 386–97. http://dx.doi.org/10.2478/s11535-013-0140-2.
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AbstractAn examination of possible histological causes of differences in ozone sensitivity between ozone sensitive (R123) and resistant (S156) Phaseolus vulgaris strains was carried out. A distinction between the causes and effects of ozone sensitivity was also performed. We studied several morphological and histological traits, which included stomata number and size and also looked at different cell characteristics, such as stomatal index; leaf tissue thickness, fraction and gaseous conductance of intercellular air spaces. Together with this, we made gas-exchange measurements and found inner CO2 levels to be higher in the ozone sensitive strain. We also found several quantitative morphological parameters between the two strains to be initially different, however, these differences changed after exposure to summer climate and ozone. Stomatal function between the two strains was also differently altered by the pollutant, which was apparent from differences in stomatal openness when investigated in summer. According to our histological data, epidermal cells of the ozone sensitive strain grew larger on leaves that developed after exposure to cumulative considerable phytotoxic ozone doses; moderately decreasing the number of stomata and epidermal cells per mm2 epidermal area despite the originally higher number of epidermal cells in sensitive plants. Cross sections of injured sensitive leaves revealed disorganisation of mesophyllum tissues.
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Stegner, Matthias, Barbara Lackner, Tanja Schäfernolte, Othmar Buchner, Nannan Xiao, Notburga Gierlinger, Andreas Holzinger, and Gilbert Neuner. "Winter Nights during Summer Time: Stress Physiological Response to Ice and the Facilitation of Freezing Cytorrhysis by Elastic Cell Wall Components in the Leaves of a Nival Species." International Journal of Molecular Sciences 21, no. 19 (September 24, 2020): 7042. http://dx.doi.org/10.3390/ijms21197042.
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Ranunculus glacialis grows and reproduces successfully, although the snow-free time period is short (2–3 months) and night frosts are frequent. At a nival site (3185 m a.s.l.), we disentangled the interplay between the atmospheric temperature, leaf temperatures, and leaf freezing frequency to assess the actual strain. For a comprehensive understanding, the freezing behavior from the whole plant to the leaf and cellular level and its physiological after-effects as well as cell wall chemistry were studied. The atmospheric temperatures did not mirror the leaf temperatures, which could be 9.3 °C lower. Leaf freezing occurred even when the air temperature was above 0 °C. Ice nucleation at on average −2.6 °C started usually independently in each leaf, as the shoot is deep-seated in unfrozen soil. All the mesophyll cells were subjected to freezing cytorrhysis. Huge ice masses formed in the intercellular spaces of the spongy parenchyma. After thawing, photosynthesis was unaffected regardless of whether ice had formed. The cell walls were pectin-rich and triglycerides occurred, particularly in the spongy parenchyma. At high elevations, atmospheric temperatures fail to predict plant freezing. Shoot burial prevents ice spreading, specific tissue architecture enables ice management, and the flexibility of cell walls allows recurrent freezing cytorrhysis. The peculiar patterning of triglycerides close to ice rewards further investigation.
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Corey, Kenneth A., and Zhi-Yi Tan. "Induction of Changes in Internal Gas Pressure of Bulky Plant Organs by Temperature Gradients." Journal of the American Society for Horticultural Science 115, no. 2 (March 1990): 308–12. http://dx.doi.org/10.21273/jashs.115.2.308.
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Water manometers were connected to fruits of tomato (Lycopersicon esculentum Mill.) and pepper (Capsicum annuum L.), and then fruits were submerged in water baths providing initial temperature gradients between fruit and water of 0 to 19C. Apple (Malus domestics Borkh.) fruits, carrot (Daucus carota L.) roots, witloof chicory (Cichorium intybus L.) roots, rhubarb Rheum rhabarbarum L.) petioles, and pokeweed (Phytolacca americana L.) stems were subjected to water bath temperature gradients of 5C. Internal partial vacuums developed in all organs within minutes of imposing the gradients. The maximum partial vacuums in tomato and pepper fruits increased with increasing temperature gradients. Uptake of water accompanied changes in internal pressure reaching maxima of 17% (w/w) and 2% (w/w) of pepper and tomato fruits, respectively, after 22 hours. Maximum pressure changes achieved in bulky organs deviated from those predicted by the ideal gas law, possibly due to concomitant changes in gas pressure upon replacement of intercellular spaces with water and dissolution of CO2. Partial vacuums also developed in pepper fruits, rhubarb petioles, and pokeweed stems following exposure to air 15C cooler than initial organ temperatures. Results point to the role of temperature gradients in the transport of liquids and gases in plant organs.
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Kalachanis, D., and G. K. Psaras. "Structural Changes in Primary Lenticels of olea Europaea and Cercis Siliquastrum During The Year." IAWA Journal 28, no. 4 (2007): 445–56. http://dx.doi.org/10.1163/22941932-90001654.
