The translocation of photosynthetically assimilated 14C in corn

1969 ◽  
Vol 47 (9) ◽  
pp. 1435-1442 ◽  
Author(s):  
G. Hofstra ◽  
C. D. Nelson
Keyword(s):  
Vascular Bundle ◽  
Leaf Blade ◽  
Vascular Bundles ◽  
Lateral Movement ◽  
Cutting Out ◽  
Corn Plants

A detailed study was made of translocation of photosynthetically assimilated 14C in 3- to 6-week-old corn plants. Corn assimilated 14C via malate and aspartate, and incorporated most of the 14C into sucrose, the only translocation compound. Lowering the temperature from 26° to 8 °C delayed the incorporation of 14C into sucrose, but had no effect on the distribution of 14C among the intermediates. Recent 14C assimilate was translocated very rapidly from the fed area, the amount remaining in the fed area decreasing logarithmically with time. The translocate moved down the vascular bundle it entered in the fed area, with no detectable lateral movement. The logarithmic profile in the leaf blade appeared to be the result of a temporary accumulation of the labelled pulse in the separate vascular bundles. This accumulation of sucrose in the veins could be eliminated by cutting out the fed area. Between 80 and 90% of the assimilated 14C was translocated from the fed area of the leaf in 24 hours with 50% moved out in the first 30 minutes. Both the rate of translocation and the total amount moved out of the fed area increased as the temperature was changed over the range 7 to 26 °C. Each leaf of young corn plants both imported assimilates from and exported assimilates to all other parts of the plant.

scholarly journals The utility of Bambusoideae (Poaceae, Poales) leaf blade anatomy for identification and systematics

2016 ◽  
Vol 76 (3) ◽  
pp. 708-717 ◽  
Author(s):  
T. D. Leandro ◽  
R. T. Shirasuna ◽  
T. S. Filgueiras ◽  
V. L. Scatena
Keyword(s):  
Vascular Bundle ◽  
Leaf Blade ◽  
Sympatric Species ◽  
Subsidiary Cell ◽  
Vascular Bundles ◽  
Diagnostic Features ◽  
Bulliform Cells ◽  
Herbaceous Bamboos ◽  
Stomatal Apparatus ◽  
Woody Bamboos

Abstract Bambusoideae is a diverse subfamily that includes herbaceous (Olyreae) and woody (Arundinarieae and Bambuseae) bamboos. Species within Bambusae are particularly difficult to identify due to their monocarpic lifecycle and the often long durations between mass flowering events; whereas the herbaceous bamboos are pluricarpic, but often are found with no reproductive structures. The leaf blade anatomy of 16 sympatric species of native Brazilian bamboos (Olyreae and Bambuseae) from the Atlantic Rainforest was studied in order to detect useful features for their identification. All the studied species share the following features: epidermis with a single stratum of cells; adaxial bulliform cells; mesophyll with arm cells, rosette cells, and fusoid cells; and collateral vascular bundles. Herbaceous bamboos share two features: papillae scattered on the abaxial surface and parallel-sided arrays of bulliform cells; whereas woody bamboos share: centrally organized papillae and fan-shaped arrays of bulliform cells. Also within the woody bamboos, intercostal fibers and a midrib with only one vascular bundle (simple midrib) characterize the subtribe Arthrostylidiinae; whereas a midrib with more than one vascular bundle (complex midrib) and a stomatal apparatus with two pappilae per subsidiary cell characterize the subtribe Chusqueinae. There are also diagnostic features for the sampled species, such as: papillae shape, and the outline and structure of the midrib. An identification key for all the studied species is provided based on the anatomical features.

scholarly journals Cross-sectional anatomy of leaf blade and leaf sheath of cogon grass (Imperata cylindrica L.)

