Effect of secondary growth on the conformation and permeability of the endodermis of broad bean (Vicia faba), sunflower (Helianthus annuus), and garden balsam (Impatiens balsamina)

1984 ◽  
Vol 62 (5) ◽  
pp. 907-910 ◽  
Author(s):  
Carol Ann Weerdenburg ◽  
Carol A. Peterson
Keyword(s):  
Cross Sections ◽  
Broad Bean ◽  
Uv Light ◽  
Secondary Growth ◽  
Root Extract ◽  
Chelidonium Majus ◽  
Calcofluor White ◽  
Casparian Band ◽  
Apoplastic Barrier ◽  
Endodermal Cells

A root undergoing secondary growth exhibits massive girth increases owing to the activity of the vascular cambium. To determine the effects of this growth on endodermal structure and function, cleared cross sections from areas of primary and secondary growth in broad bean, sunflower, and garden balsam roots were examined. Casparian bands were detected by staining the sections with Chelidonium majus root extract and viewing them with ultraviolet (uv) light using an epifluorescence microscope. Endodermal diameter and numbers of endodermal cells increased dramatically in the area of secondary growth. The distance spanned by the Casparian band (i.e., the tangential width of the endodermal cells) between radial walls also increased except in sunflower. The permeability of the endodermis to an apoplastic fluorescent dye in roots undergoing secondary growth was tested by treatment with Calcofluor white M2R. In all species examined, the Casparian band continued to function as an effective apoplastic barrier during early stages of secondary growth despite the increase in endodermal cell size and number. Eventual decortication with concurrent disruption of the endodermis resulted in massive penetration of Calcofluor white M2R into the xylem.

Structural changes in phi thickenings during primary and secondary growth in roots. 1. Apple (Pyrus malus) Rosaceae

1983 ◽  
Vol 61 (10) ◽  
pp. 2570-2576 ◽  
Author(s):  
Carol Ann Weerdenburg ◽  
Carol A. Peterson
Keyword(s):  
Cross Sections ◽  
Structural Changes ◽  
Lateral Roots ◽  
Secondary Growth ◽  
Root Tip ◽  
Root Extract ◽  
Chelidonium Majus ◽  
Cortical Cells ◽  
Lateral Root Primordia ◽  
Mature Root

Whole roots and freehand cross sections of apple roots, cleared and stained with a root extract of Chelidonium majus L., revealed the presence of a uniseriate layer of phi thickenings. The layer, externally adjacent to the endodermis, consisted of cells with a heavy deposition of lignin in the thickened midportions of their transverse and radial walls. The thickenings were completely developed within 3–5 mm from the root tip. Lateral root primordia emerged through the phi layer by means of openings in the layer resulting from the removal of entire phi thickenings from the cortical cells. The layer was not continuous from the main to the lateral roots unlike the Casparian band of the endodermis. During secondary growth, the middle lamellae of the cells of the phi layer split, disrupting the regular appearance of the layer. Ultimately, the epidermis and cortex were sloughed off as the periderm, arising in the pericycle, developed to form the most external tissue of the mature root. However, remnants of the phi thickenings were persistent in many areas of the mature root.

Development of Casparian bands and suberin lamellae in the endodermis of onion roots

1992 ◽  
Vol 70 (11) ◽  
pp. 2233-2237 ◽  
Author(s):  
Alban D. Barnabas ◽  
Carol A. Peterson
Keyword(s):  
Allium Cepa ◽  
Small Region ◽  
Root Tip ◽  
Radial Wall ◽  
Casparian Bands ◽  
Suberin Lamellae ◽  
Casparian Band ◽  
Apoplastic Barrier ◽  
Endodermal Cells ◽  
Suberin Lamella

The endodermal Casparian band in onion (Allium cepa L.) roots is first evident 10 mm from the apex. It occupies a small region (20–30%) in the middle of the radial wall for a distance of 70 mm from the apex. However, with the development of suberin lamellae in most cells at greater distances from the root tip, the band expands symmetrically through the wall until, at 80 mm from the root tip, it fills the entire radial wall. Passage cells overlying some xylem poles have a delayed development of suberin lamellae, and in these cells the Casparian bands remain narrow. The sensitive stain, Fluorol yellow 088, detects precursors of the suberin lamellae in the outer tangential walls of the endodermal cells. The presence of complete lamellae is indicated by Sudan red 7B staining and resistance to acid digestion. Growth of the Casparian band during suberin lamella development may play a role in maintaining the apoplastic barrier in this layer by enlarging the contact area between the band and the lamellae. Key words: Casparian band, endodermis, suberin lamella, Allium cepa.

