Compartmentation in Vicia faba Leaves. III. Photosynthesis in the Spongy and Palisade Parenchyma

1975 ◽  
Vol 2 (3) ◽  
pp. 435 ◽  
Author(s):  
WH Outlaw ◽  
DB Fisher
Keyword(s):  
Water Soluble ◽  
Glyceric Acid ◽  
Spongy Parenchyma ◽  
Palisade Parenchyma ◽  
Palisade And Spongy Parenchyma ◽  
Phosphoglyceric Acid ◽  
Rate Of Photosynthesis ◽  
Photosynthetic Carbon Metabolism ◽  
Sugar Phosphates ◽  
Kinetics Of

Relative rates of photosynthesis in the palisade and spongy parenchyma were found to be dependent upon the intensity of incident photosynthetically active radiation. The rate of photosynthesis in the spongy parenchyma relative to the rate in the palisade parenchyma increased with increasing light intensity. We attribute this behaviour to shading of the spongy parenchyma by palisade parenchyma. The kinetics of photosynthetic carbon metabolism were qualitatively similar in the two tissues. Immediately after a 6-s 14CO2 pulse, phosphoglyceric acid plus sugar phosphates represented about 85 % of the 14C in the water-soluble compounds in both the palisade and spongy parenchyma, and were the only compounds in which radioactivity declined. Sucrose was the main end-product of photosynthesis and represented 30% of the water-soluble radioactivity after 104 s in both these tissues. Other compounds (phosphoglycollic acid plus phosphoenolpyruvic acid, malic acid plus glyceric acid, and alanine) represented smaller, similar amounts of radioactivity in each tissue. A higher proportion of activity due to 14C-labelled (glycine plus serine) in the water-soluble fraction of the spongy parenchyma may reflect a difference in the proportion of photosynthate being respired there.

CO2 and Temperature-dependent Induction in C4 Photosynthesis: an Approach to the Hierarchy of Rate-limiting Processes

1997 ◽  
Vol 24 (4) ◽  
pp. 505 ◽  
Author(s):  
Agu Laisk ◽  
Gerald E. Edwards
Keyword(s):  
C4 Photosynthesis ◽  
Co2 Concentration ◽  
Temperature Dependent ◽  
Co2 Response ◽  
Amaranthus Cruentus ◽  
Low Co2 ◽  
Phosphoglyceric Acid ◽  
Rate Of Photosynthesis ◽  
Rate Limiting ◽  
Kinetics Of

Rate-limiting processes for C4 photosynthesis were examined in Sorghum bicolor, an NADP-ME type species, and Amaranthus cruentus, an NAD-ME type C4 species, by studying the kinetics of transient changes in photosynthetic rates following rapid changes in CO2 or temperature. Primary responses (faster than 15 s) to increasing CO2 or temperature are considered direct effects on the turnover rate of the C4 cycle, whereas medium transient changes (2–3 min) are considered due to build-up of C4 cycle intermediates, and the slowest transient changes (20–30 min) are thought to be related to end product synthesis. Reciprocal plot of carboxylation rates versus cell wall (dissolved) CO2 concentration (Cw) gives an apparent Km (CO2) of 8 µM and a Vm of 200 µmol m-2 s-1 for PEP carboxylase, which is about 4 times higher than the maximum rate of photosynthesis. Under strictly limiting CO2, the rate of PEP carboxylation in C4 photosynthesis is independent of temperature (20–35°C), suggesting a physical rather than a biochemical limitation. It is suggested that the rates of C3 and C4 cycles are coordinated through the pool sizes of the C4 cycle, which are in equilibrium with the pool of 3-phosphoglyceric acid. At low CO2, the C4 pools decrease and are slowly regenerated at elevated CO2, restricting the CO2 response of C4 photosynthesis.

scholarly journals Leaf Morphoanatomy and Biochemical Variation on Coffee Cultivars Under Drift Simulation of Glyphosate