2018 ◽  
Vol 25 ◽  
pp. 17-26
Author(s):  
SN Sima ◽  
AK Roy ◽  
MT Akther ◽  
N Joarder
Keyword(s):  
Vascular Bundle ◽  
Leaf Blade ◽  
Leaf Sheath ◽  
Bundle Sheath ◽  
Imperata Cylindrica ◽  
Saline Stress ◽  
Vascular Bundles ◽  
Bulliform Cells ◽  
Kranz Anatomy ◽  
Adaxial Epidermis

Histology of leaf blade and sheath of cogon grass (Imperata cylindrica L.) Beauv., indicated typical C4 Kranz anatomy. Cells of adaxial epidermis were smaller and bulliform cells were present on the adaxial epidermis. The shape of bulliform cells was bulbous; 3-7 cells were present in a group and 3-5 folds larger than epidermal cells. Three types of vascular bundles in respect of size and structure were extra large, large and small and they were part of leaf blade histology. These three sizes of vascular bundles were arranged in successive manner from midrib to leaf margin. Leaf sheath bundles were of two types: large and small. Extra large bundles were flanked by five small and four large bundles but small bundles were alternate found to be with large typed bundles. Extra large bundles were of typical monocotyledonous type but the large type had reduced xylem elements and the small typed was found to be transformed into treachery elements. Small be bundles occupied half the thickness of the flat portion of leaf blade topped by large bulliform cells of the adaxial epidermis. Extra large and large bundle had been extended to upper and lower epidermis. Kranz mesophyll completely encircled the bundle sheath and radiated out into ground tissue. Midrib was projected in abaxial direction and had a central vascular bundle with large and small bundles on either side of it along the abaxial regions. The midrib vascular bundle was devoid of chlorenchymatous bundle sheath and was of non-Kranz type. Continuous sub-epidermal sclerenchyma girders were noted as adaxial hypodermis. Anatomical traits exhibited an important adaptive defense against draught and saline stress of the plant. Quantitative measurement of various anatomical traits indicated strong variations among them.J. bio-sci. 25: 17-26, 2017

Leaf anatomy of the South African Danthonieae (Poaceae). V. Merxmuellera macowanii, M. davyi and M. aureocephala

Bothalia ◽  
1981 ◽  
Vol 13 (3/4) ◽  
pp. 493-500
Author(s):  
R. P. Ellis
Keyword(s):  
Light Microscopy ◽  
South African ◽  
Vascular Bundle ◽  
Leaf Anatomy ◽  
Related Species ◽  
Leaf Blade ◽  
Vascular Bundles ◽  
The South ◽  
Species Groups

Transverse sections and abaxial epidermal scrapes, of herbarium and freshly fixed leaf blade material, of Merxmuellera macowanii (Stapf) Conert, M. davyi (C. E. Hubb.) Conert and M. aureocephala (J. G. Anders.) Conert, were examined using light microscopy. The leaf anatomy o f these three species is very similar in all respects with the exception o f certain  M. aureocephala specimens. In addition, the anatomy indicates a relationship between these three species and M. disticha (Nees) Conert. This group of species differs anatomically from M. stricta (Schrad.) Nees, and related species such as  M. drakensbergensis (Schweick.) Conert and  M. stereophylla (J. G. Anders.) Conert, in the sequence of vascular bundles along the width of the leaf blade and associated characters. However, the M. aureocephala specimens, not having the  M. disticha type of vascular bundle arrangement, anatomically resemble the M. stricta group of species, and M. aureocephala appears to be intermediate between these two species groups.resemble the M. stricta group of species, and M. aureocephala appears to be intermediate between these two species groups.