scholarly journals Applicability of a Monolithic Column for Separation of Isoquinoline Alkalodis from Chelidonium majus Extract

Molecules ◽  
2019 ◽  
Vol 24 (19) ◽  
pp. 3612 ◽  
Author(s):  
Staniak ◽  
Wójciak-Kosior ◽  
Sowa ◽  
Strzemski ◽  
Sawicki ◽  
...  
Keyword(s):  
Monolithic Column ◽  
Gradient Elution ◽  
Root Extract ◽  
Organic Modifier ◽  
Isoquinoline Alkaloids ◽  
Chelidonium Majus ◽  
Peak Asymmetry ◽  
Application Potential ◽  
Chromatographic Plate ◽  
Chromatographic Parameters

Isoquinoline alkaloids are the main group of secondary metabolites present in Chelidonium majus extracts, and they are still the object of interest of many researchers. Therefore, the development of methods for the investigation and separation of the alkaloids is still an important task. In this work, the application potential of a silica-based monolithic column for the separation of alkaloids was assessed. The influence of the organic modifier, temperature, salt concentration, and pH of the eluent on basic chromatographic parameters such as retention, resolution between neighboring peaks, chromatographic plate numbers, and peak asymmetry were investigated. Based on the obtained results, a gradient elution program was developed and used to separate and quantitatively determine the main alkaloids in a Chelidonium majus root extract.

scholarly journals Is the Responsiveness to Light Related to the Differences in Stem Straightness among Populations of Pinus pinaster?

Plants ◽  
2019 ◽  
Vol 8 (10) ◽  
pp. 383
Author(s):  
Rosario Sierra-de-Grado ◽  
Valentín Pando ◽  
Pablo Martínez-Zurimendi ◽  
Bruno Moulia
Keyword(s):  
Cross Sections ◽  
Pinus Pinaster ◽  
Radial Growth ◽  
Wood Quality ◽  
Secondary Growth ◽  
Natural Populations ◽  
Ecological Features ◽  
Stem Straightness ◽  
One Year ◽  
Stem Curvature

Stem straightness is related to wood quality and yield. Although important genetic differences in stem straightness among the natural populations of Pinus pinaster are well established, the main drivers of these differences are not well known. Since the responses of trees to light are key ecological features that induce stem curvature, we hypothesized that populations with better straightness should exhibit lower photomorphogenetic and phototropic sensitivity. We compared three populations to identify the main processes driven by primary and secondary growth that explain their differences in response to light. One-year-old seedlings were grown under two treatments—direct sunlight and lateral light plus shade—for a period of 5 months. The length and the leaning of the stems were measured weekly. The asymmetry of radial growth and compression wood (CW) formation were analyzed in cross-sections. We found differences among the populations in photomorphogenetic and phototropic reactions. However, the population with straighter stems was not characterized by reduced sensitivity to light. Photo(gravi)tropic responses driven by primary growth and gravitropic responses driven by secondary growth explained the kinetics of the stem leaning and CW pattern. Asymmetric radial growth and CW formation did not contribute to the phototropic reactions.

Profiling of the Mechanical Properties of Ultralow-k Films Using Nanoindentation Techniques

2011 ◽  
Vol 1297 ◽  
Author(s):  
Holm Geisler ◽  
Ulrich Mayer ◽  
Matthias U. Lehr ◽  
Petra Hofmann ◽  
Hans-Juergen Engelmann
Keyword(s):  
Mechanical Properties ◽  
Cross Sections ◽  
Light Absorption ◽  
Uv Light ◽  
Lower Surface ◽  
Rear Side ◽  
Plastic Properties ◽  
Dynamic Mechanical ◽  
Reduced Modulus ◽  
Good Agreement

ABSTRACTSeveral nanoindentation techniques were applied to the surface, the reverse side and cross-sections of PECVD ultralow-k (ULK) film stacks to characterize their elasto-plastic properties quantitatively. Results showed good agreement of the reduced modulus (Er) values measured from above and on cross-sections, respectively. Er decreased by 10-22% from the upper to the lower surface of the films. This gradient suggests that UV light absorption inside the film leads to slightly reduced curing at the rear side of the films compared to the surface of the ULK layers. Both quasi-static nanoindentation and dynamic mechanical mapping showed this trend. It is demonstrated that quantitative mechanical mapping can be performed with a lateral resolution ≤ 100nm. Slight local variations of Er were detected on ULK/SiCxNy films stacked on top of Cu-low-k interconnect structures.