2018 ◽  
Vol 36 ◽  
Author(s):  
L.A.C. REIS ◽  
F.P. CARVALHO ◽  
A.C. FRANÇA ◽  
D.M.T. FRANCINO ◽  
N.A.V.D. PINTO ◽  
...  
Keyword(s):  
Total Phenols ◽  
Total Thickness ◽  
Spongy Parenchyma ◽  
Palisade Parenchyma ◽  
Abaxial Epidermis ◽  
Blade Thickness ◽  
Palisade And Spongy Parenchyma ◽  
Biochemical Variation ◽  
Glyphosate Drift ◽  
Higher Doses

ABSTRACT: The most widely used herbicide in coffee crop is glyphosate, it inhibits the biosynthesis of secondary metabolites, responsible for structures and substances of plant defense. This work aimed to evaluate the morphoanatomy, total phenols, flavonoids and caffeine in leaves of Arabica coffee submitted to different sub-doses of glyphosate. The treatments were combinations of three coffee cultivars (MGS Travessia, Oeiras MG 6851 and Catuaí IAC 144) and five sub-doses of glyphosate (0.0, 57.6, 115.2, 230.4 and 460.8 g a.e. ha-1). The total thickness of the leaf blade, thickness of adaxial and abaxial epidermis, palisade and spongy parenchyma, in addition to the total phenol, total flavonoids and caffeine were evaluated 30 days after spraying. Catuaí showed a reduction in the total leaf thickness, while the others cultivars had an increase. The thickness of adaxial and abaxial epidermis and palisade parenchyma was reduced, and the spongy parenchyma increased with increasing doses of glyphosate, regardless of the cultivars. There was an increase on the total phenols up to 115.2 g ha-1 glyphosate, and above this dose, the concentrations of phenols were reduced. The Travessia and Oeiras cultivars obtained a reduction of flavonoids up to 115.2 g ha-1; and above this dose, the concentration of flavonoids increased. The Catuaí cultivar showed an opposing behavior of the concentration of flavonoids. Oeiras and Catuaí showed a decrease of caffeine up to 115.2 g ha-1 and an increase at higher doses. Travessia showed an increase of caffeine in sub-doses above 115.2 g ha-1. The three cultivars showed a higher concentration of phenols in the palisade parenchyma after the application of glyphosate drift. Glyphosate reduces the thickness of the adaxial and abaxial epidermis and palisade parenchyma, and increases the thickness of spongy parenchyma. Doses of glyphosate above 230.4 g ha-1 result in the reduction of total phenols. The concentration of flavonoids and caffeine has varying effects with glyphosate application.

Fertilisation residues alter leaf scleromorphy in an evergreen savannah shrub (Maprounea brasiliensis, Euphorbiaceae)

2013 ◽  
Vol 61 (4) ◽  
pp. 266 ◽  
Author(s):  
Marina Neves Delgado ◽  
Misléia Rodrigues de Aguiar Gomes ◽  
Sônia Nair Báo ◽  
Davi Rodrigo Rossatto
Keyword(s):  
Agricultural Production ◽  
Leaf Traits ◽  
Residual Effects ◽  
Control Group ◽  
Leaf Mass Per Area ◽  
Spongy Parenchyma ◽  
Palisade Parenchyma ◽  
Qualitative And Quantitative ◽  
Brazilian Savannah ◽  
Palisade And Spongy Parenchyma