Functional leaf anatomy and ultrastructure in a marine angiosperm, Syringodium isoetifolium (Aschers.) Dandy (Cymodoceaceae)

1993 ◽  
Vol 44 (1) ◽  
pp. 59 ◽  
Author(s):  
J Kuo
Keyword(s):  
Vascular Bundle ◽  
Leaf Blade ◽  
Small Region ◽  
Total Surface Area ◽  
Epidermal Cells ◽  
Secretory Cells ◽  
Vascular Bundles ◽  
Mesophyll Cells ◽  
Vascular Tissues ◽  
Syringodium Isoetifolium

The terete leaf blade of Syringodium isoetifolium (Aschers.) Dandy from south-western Australia has uniformly small epidermal cells and a few large secretory cells. Mesophyll tissues contain several air lacunae, a central longitudinal vascular bundle, and eight to twelve peripheral longitudinal vascular bundles, but no fibre bundles. The total volume of air lacunae is about 10% that of the leaf blades, but the total surface area of air lacunae is similar to that of leaf blades. The leaf cuticle appears as a thin, electron-transparent layer. Leaf-blade epidermal cells have a large central vacuole and peripheral cytoplasm containing many chloroplasts that lack starch grains. Wall ingrowths are absent. However, the small region between the walls and the plasmalemma could play an important role in nutrient absorption. Plasmodesmata appear to be absent between adjacent epidermal cells, and also between epidermal and mesophyll cells, suggesting that there is only an apoplastic pathway for the transport of photosynthate to the vascular tissues. Each vascular bundle is surrounded by a layer of sheath cells, which are characterized by the presence of suberized lamellae in their walls. These may act to reduce the apoplastic exchange of solutes and water between the mesophyll and vascular tissues. Xylem elements, represented by large lumens and intensely hydrolysed walls, may not be present in all peripheral vascular bundles. Two types of sieve elements occur in S. isoetifolium leaf blades: normal thin-walled ones with large lumens, and thick-walled ones with reduced lumens, representing the photophloem and the metaphloem, respectively.

scholarly journals Knockout of Auxin Response Factor SlARF4 Improves Tomato Resistance to Water Deficit

2021 ◽  
Vol 22 (7) ◽  
pp. 3347
Author(s):  
Mengyi Chen ◽  
Xiaoyang Zhu ◽  
Xiaojuan Liu ◽  
Caiyu Wu ◽  
Canye Yu ◽  
...  
Keyword(s):  
Water Stress ◽  
Water Deficit ◽  
Vascular Bundle ◽  
Plant Resistance ◽  
Quantitative Polymerase Chain Reaction ◽  
Photochemical Efficiency ◽  
Differentially Expressed ◽  
Vascular Bundles ◽  
Aba Signaling ◽  
Auxin Response

Auxin response factors (ARFs) play important roles in various plant physiological processes; however, knowledge of the exact role of ARFs in plant responses to water deficit is limited. In this study, SlARF4, a member of the ARF family, was functionally characterized under water deficit. Real-time fluorescence quantitative polymerase chain reaction (PCR) and β-glucuronidase (GUS) staining showed that water deficit and abscisic acid (ABA) treatment reduced the expression of SlARF4. SlARF4 was expressed in the vascular bundles and guard cells of tomato stomata. Loss of function of SlARF4 (arf4) by using Clustered Regularly Interspaced Short Palindromic Repeats/Cas 9 (CRISPR/Cas 9) technology enhanced plant resistance to water stress and rehydration ability. The arf4 mutant plants exhibited curly leaves and a thick stem. Malondialdehyde content was significantly lower in arf4 mutants than in wildtype plants under water stress; furthermore, arf4 mutants showed higher content of antioxidant substances, superoxide dismutase, actual photochemical efficiency of photosystem II (PSII), and catalase activities. Stomatal and vascular bundle morphology was changed in arf4 mutants. We identified 628 differentially expressed genes specifically expressed under water deficit in arf4 mutants; six of these genes, including ABA signaling pathway-related genes, were differentially expressed between the wildtype and arf4 mutants under water deficit and unlimited water supply. Auxin responsive element (AuxRE) elements were found in these genes’ promoters indicating that SlARF4 participates in ABA signaling pathways by regulating the expression of SlABI5/ABF and SCL3, thereby influencing stomatal morphology and vascular bundle development and ultimately improving plant resistance to water deficit.

