scholarly journals Are thick leaves, large mesophyll cells and small intercellular air spaces requisites for CAM?

2020 ◽  
Vol 125 (6) ◽  
pp. 859-868 ◽  
Author(s):  
Ana Herrera
Keyword(s):  
Cell Density ◽  
Leaf Anatomy ◽  
Isotopic Ratio ◽  
Leaf Thickness ◽  
Cell Area ◽  
Mesophyll Cells ◽  
Carbon Isotopic ◽  
Δ 13C ◽  
Cam Species ◽  
Nocturnal Acid Accumulation

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.

Detection of Adulterated Natural Sweeteners by Carbon Isotopic Ratio Analysis

2021 ◽  
Vol 36 (2) ◽  
pp. 148-153
Author(s):  
Hee-jin Choi ◽  
Jae-kyoo Lee ◽  
Ae-kyung Kim ◽  
Bo-kyeng Jung ◽  
Yun-jeong Yi ◽  
...  
Keyword(s):  
Isotopic Ratio ◽  
Ratio Analysis ◽  
Carbon Isotopic Ratio ◽  
Carbon Isotopic

scholarly journals STUDI ANATOMI DAUN CANTIGI (Vaccinium korinchense Ridl.) PADA ALTITUD BERBEDA DI GUNUNG TALANG

2017 ◽  
Vol 4 (1) ◽  
pp. 114
Author(s):  
. Alponsin ◽  
Tesri Maideliza ◽  
Zozy Aneloi Noli
Keyword(s):  
Data Analysis ◽  
Sea Level ◽  
Leaf Anatomy ◽  
Natural Sciences ◽  
Leaf Thickness ◽  
Survey Method ◽  
Leaf Section ◽  
Altitude Gradient ◽  
Cuticle Thickness

The study about leaf anatomy of Bilberry (Vaccinium korinchense RILD.)  at  altitude gradient on the Talang Mountain has been carried out in October to December 2015. The goal research is to compared that leaf thick tissues Bilbellry at altitude gradient. The sample were collected at Talang Mountain. The research used survey method and purpossive sampling with five altitude gradient (2200-2529 meter above sea level). Leaf section was maked  at the Plant  Structures developments Laboratory, Department Biology, Faculty of Mathematics and Natural Sciences, Andalas University. Data analysis used Kruskal-Wallis test. The results showed that leaf thickness, palisade and spongy thickness various between altitudes is sequentially 434-685 ?m, 183-322 ?m and 175-283 ?m . While epidermis thickness and cuticle thickness did not differ significantly between altitudes.

Leaf Ultrastructure and δ13C Values of Three Seagrasses from the Great Barrier Reef

1976 ◽  
Vol 3 (1) ◽  
pp. 9 ◽  
Author(s):  
ME Doohan ◽  
EH Newcomb
Keyword(s):  
Great Barrier Reef ◽  
Leaf Anatomy ◽  
Co2 Assimilation ◽  
Land Plants ◽  
Vascular Bundles ◽  
Barrier Reef ◽  
Thalassia Hemprichii ◽  
Mesophyll Cells ◽  
Δ13c Values ◽  
Abundant Cytoplasm

Leaf anatomy, ultrastructure and 13C/12C ratios were studied in three species of seagrasses collected on the Great Barrier Reef: Cymodocea rotundata Ehrenb. & Hempr., C. serrulata (R. Br.) Aschers. & Magnus, and Thalassia hemprichii (Ehrenb.) Aschers. Although they belong to two different mono- cotyledonous families, the three species are quite similar in the characteristics studied. Cells of the epidermal layer of the leaves are extremely thick-walled and have abundant cytoplasm with large chloroplasts and numerous mitochondria. The chloroplast-microbody profile ratio is c. 4-5 : 1 and the mitochondrion-microbody ratio 10-15 : 1. The epidermal cells resemble transfer cells in having a pronounced development of ingrowths on the radial walls. The mesophyll cells have thin walls, a large central vacuole and a thin layer of cytoplasm with relatively few organelles. There is no specialization of mesophyll cells around the vascular bundles. The δ13C values for the three sea- grasses range from -6.90, to - 12.40, and thus are characteristic of C4 land plants, although the seagrasses do not conform to the C4 syndrome in leaf anatomy or ultrastructure. It is not possible to place the seagrasses in either the C3, C4 or crassulacean acid metabolism category of land plants, but whether they constitute yet a fourth group with respect to characteristics related to CO2 assimilation is not clear.