In the present study, we examined how residues of nitrogen (N), phosphorus (P) and calcium (Ca) fertilisers affect leaf anatomical traits in Maprounea brasiliensis (Euphorbiaceae), a typical and dominant cerrado (Brazilian savannah) species adapted to dystrophic soils. We predicted that fertiliser residues would alter qualitative and quantitative aspects of M. brasiliensis leaves and would decrease their scleromorphy. Leaves were sampled from plants that were growing in soils previously fertilised with N, P and Ca and in plants that were growing in soils without fertiliser residues. We measured the thickness of the cuticle, the epidermis of adaxial and abaxial surfaces, thickness of palisade parenchyma and spongy parenchyma, total thickness of the leaf, total area of the midrib and leaf mass per area (LMA). We found that plants under fertiliser residues produced fewer scleromorphic leaves with low LMA, thinner cuticle and epidermis and thicker palisade and spongy parenchyma. They also showed a decrease in the size and area occupied by the leaf midvein. However, plants under fertiliser residues produced similar leaf thickness as did the plants in the control group. Our results showed that residual effects of fertilisation changed structural patterns of a typical species of cerrado. Thus, further studies about fertilisation effects on leaf traits are needed because larger areas of the central cerrado are being occupied for agricultural production.

I. Intrazellulärer Transport von Zwischenprodukten der Photosynthese im Photosynthese-Gleichgewicht und im Dunkel-Licht-Dunkel-Wechsel

1967 ◽  
Vol 22 (11) ◽  
pp. 1189-1199 ◽  
Author(s):  
U. Heber ◽  
K. A. Santarius ◽  
M. A. Hudson ◽  
U. W. Hallier
Keyword(s):  
Steady State ◽  
Phosphate Esters ◽  
Dark Light ◽  
Regulation Of Metabolism ◽  
Large Fluctuations ◽  
Phosphoglyceric Acid ◽  
Intact Leaves ◽  
Sugar Phosphates ◽  
Kinetics Of

1. The distribution — before, during and after photosynthesis — of different phosphate esters in chloroplasts and cytoplasm of leaf cells of spinach and Elodea has been investigated. In steady state experiments intact leaves were fed, during illumination, with 14CO2. The kinetics of the distribution of labelled phosphate esters between chloroplasts and cytoplasm were determined. In further experiments with intact leaves fluctuations in the pool sizes of phosphate esters in chloroplasts and in the cytoplasm were recorded in the dark/light and the light/dark transient. Independent fluctuations served as an indication that little or no exchange between chloroplasts and cytoplasm takes place. Concomitant fluctuations suggest rapid exchange.2. Although labelling takes place in the chloroplasts, a number of labelled phosphorylated intermediates appear rapidly in the cytoplasm during steady state photosynthesis of intact leaves in the presence of 14CO2. This is particularly true for phosphoglyceric acid, glucose-6-phosphate, fructose-6-phosphate and fructose-1,6-diphosphate. On the other hand, labelled ribulosediphosphate, sedoheptulosediphosphate and sedoheptulosemonophosphate remain largely in the chloroplasts. This agrees with earlier work on the behaviour of phosphorylated intermediates during the induction period of photosynthesis.3. In the dark the level of the bulk of the sugar diphosphates is lower in the chloroplasts than in the cytoplasm of intact leaves. On illumination, a large accumulation occurs only in the chloroplasts. This behaviour suggests impermeability of the chloroplast membrane towards at least some of the sugar diphosphates. In contrast, concomitant large fluctuations in the levels of dihydroxyacetonephosphate and fructose-1,6-diphosphate have been observed during the transients from dark to light and vice versa in chloroplasts and cytoplasm alike indicating that at least one of these compounds functions as a transport metabolite. Changes in the concentrations of glucose-6-phosphate and fructose-6-phosphate were much smaller under the influence of light than those of other sugar phosphates.4. The results demonstrate the role of phosphorylated transport metabolites in carbon metabolism in chloroplasts and cytoplasm. Implications of these findings in relation to photosynthesis, respiration and the regulation of metabolism are discussed.

scholarly journals The Morphological and Anatomical Traits of the Leaf in Representative Vinca Species Observed on Indoor- and Outdoor-Grown Plants