Formation of ssb, dsb, and Uracil in Monofilarly and Bifilarly Bromouracil-Substituted DNA Molecules

1992 ◽  
Vol 47 (3-4) ◽  
pp. 255-263
Author(s):  
Henning Menke ◽  
Wolfgang Köhnlein
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Uv Light ◽  
Linear Part ◽  
Reversed Phase ◽  
Direct Production ◽  
Significant Difference ◽  
Effect Curve ◽  
The Cross

Abstract Bifilarly BU-substituted ColE 1 plasmid and monofilarly BU-substituted M 13 phage DNA were irradiated with UV light of 313 nm. Using agarose gel electrophoresis and “reversed phase” HPLC technique ssb, dsb induction and uracil formation, respectively, could be detected in the irradiated DNA in dependence on the UV fluence. The analysis of the strandbreaks in bifilar Col E1 DNA shows a significant part of directly induced dsb. Cross sections of ssb induction from 4.1 m2/J x 107 in 28%, 3.9 m2/J x 107 in 55% and 3.1 m2/J x 107 in 8 5 -9 0% BU-substituted DNA were calculated. The cross section for dsb induction was found to be 0.04 m2/J x 107, estimated from the linear part of the fluence effect curve. In monofilar M13 DNA a linear fluence effect curve for dsb induction was obtained. Excluding other than the direct production of dsb by using an in vitro approach for M13 DNA , the results strongly support the hypothesis that dsb can be induced by one photochem ical absorption event. The cross section for ssb was 3.8 m2/J x 107 and for dsb 0.05 m2/J x 107 in 41.5% monofilarly BU-substituted M13 DNA . The comparison of ssb, dsb, and uracil production in bifilar and monofilar DNA with similar BU substitution showed no significant difference between the two DNA systems (ColE 1, M 13), indicating that the location of BU molecules in one or in both DNA strands will not lead to a different number of lesions after UV313 exposure.

scholarly journals Modulatory Effect of Chelidonium majus Extract and Its Alkaloids on LPS-Stimulated Cytokine Secretion in Human Neutrophils

Molecules ◽  
2020 ◽  
Vol 25 (4) ◽  
pp. 842 ◽  
Author(s):  
Sylwia Zielińska ◽  
Monika Ewa Czerwińska ◽  
Magdalena Dziągwa-Becker ◽  
Andrzej Dryś ◽  
Mariusz Kucharski ◽  
...  
Keyword(s):  
Biological Activities ◽  
Cytokine Secretion ◽  
Human Neutrophils ◽  
Root Extract ◽  
Dependent Manner ◽  
Chelidonium Majus ◽  
Concentration Dependent Manner ◽  
Cytotoxic Effects ◽  
Tnf Α ◽  
High Cytotoxicity

Due to certain differences in terms of molecular structure, isoquinoline alkaloids from Chelidonium majus engage in various biological activities. Apart from their well-documented antimicrobial potential, some phenanthridine and protoberberine derivatives as well as C. majus extract present with anti-inflammatory and cytotoxic effects. In this study, the LC–MS/MS method was used to determine alkaloids, phenolic acids, carboxylic acids, and hydroxybenzoic acids. We investigated five individually tested alkaloids (coptisine, berberine, chelidonine, chelerythrine, and sanguinarine) as well as C. majus root extract for their effect on the secretion of IL-1β, IL-8, and TNF-α in human polymorphonuclear leukocytes (neutrophils). Berberine, chelidonine, and chelerythrine significantly decreased the secretion of TNF-α in a concentration-dependent manner. Sanguinarine was found to be the most potent inhibitor of IL-1β secretion. However, the overproduction of IL-8 and TNF-α and a high cytotoxicity for these compounds were observed. Coptisine was highly cytotoxic and slightly decreased the secretion of the studied cytokines. The extract (1.25–12.5 μg/mL) increased cytokine secretion in a concentration-dependent manner, but an increase in cytotoxicity was also noted. The alkaloids were active at very low concentrations (0.625–2.5 μM), but their potential cytotoxic effects, except for chelidonine and chelerythrine, should not be ignored.