Full textAbstract:
The structure of primary lenticels of the Mediterranean evergreen Olea europaea and the winter deciduous species Cercis siliquastrum was investigated during the year using scanning electron, conventional brightfield and epi-fluorescence microscopy. It was revealed that lenticels of O. europaea do not undergo significant structural changes over this time period. The filling tissue of O. europaea lenticels consists of fully-suberized cells that form small intercellular spaces. The air-exposed filling cells are replaced during spring and early summer by new early-suberized cells. Further notable structural modifications during the year were not observed. By contrast, lentice1s of C. siliquastrum possess a closing layer of suberized cells delimiting an underlying mass of non-suberized filling cells. During the period of high metabolie activity of the plant, i.e. during spring and early summer, the suberized closing layer is ruptured from the pressure exerted by the newly formed underlying cells. During late summer a new closing layer is formed, delimiting again the non-suberized underlying filling cells during winter. The possible role of lenticels in the gas exchange process is discussed. In both species the shade-adapted parenchyma cells of the cortex beneath lenticels shows bright red auto-fluorescence of chlorophyll, a phenomenon that is not yet fully understood.
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Han, Rong, Jialing He, Yixuan Chen, Feng Li, Hu Shi, and Yang Jiao. "Effects of Radio Frequency Tempering on the Temperature Distribution and Physiochemical Properties of Salmon (Salmo salar)." Foods 11, no. 6 (March 21, 2022): 893. http://dx.doi.org/10.3390/foods11060893.
Full textAbstract:
Salmon (Salmo salar) is a precious fish with high nutritional value, which is perishable when subjected to improper tempering processes before consumption. In traditional air and water tempering, the medium temperature of 10 °C is commonly used to guarantee a reasonable tempering time and product quality. Radio frequency tempering (RT) is a dielectric heating method, which has the advantage of uniform heating to ensure meat quality. The effects of radio frequency tempering (RT, 40.68 MHz, 400 W), water tempering (WT + 10 °C, 10 ± 0.5 °C), and air tempering (AT + 10 °C, 10 ± 1 °C) on the physiochemical properties of salmon fillets were investigated in this study. The quality of salmon fillets was evaluated in terms of drip loss, cooking loss, color, water migration and texture properties. Results showed that all tempering methods affected salmon fillet quality. The tempering times of WT + 10 °C and AT + 10 °C were 3.0 and 12.8 times longer than that of RT, respectively. AT + 10 °C produced the most uniform temperature distribution, followed by WT + 10 °C and RT. The amount of immobile water shifting to free water after WT + 10 °C was higher than that of RT and AT + 10 °C, which was in consistent with the drip and cooking loss. The spaces between the intercellular fibers increased significantly after WT + 10 °C compared to those of RT and AT + 10 °C. The results demonstrated that RT was an alternative novel salmon tempering method, which was fast and relatively uniform with a high quality retention rate. It could be applied to frozen salmon fillets after receiving from overseas catches, which need temperature elevation for further cutting or consumption.
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Schmidt, Flávio Luis, Hulda Noemi Mamani Chambi, and Julia Delgado Arid. "Dehydrated melon containing antioxidants and calcium from grape juice." Functional Foods in Health and Disease 6, no. 11 (November 30, 2016): 718. http://dx.doi.org/10.31989/ffhd.v6i11.281.
Full textAbstract:
Background: Grape juice has a high antioxidant potential, capable of fighting oxidative processes in the body. The juice is mainly marketed in its concentrated form, which has a high content of glucose and fructose. The juice concentrate may then be used as an osmotic agent to dehydrated fruit with a relatively short shelf-life at room temperature, such as melon. The osmotic dehydration process can also be combined with conventional drying in order to further reduce the water activity (aw) of the product. Finally, the antioxidant-rich melon meets the consumers’ demand for foods which contain ingredients that may impart health benefits. Results: Melon dehydrated by osmotic process at 200, 400 and 600 mbar, using grape juice concentrate (GJC), showed no significant differences in physical characteristics (aw, °Brix, and moisture content). Higher efficiency was observed when dehydration was performed at 200 mbar. After osmotic dehydration with GJC, both plasmolysis of the melon cells and an increase in intercellular spaces were observed by optical microscopy, with no negative impact on the mechanical properties (True stress, Hencky’s strain and deformability modulus). Calcium present in GJC was impregnated into the melon matrix, thus contributing with the mineral composition and mechanical properties of the final product. No significant differences were observed for the antioxidant capacity of melon dehydrated both with GJC and GJC followed by air-drying at 50 and 70°C. This demonstrates that it is possible to combine the two processes to obtain a product with intermediate moisture without decreasing its antioxidant capacity. The samples scored above the acceptable limit (>5) varying between like slightly to like moderately, resulting in a purchase intent with average scores between 3 (maybe/maybe not buy) and 4 (probably would buy).Conclusions: A product with intermediate water activity, acidic, firm, high antioxidant capacity, rich in calcium and in naturally occurring sugars, and potential sensory acceptance can be obtained using grape juice concentrate in the osmotic dehydration process, followed by air-drying process.Keywords: osmotic dehydration, air-drying, fruit juice, optical microscopy, antioxidants, calcium.