Plants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 622
Author(s):  
Alexandra Ciorîță ◽  
Septimiu Cassian Tripon ◽  
Ioan Gabriel Mircea ◽  
Dorina Podar ◽  
Lucian Barbu-Tudoran ◽  
...  
Keyword(s):  
Spongy Parenchyma ◽  
Palisade And Spongy Parenchyma ◽  
Chemical Composition Of Plants ◽  
Ultrastructural Characteristics ◽  
Species Specific ◽  
Microscopy Techniques ◽  
First Time ◽  
Thick Layers ◽  
Space Ratio ◽  
Indoor And Outdoor

Morphological and anatomical traits of the Vinca leaf were examined using microscopy techniques. Outdoor Vinca minor and V. herbacea plants and greenhouse cultivated V. major and V. major var. variegata plants had interspecific variations. All Vinca species leaves are hypostomatic. However, except for V. minor leaf, few stomata were also present on the upper epidermis. V. minor leaf had the highest stomatal index and V. major had the lowest, while the distribution of trichomes on the upper epidermis was species-specific. Differentiated palisade and spongy parenchyma tissues were present in all Vinca species’ leaves. However, V. minor and V. herbacea leaves had a more organized anatomical aspect, compared to V. major and V. major var. variegata leaves. Additionally, as a novelty, the cellular to intercellular space ratio of the Vinca leaf’s mesophyll was revealed herein with the help of computational analysis. Lipid droplets of different sizes and aspects were localized in the spongy parenchyma cells. Ultrastructural characteristics of the cuticle and its epicuticular waxes were described for the first time. Moreover, thick layers of cutin seemed to be characteristic of the outdoor plants only. This could be an adaptation to the unpredictable environmental conditions, but nevertheless, it might influence the chemical composition of plants.

scholarly journals A new species of Anemopaegma (Bignonieae, Bignoniaceae) from the Atlantic Forest of Brazil

Phytotaxa ◽  
2015 ◽  
Vol 219 (2) ◽  
pp. 174
Author(s):  
Fabiana Firetti Leggieri ◽  
DIEGO DEMARCO ◽  
LÚCIA G. LOHMANN
Keyword(s):  
New Species ◽  
Species Diversity ◽  
Biodiversity Conservation ◽  
Atlantic Forest ◽  
Axillary Buds ◽  
Spongy Parenchyma ◽  
Palisade Parenchyma ◽  
Separate Species ◽  
Anatomical Studies ◽  
A New Species

The Atlantic Forest of Brazil includes one of the highest species diversity and endemism in the planet, representing a priority for biodiversity conservation. A new species of Anemopaegma from the Atlantic Forest of Brazil is here described, illustrated and compared to its closest relatives. Anemopaegma nebulosum Firetti-Leggieri & L.G. Lohmann has been traditionally treated as a morph of Anemopaegma prostratum; however, additional morphological and anatomical studies indicated that A. nebulosum differs significantly from A. prostratum and is best treated as a separate species. More specifically, A. nebulosum is characterized by elliptic and coriaceous leaflets (vs. ovate to orbicular and membranaceous in A. prostratum), smaller leaflet blades (3.6–5.5 x 2.0–3.0 cm vs. 6.7–13.0 x 4.2–8.4 cm in A. prostratum), orbicular prophylls of the axillary buds (vs. no prophylls in A. prostratum), solitary flowers (vs. multi-flowered axillary racemes in A. prostratum) and a gibbous corolla (vs. infundibuliform corollas in A. prostratum). In addition, A. nebulosum differs from A. prostratum anatomically in having thicker leaflet blades composed of two to four layers of palisade parenchyma (vs. one to three layers in A. prostratum), and seven to eight layers in the spongy parenchyma (vs. six to eight layers in A. prostratum). A key for the identification of all species of Anemopaegma from the Atlantic Forest of Brazil is presented.

scholarly journals Comparative Study on Gas Exchange, Water Relations and Leaf Anatomy of Two Olive Cultivars Grown under Well-Irrigated and Drought Conditions