scholarly journals Mechanical behavior of 'Niagara Rosada' grape berry detachment

2011 ◽  
Vol 31 (6) ◽  
pp. 1115-1122 ◽  
Author(s):  
Daniel Gomes ◽  
Antonio C. de O Ferraz
Keyword(s):  
Mechanical Behavior ◽  
Vascular Bundle ◽  
Traction Force ◽  
Grape Berry ◽  
Vascular Bundles ◽  
Test Results ◽  
Deformation Curves ◽  
Considerable Portion ◽  
Surrounding Skin ◽  
Niagara Rosada

The 'Niagara Rosada' grape is the main Brazilian table grape belonging to the Labrusca family. It develops medium, cylindrical and compact bunches with berries presenting a pinkish skin and a foxy flavor that is valued in the Brazilian market. These berries are tender and have a pedicel-berry connection provided by the vascular bundles and surrounding skin. This cultivar is very susceptible to berry drop mainly caused by vibration and senescence. The objective of this study was to evaluate the temporal mechanical behavior of the pedicel-berry detachment, using resistance indexes extracted from traction force-deformation curves. Test results showed two different detachment types. In the first one, which exhibited higher average resistance, a considerable portion of the vascular bundle came out attached to the pedicel and in the second type; the vascular bundle was retained inside the berry. The proposed indexes based on maximum detachment force, force at 0.2; 0.5; 1.0 and 1.2 mm, and maximum force to corresponding deformation ratio did not discriminate the senescence of the berry.

Early ontogeny defines the diversification of primary vascular bundle systems in angiosperms

2020 ◽  
Author(s):  
Regine Claßen-Bockhoff ◽  
Doris Franke ◽  
Hansjörg Krähmer
Keyword(s):  
Vascular Bundle ◽  
Vascular Tissue ◽  
Three Dimensional ◽  
Early Ontogeny ◽  
Leaf Primordia ◽  
Dimensional System ◽  
Vascular Bundles ◽  
Histological Data ◽  
Molecular Aspects ◽  
The One

Abstract Understanding vascular bundle systems in angiosperms is a challenge. On the one hand, the vascular tissue is extremely important in reconstructing the evolution and survivability of plants, but on the other hand, it forms a complicated three-dimensional system of controversially discussed phylogenetic and ontogenetic origin. To increase clarity, in this paper we briefly summarize histological, phylogenetic and molecular aspects of primary vascular bundle formation in angiosperms, adding histological data on early stages of vascular bundle formation, proposing a concept combining the different views and providing simplified illustrations to improve the understanding of primary vascular systems in angiosperms. Based on the auxin hypothesis, vascular bundle formation is stimulated by the development of leaf primordia. Provascular domains appear at the base of the leaf primordia and develop into two directions (leaf, internode). The low vs. high number of internodal bundles, their circular vs. scattered arrangement and the open vs. closed bundle construction in eudicots vs. monocots can be deduced to be due to processes below the shoot apical meristem. The most important processes distinguishing monocots from eudicots are the isolated bundle initiation outside the primary meristem, the enormous expansion of the leaf bases associated with a high number of vascular bundles and the early onset of primary thickening passively dislocating vascular bundles.

Leaf structure in Amorimia and closely related Neotropical genera and implications for their systematics and leaf evolution in Malpighiaceae

2019 ◽  
Vol 191 (1) ◽  
pp. 102-127
Author(s):  
Ana Caroline Marques Pereira Mello ◽  
Rafael Felipe De Almeida ◽  
André Marcio Araújo Amorim ◽  
Denise Maria Trombert Oliveira
Keyword(s):  
Phylogenetic Tree ◽  
Vascular Bundle ◽  
Leaf Blade ◽  
Leaf Structure ◽  
Palisade Parenchyma ◽  
Generic Delimitation ◽  
Leaf Evolution ◽  
Comprehensive Study