Suberin deposition and band plasmolysis in the corn (Zea mays L.) root exodermis

1997 ◽  
Vol 75 (7) ◽  
pp. 1188-1199 ◽  
Author(s):  
Daryl E. Enstone ◽  
Carol A. Peterson
Keyword(s):  
Zea Mays ◽  
Zea Mays L ◽  
Lateral Roots ◽  
Root Surface ◽  
Casparian Bands ◽  
Suberin Lamellae ◽  
Tight Connection ◽  
Casparian Band ◽  
Apoplastic Barrier ◽  
Suberin Lamella

The exodermal Casparian band in corn (Zea mays L.) was first seen 10 mm distal to the kernel 4 days after planting. From its inception, the band usually occupied most of the radial wall (as seen in a cross section of the root). Subsequent maturation of the band around the root was asynchronous into the region of emerging lateral roots. Thus, a continuous apoplastic barrier would have been absent over much of the young root surface. Suberin lamellae development was also asynchronous, as these structures formed in those cells which had Casparian bands. Frequently, a lamella was initially deposited in patches, progressing centripetally until a continuous lipid layer was formed around the cell protoplast. Many instances of band plasmolysis (typical of the endodermis) were observed in the developing uniform exodermis. It could occur in cells with no detectable Casparian bands, suggesting that the tight connection between the plasmalemma and the wall that causes this phenomenon is not due to hydrophobic attractions. The results are consistent with the idea that there are strong attractions between proteins of the membrane and wall in the region of the Casparian band. The tight connection between the plasmalemma and the wall was broken during the later stages of suberin lamella development. Key words: Zea mays L., Poaceae, band plasmolysis, exodermis, Casparian band, suberin lamella.

scholarly journals Sent to the Corner: xylem vessel anatomy not surface area determines megaphyll hydraulics in Cecropia obtusa Trécul (Urticaceae)

2018 ◽  
Author(s):  
Sébastien Levionnois ◽  
Sabrina Coste ◽  
Eric Nicolini ◽  
Clément Stahl ◽  
Hélène Morel ◽  
...  
Keyword(s):  
Cross Sections ◽  
Specific Conductivity ◽  
Secondary Growth ◽  
Cross Sectional ◽  
Positive Correlation ◽  
Leaf Level ◽  
Leaf Dimensions ◽  
Level Model ◽  
Primary Stem ◽  
Leaf Model

AbstractCorners rule predicts a positive correlation between leaf dimensions and the cross-sectional area of the primary stem. Although this relationship is usually explained by hydraulic and mechanical requirements, these hypotheses have never been tested empirically. However, Corner’s rule is tricky to investigate since rapid secondary growth of the stem prevents a rigorous link being established between a given leaf and the supporting stem. We chose a twig-like leaf model since petiole anatomy is only linked to the attached lamina. We tested the hypothesis that anatomical adjustments to hydraulic requirements related to vessel size enable reduced investment in tissue in the framework of Corner’s rule. We conducted a functional, mechanistic and intraspecific investigation of Cecropia obtusa Trécul, a Neotropical pioneer tree, by integrating morphological, anatomical and theoretical hydraulic traits around the lamina-petiole size relationship. The twig-like structure of the leaf and the strong lamina-petiole correlation of this model tree species made it possible to use the leaf-level model for a rigorous investigation of the functional implications of Corner’s rule. We found a positive correlation between petiole size, lamina size, the ratio of mean vessel area to vessel frequency in the petiole xylem and theoretical specific conductivity in the petiole xylem. Hydraulic function supports Corner’s rule to a lesser extent than previously thought. Variations in vessel dimensions mainly drive xylem hydraulic performances and avoid disproportionate petiole cross-sections to answer to hydraulic requirements associated with lamina size.

IV.—The Occurrence of Cell Division in the Endodermis

1931 ◽  
Vol 50 ◽  
pp. 38-50 ◽  
Author(s):  
George Bond
Keyword(s):  
Considerable Increase ◽  
Secondary Growth ◽  
Rapid Expansion ◽  
Mechanical Function ◽  
Endodermal Cell ◽  
Active Growth ◽  
Passive Stretching ◽  
Original Cell ◽  
Endodermal Cells ◽  
Suberin Lamella

Summary1. Endodermal cells frequently show considerable increase in tangential dimension at a late stage in their existence, as a result of which the continuity of the endodermis may be maintained, despite the rapid expansion of the intra-endodermal cylinder following secondary growth.2. This tangential increase in size of the endodermal cells is usually accompanied by their division. The divisions may actually cause the increase in size of the cells, that is, there is active growth of the cells. Or they may follow a passive stretching. In either case the new walls fulfil a mechanical function, lending added strength to the stretched walls of the original cell.3. Two types of division are distinguishable:(a) Those occurring in primary endodermal cells. The new walls soon develop Caspary strips, linking up with those of the parent cells.(b) Divisions in tertiary endodermal cells. The new walls here show neither Caspary strip nor suberin lamella.4. It is pointed out that in neither case does the development of new walls interfere with the impermeability of the endodermis.5. The occurrence of the divisions is considered in relation to the supposed impermeability of the suberin lamella of the secondary endodermal cell, and to the conditions resulting in the deposition of the Caspary strip.

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