1999 ◽  
Vol 54 (9-10) ◽  
pp. 688-692 ◽  
Author(s):  
Konstantinos Chartzoulakis ◽  
Angelos Patakas ◽  
Artemis Bosabalidis
Keyword(s):  
Gas Exchange ◽  
Water Relations ◽  
Volume Fraction ◽  
Spongy Parenchyma ◽  
Intercellular Spaces ◽  
Palisade Parenchyma ◽  
Mesophyll Cells ◽  
Olive Cultivars ◽  
Olea Europea ◽  
Leaf Anatomical Characteristics

The effect of water stress on gas exchange, water relations and leaf anatomical characteristics have been studied in two olive cultivars (Olea europea, L. cv. ‘Koroneiki’ and cv. ‚Mastoidis’). Photosynthetic rate as well as stomatal conductance were decreased in stressed plants. Osmotic potential (π) declined rapidly in stressed plants indicating their ability for osmoregulation. Bulk modulus of elasticity (ε) was significantly higher in stressed compared to well irrigated plants. The volume fraction of intercellular spaces of the upper palisade parenchyma, the spongy parenchyma as well as the lower palisade parenchyma were significantly lower in stressed compared to well irrigated plants. On the other hand, the density of mesophyll cells in the upper palisade parenchyma, spongy parenchyma and lower palisade parenchyma increased significantly in stressed plants

scholarly journals Mixing state and compositional effects on CCN activity and droplet growth kinetics of size-resolved CCN in an urban environment

2012 ◽  
Vol 12 (21) ◽  
pp. 10239-10255 ◽  
Author(s):  
L. T. Padró ◽  
R. H. Moore ◽  
X. Zhang ◽  
N. Rastogi ◽  
R. J. Weber ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Water Soluble ◽  
Anthropogenic Sources ◽  
Droplet Growth ◽  
Mixing State ◽  
Aerosol Composition ◽  
Activation Kinetics ◽  
Aerosol Mixing State ◽  
Kinetics Of ◽  
Ccn Activity

Abstract. Aerosol composition and mixing state near anthropogenic sources can be highly variable and can challenge predictions of cloud condensation nuclei (CCN). The impacts of chemical composition on CCN activation kinetics is also an important, but largely unknown, aspect of cloud droplet formation. Towards this, we present in-situ size-resolved CCN measurements carried out during the 2008 summertime August Mini Intensive Gas and Aerosol Study (AMIGAS) campaign in Atlanta, GA. Aerosol chemical composition was measured by two particle-into-liquid samplers measuring water-soluble inorganic ions and total water-soluble organic carbon. Size-resolved CCN data were collected using the Scanning Mobility CCN Analysis (SMCA) method and were used to obtain characteristic aerosol hygroscopicity distributions, whose breadth reflects the aerosol compositional variability and mixing state. Knowledge of aerosol mixing state is important for accurate predictions of CCN concentrations and that the influence of an externally-mixed, CCN-active aerosol fraction varies with size from 31% for particle diameters less than 40 nm to 93% for accumulation mode aerosol during the day. Assuming size-dependent aerosol mixing state and size-invariant chemical composition decreases the average CCN concentration overprediction (for all but one mixing state and chemical composition scenario considered) from over 190–240% to less than 20%. CCN activity is parameterized using a single hygroscopicity parameter, κ, which averages to 0.16 ± 0.07 for 80 nm particles and exhibits considerable variability (from 0.03 to 0.48) throughout the study period. Particles in the 60–100 nm range exhibited similar hygroscopicity, with a κ range for 60 nm between 0.06–0.076 (mean of 0.18 ± 0.09). Smaller particles (40 nm) had on average greater κ, with a range of 0.20–0.92 (mean of 0.3 ± 0.12). Analysis of the droplet activation kinetics of the aerosol sampled suggests that most of the CCN activate as rapidly as calibration aerosol, suggesting that aerosol composition exhibits a minor (if any) impact on CCN activation kinetics.

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