AbstractAmorimia (Malpighiaceae) was recently segregated from the polyphyletic Mascagnia and placed in the malpighioid clade; identifying new characters based on leaf structure is among the first steps towards a proper generic delimitation of these segregates of Mascagnia. A comprehensive study describing and testing the relevance of leaf-structure characters in the evolution of Amorimia and related Neotropical genera is presented. We sampled all 15 Amorimia spp. and, as outgroups, eight species from the closely related Neotropical genera (Diplopterys, Ectopopterys, Mascagnia, Peixotoa and Stigmaphyllon). We scored 85 structural characters and mapped them on the most recent phylogenetic tree recovered for the genera. The presence of druses in the palisade parenchyma, the position of fibres alongside the vascular bundle and the occurrence of fibre blocks near the margin of the leaf blade were recovered as anatomical synapomorphies for Amorimia. Our results are a first step towards recovering anatomical and macromorphological synapomorphies for newly identified lineages of Malpighiaceae, such as Amorimia.

scholarly journals Anatomical Structure and Terpenoid Content of Zodia (Evodia suaveolens Scheff) Leaves

2020 ◽  
Vol 20 ◽  
pp. 03001
Author(s):  
Evi Mintowati Kuntorini ◽  
Dewi Nofaliana ◽  
Eny Dwi Pujawati
Keyword(s):  
Vascular Bundle ◽  
Anatomical Structure ◽  
Vascular Bundles ◽  
Oil Glands ◽  
Abaxial Epidermis ◽  
Embedding Method ◽  
Histochemical Assay ◽  
Paraffin Embedding ◽  
Histochemical Test ◽  
Leaf Anatomical Structure

Zodia (Evodia suaveolens Scheff) is a member of Rutaceae contain terpenoids, triterpenoids, alkaloids, flavonoids, and xanthones which have anti-mosquito activity. This research aimed to observe the anatomical structure, the location, and distribution of terpenoid based on the leaves' age. Anatomical slides preparation of leaves were made using the paraffin embedding method with safranin staining. The distribution of terpenoid was analyzed by the histochemical assay. Leaf anatomical structure shows that the 3rd and 6th leaf bifacial (dorsiventral) consisted of the upper epidermis, mesophyll (palisade and sponge), collateral vascular bundle, parenchyma midrib, abaxial epidermis and oil glands in mesophyll that is underneath both epidermises. The diameter of oil glands with larger sizes was on the 6th leaf, whereas the density is not different in the 3rd and 6th leaves. The histochemical test showed that terpenoid was observed in the leaf vascular bundles, oil glands, and epidermis.

Influence, chez le Manihot esculenta, du développement de la lame du limbe sur celui du pétiole et de l'entre-noeud sous-jacent

1992 ◽  
Vol 70 (10) ◽  
pp. 2053-2065 ◽  
Author(s):  
R. Médard ◽  
J. M. N. Walter ◽  
P. Barnola
Keyword(s):  
Key Words ◽  
Vascular Bundle ◽  
Manihot Esculenta ◽  
Vascular Development ◽  
Vascular Bundles ◽  
Mechanical Pressure ◽  
Vascular Tissues ◽  
Growth Area

Within each internode and about four plastochrons after its formation, an intercalary growth area appears, leading to a continued lengthening due essentially to anticline mitoses. It temporarily looks like a cambium. The blade of the leaf which is directly above the internode is absolutely necessary for the formation of this growth area. Xylem integrity of the cauline vascular bundle connected with this leaf is also required. Within each leaf, the presence of the blade and the integrity of vascular bundles are also indispensable for the lengthening of the petiole, whose mitotic system resembles the internode's. The hypothesis of a blade influence on the mitotic lengthening system through mechanical pressure due to the vascular development is discussed. Key words: internode, petiole, blade, vascular tissues, Manihot esculenta, intercalary growth.

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