An ultrastructural study of acid phosphatase localization in Phaseolus vulgaris xylem by the use of an azo-dye method

1975 ◽  
Vol 19 (3) ◽  
pp. 543-561
Author(s):  
I. Charvat ◽  
K. Esau

The localization of acid phosphatase during xylem development has been examined in the bean, Phaseolus vulgaris. The azo dye, the final reaction product, is initially prominent in the dictyosomes, vesicles apparently participating in secondary wall formation, and in the middle lamella of the young vessel element. Final reaction particles are also present in mitochondria, chloroplasts, and certain vacuoles and are sparsely scattered in the cytoplasm. At a later stage of vessel differentiation, the azo dye is concentrated in the disintegrating cytoplasm and along the fibrils of the partially hydrolysed primary wall and middle lamella. In the mature vessel element, the azo dye is still present along the disintegrated primary wall at the side of the vessel and covers the secondary wall. In the parenchyma cell adjacent to the vessel element, acid phosphatase localization is found in the dictyosomes, endoplasmic reticulum, mitochondria, small vacuoles, and the middle lamella. The controls from all stages of vessel element development were free of azo dye particles. The concentration of acid phosphatase along the secondary walls of the mature vessels and in the middle lamella between other cells indicates that this enzyme has other functions besides autolysis of the cytoplasm and primary cell wall. Acid phosphatase may participate in the formation of the secondary wall and may also have a role in the secretion and transport of sugars.

2011 ◽  
Vol 33 (2) ◽  
pp. 14-19
Author(s):  
Stephen C. Fry ◽  
Lenka Franková ◽  
Dimitra Chormova

Mature plant cells typically have two-layered walls: a first-formed thin outer primary wall layer enclosing a later-formed thick inner secondary wall. The surface area of the primary wall limits the size of the cell and thus the maximum amount of biomass that can potentially be accumulated in the secondary wall. By controlling the shape and size of the cell, the primary wall therefore imposes the limits on the amount of inedible biofuel a plant cell can make.


2011 ◽  
Vol 236-238 ◽  
pp. 1746-1751 ◽  
Author(s):  
Kun Liang ◽  
Guan Ben Du ◽  
Omid Hosseinaei ◽  
Si Qun Wang ◽  
Hui Wang

To find out the penetration of PF into the wood cell wall and its effects onthe mechanical properties in the cellular level, the elastic modulus and hardness of secondary wall (S2layer) and compound corner middle lamella (CCML) near PF bond line region were determined by nanoindentation. Compare to the reference cell walls (unaffected by PF), PF penetration into the wood tissues showed improved elastic modulus and hardness. And the mechanical properties decreased slowly with the increasing the distance from the bond line, which are attributed to the effects of PF penetration into S2layer and CCML. The reduced elastic modulus variations were from18.8 to 14.4 GPa for S2layer, and from10.1 to 7.65 GPa for CCML. The hardness was from 0.67 to 0.52 GPa for S2layer, and from 0.65 to 0.52 GPa for CCML. In each test viewpoint place, the average hardness of CCML was almost as high as that of S2layer, but the reduced elastic modulus was about 50% less than that of S2layer. But the increase ratio of mechanical properties was close. All the results showed PF penetrates into the CCML. The penetration behavior and penetration depth from bond line were similar in both S2layer and CCML.


IAWA Journal ◽  
1996 ◽  
Vol 17 (4) ◽  
pp. 431-444 ◽  
Author(s):  
Mitsuo Suzuki ◽  
Kiyotsugu Yoda ◽  
Hitoshi Suzuki

Initiation of vessel formation and vessel maturation indicated by secondary wall deposition have been compared in eleven deciduous broadleaved tree species. In ring-porous species the first vessel element formation in the current growth ring was initiated two to six weeks prior to the onset of leaf expansion, and secondary wall deposition on the vessel elements was completed from one week before to three weeks after leaf expansion. In diffuse-porous species, the first vessel element formation was initiated two to seven weeks after the onset of leaf expansion, and secondary wall deposition was completed four to nine weeks after leaf expansion. These results suggest that early maturation of the first vessel elements in the ring-porous species will serve for water conduction in early spring. On the contrary, the late maturation of the first vessel elements in the diffuse-porous species indicates that no new functional vessels exist at the time of the leaf expansion.


1968 ◽  
Vol 16 (2) ◽  
pp. 177 ◽  
Author(s):  
A Mahmood

The use of the term cambium, or equivalent terms, in modern literature is discussed. The term cambial zone adopted in this paper includes the cambial initial and the dividing and enlarging cells. The tissue mother cell produced at each division of the initial produces a group of four cells in xylem or two cells in phloem. Theoretical constructs have been made for xylem and phloem production by associating the concepts that xylem and phloem are produced in alternate series of initial divisions and that a new primary wall is deposited around each daughter protoplast at each cell division. Correlations are derived from the theoretical constructs for the thickness of primary wall layers lying in the tangential direction and of those lying in the radial direction at progressive histological levels. Deductions from theoretical constructs are made when the initial is producing xylem, when it changes its polarity from xylem to phloem production, and when the reverse change occurs. Most of the theoretical deductions are supported by photographic evidence. The chief point of this study is the demonstration of generations (multiplicity) of primary parental walls. The term intercellular material proposed in this paper includes the cell plate plus any remnants of ancestral primary walls between the current primary walls surrounding the adjacent protoplasts. This term is still applicable to cells where secondary wall deposition is taking place or has been completed.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Lin Zheng ◽  
Jixiu Yang ◽  
Yajuan Chen ◽  
Liping Ding ◽  
Jianhua Wei ◽  
...  