scholarly journals Isotopic Ratios in Comets

1991 ◽  
Vol 116 (2) ◽  
pp. 879-895 ◽  
Author(s):  
V. Vanysek
Keyword(s):  
Isotopic Ratio ◽  
Chemical Fractionation ◽  
Interstellar Clouds ◽  
Outer Planets ◽  
Carbon Isotopic Ratio ◽  
Carbon Isotopic ◽  
Nuclear Species ◽  
Carbon Reservoir ◽  
Protosolar Nebula ◽  
The Individual

Abstract.The isotopic abundances depend on the universal evolution of elements and on the individual history of particular objects. Since it is believed that unprocessed material of the solar nebula is preserved in comets, the data concerning the abundance of stable isotopes in these primitive bodies are of some importance in the cosmological context. The present status of this problem is reviewed. The reliability of results for nuclear species with cosmological and cosmogonical implications, such as D/H, C 12/13, N 14/15, O 16/18, and Mg 24/25/26, is discussed. Significant variation is found for the isotopic abundance of carbon, depending upon which carbon reservoir is sampled. Deuterium is probably enhanced relative to the interstellar ratio. For other isotopes, the ratios are close to those of the terrestrial data. The tendency of the D/H ratio to be at higher values indicates a low temperature in the environment of the comet’s formation, and, together with similar effects in the outer planets, suggests that there were two different primordial reservoirs of deuterium in the solar system. The 12C/13C ratio inferred from in situ mass spectrometry of the dust, as well as from the ground-based optical spectra of the Swan band, tends to be approximately equal to the average terrestrial ratio (89) or larger. Recent results obtained from the CN band provide a significantly lower value (about 65), which corresponds to the carbon isotopic ratio in the diffuse interstellar clouds. The enhancement of deuterium and the possible differences of the carbon isotopic ratio in different species and refractory material are indicative of chemical fractionation processes in the protosolar nebula.

Leaf anatomy of tropical fern rheophytes, with its evolutionary and ecological implications

1992 ◽  
Vol 70 (1) ◽  
pp. 165-174 ◽  
Author(s):  
Masahiro Kato ◽  
Ryoko Imaichi
Keyword(s):  
Leaf Anatomy ◽  
Cell Expansion ◽  
Mesophyll Cells ◽  
Running Water ◽  
Unit Leaf ◽  
Flood Resistance ◽  
Stream Beds ◽  
Ecological Specificity ◽  
Wax Deposits ◽  
Cuticular Layer

Rheophytes are restricted to stream beds that are regularly flooded by swift-running water after rains and are morphologically characterized by having narrow, (ob)lanceolate leaves – leaflets (stenophylls) and other features that are adapted to the unique habitat, decreasing resistance to the swift-running water. The present study characterized anatomically the leaves of fern rheophytes. Generally, the mesophyll cells of rheophytes are less expanded, and therefore their intercellular spaces are smaller than those of related dryland species. Furthermore, frequency of occurrence of stomata per unit leaf area is greater, the cuticular layer is thicker, and the epicuticular wax deposits on the leaf epidermis are denser in at least some rheophytes than in related dryland species. It can be assumed that the stenophylls of the rheophytes are produced by developmental events, including weaker cell expansion than in dryland species, and that a phylogenetic decrease in cell expansion in leaves was involved in the origin of stenophylls from broader leaves of ancestral dryland species. The leaf anatomical features are discussed in relation to the ecological specificity of the rheophytes. Key words: evolution, flood resistance, intercellular space, leaf anatomy, rheophytic ferns, stenophyll.

Determination of Fatty Acids and Stable Carbon Isotopic Ratio in Subcutaneous Fat to Identify the Feeding Regime of Iberian Pigs

2015 ◽  
Vol 63 (2) ◽  
pp. 692-699 ◽  
Author(s):  
María Asunción López-Bascón ◽  
Feliciano Priego-Capote ◽  
Mónica Calderón-Santiago ◽  
Verónica Sánchez de Medina ◽  
José Manuel Moreno-Rojas ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Isotopic Ratio ◽  
Subcutaneous Fat ◽  
Stable Carbon ◽  
Feeding Regime ◽  
Carbon Isotopic Ratio ◽  
Carbon Isotopic

scholarly journals Super lithium-rich K giant with low 12C to 13C ratio

2018 ◽  
Vol 615 ◽  
pp. A74 ◽  
Author(s):  
Y. T. Zhou ◽  
J. R. Shi ◽  
H. L. Yan ◽  
Q. Gao ◽  
J. B. Zhang ◽  
...  
Keyword(s):  
Luminosity Function ◽  
Isotopic Ratio ◽  
Rotational Velocity ◽  
Equilibrium Analysis ◽  
Evolutionary Status ◽  
Evolutionary Stage ◽  
Low Carbon ◽  
Great Opportunity ◽  
Carbon Isotopic Ratio ◽  
Carbon Isotopic

Context. The lithium abundances in a few percent of giants exceed the value predicted by the standard stellar evolution models, and the mechanisms of Li enhancement are still under debate. The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) survey has obtained over six million spectra in the past five years, and thus provides a great opportunity to search these rare objects and to more clearly understand the mechanisms of Li enhancement. Aims. The aim of this work is to accurately measure the Li abundance and investigate the possible mechanisms of Li enrichment for a newly found super Li-rich giant, TYC 3251-581-1, located near the luminosity function bump with a low carbon isotopic ratio. Methods. Based on the high-resolution spectrum we obtained the stellar parameters (Teff, logg, [Fe/H]), and determined the elemental abundances of Li, C, N, α, Fe-peak, r-process, s-process elements, and the projected rotational velocity. For a better understanding of the effect of mixing processes, we also derived the 12C to 13C ratio, and constrained the evolutionary status of TYC 3251-581-1 based on the BaSTI stellar isochrones. Results. The super Li-rich giant TYC 3251-581-1 has A(Li) = 3.51, the average abundance of two lithium lines at λ = 6708 Å and 6104 Å based on the non-local thermodynamic equilibrium analysis. The atmospheric parameters show that our target locates on the luminosity function bump. The low carbon isotopic ratio (12C∕13C = 9.0), a slow rotational velocity vsini = 2.2 km s−1, and no sign of IR excess suggest that additional mixing after first dredge up (FDU) should occur to bring internal synthesized Li to the surface. The low carbon ([C∕Fe] ~−0.34) and enhanced nitrogen ([N∕Fe] ~ 0.33) are also consistent with the sign of mixing. Conclusions. Given the evolutionary stage of TYC 3251-581-1 with the relatively low 12C∕13C, the internal production which replenishes Li in the outer layer is the most likely origin of Li enhancement for this star.

Distribution of crassulacean acid metabolism in orchids of Panama: evidence of selection for weak and strong modes

2005 ◽  
Vol 32 (5) ◽  
pp. 397 ◽  
Author(s):  
Katia Silvera ◽  
Louis S. Santiago ◽  
Klaus Winter
Keyword(s):  
Crassulacean Acid Metabolism ◽  
Native Species ◽  
Acid Metabolism ◽  
Carbon Isotopic Composition ◽  
Bimodal Distribution ◽  
Carbon Isotopic ◽  
Acid Accumulation ◽  
Selection For ◽  
Cam Photosynthesis ◽  
Nocturnal Acid Accumulation

Crassulacean acid metabolism (CAM) is one of three metabolic pathways found in vascular plants for the assimilation of carbon dioxide. In this study, we investigate the occurrence of CAM photosynthesis in 200 native orchid species from Panama and 14 non-native species by carbon isotopic composition (δ13C) and compare these values with nocturnal acid accumulation measured by titration in 173 species. Foliar δ13C showed a bimodal distribution with the majority of species exhibiting values of approximately –28‰ (typically associated with the C3 pathway), or –15‰ (strong CAM). Although thick leaves were related to δ13C values in the CAM range, some thin-leaved orchids were capable of CAM photosynthesis, as demonstrated by acid titration. We also found species with C3 isotopic values and significant acid accumulation at night. Of 128 species with δ13C more negative than –22‰, 42 species showed nocturnal acid accumulation per unit fresh mass characteristic of weakly expressed CAM. These data suggest that among CAM orchids, there may be preferential selection for species to exhibit strong CAM or weak CAM, rather than intermediate metabolism.

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