Abstract Background Forest trees have important economic and ecological value. As a model tree, poplar has played a significant role in elucidating the molecular mechanisms underlying tree biology. However, a lack of mutant libraries and time-consuming stable genetic transformation processes severely limit progress into the functional characterization of poplar genes. A convenient and fast transient transformation method is therefore needed to enhance progress on functional genomics in poplar. Methods A total of 11 poplar clones were screened for amenability to syringe infiltration. Syringe infiltration was performed on the lower side of the leaves of young soil-grown plants. Transient expression was evaluated by visualizing the reporters β-glucuronidase (GUS) and green fluorescent protein (GFP). The experimental parameters of the syringe agroinfiltration were optimized based on the expression levels of the reporter luciferase (LUC). Stably transformed plants were regenerated from transiently transformed leaf explants through callus-induced organogenesis. The functions of Populus genes in secondary cell wall-thickening were characterized by visualizing lignin deposition therein after staining with basic fuchsin. Results We greatly improved the transient transformation efficiency of syringe Agrobacterium infiltration in poplar through screening for a suitable poplar clone from a variety of clones and optimizing the syringe infiltration procedure. The selected poplar clone, Populus davidiana × P. bolleana, is amenable to Agrobacterium syringe infiltration, as indicated by the easy diffusion of the bacterial suspension inside the leaf tissues. Using this technique, we localized a variety of poplar proteins in specific intracellular organelles and illustrated the protein–protein and protein–DNA interactions. The transiently transformed leaves could be used to generate stably transformed plants with high efficiency through callus induction and differentiation processes. Furthermore, transdifferentiation of the protoxylem-like vessel element and ectopic secondary wall thickening were induced in the agroinfiltrated leaves via the transient overexpression of genes associated with secondary wall formation. Conclusions The application of P. davidiana × P. bolleana in Agrobacterium syringe infiltration provides a foundation for the rapid and high-throughput functional characterization of Populus genes in intact poplar plants, including those involved in wood formation, and provides an effective alternative to Populus stable genetic transformation.


1988 ◽  
Vol 66 (10) ◽  
pp. 2038-2047 ◽  
Author(s):  
R. Howard Berg ◽  
Lorraine McDowell

Development of the wall of infected cells in Casuarina actinorhizae differs from that of many actinorhizae. After the endophyte penetrates the wall of a cortical cell, that (primary) cell wall becomes lignified, based on histochemical (autofluorescence, phloroglucinol staining) and cytochemical (permanganate staining, enzyme etching) evidence. Subsequently, the remaining walls of the infected cell become lignified. Adjacent noninfected cells somehow are stimulated to deposit a lignified secondary wall only on those walls bordering the infected cell. This remarkable participation of all adjacent noninfected cells in the development of a given infected cell results in an increased thickness and strength of the wall material surrounding infected cells. When they mature, there is a further modification of some of the wall layers surrounding infected cells, manifested in a relative impermeability to en bloc staining with permanganate. Unlike lignified walls, the permanganate-impermeable region is selectively stained by osmium or ferricyanide-reduced osmium and is relatively resistant to concentrated chromic acid digestion. A region that remains permeable to (and stained by) permanganate (part of the secondary wall of bordering noninfected cells) may be developmentally related to phi thickenings. An earlier contention that the permanganate-impermeable region contains suberin is unconfirmed. This region is most likely an unusual lignin modification or results from unidentified material impregnated in its ligninlike matrix.


1975 ◽  
Vol 19 (2) ◽  
pp. 239-259
Author(s):  
J.C. Roland ◽  
B. Vian ◽  
D. Reis

Ultracryotomy with negative staining and cytochemistry (periodic acid - thiocarbohydrazide - silver proteinate test for polysaccharides, in conjunction with mild extractions) were used to study the architecture of the cell wall and its modifications during expansion. Those techniques were applied to the study in situ of the walls of actively elongating parenchyma of mung bean (Phaseolus aureus), and pea (Pisum sativum) root and of collenchyma of celery (Apium graveolens) petioles. These complementary techniques provide information on the 3-dimensional disposition and fine structure of the subunits of the wall. In all the examples examined, the bulk of growing primary wall appears well-ordered and no progressive evolution from a transverse texture near the plasmalemma to a scattered texture near the middle lamella was observed. It seems unlikely that the development of the wall structure in relation to growth could be explained mechanically by a passive shift of the fibrillar elements in response to cellular stress. There is no evidence for an inert change in fibrillar orientation in the major part of the wall. If such occurs the process is limited to the outermost and senescent part of the wall. Thus, the texture observed does not agree with the classical multinet growth hypothesis but rather with the idea of an ordered structure of the primary wall. With the latter, the components should be able to respond in different ways to specific growth regulators and other environmental signals and thus exert a more positive control over the processes of oriented cell growth.


Weed Science ◽  
1974 ◽  
Vol 22 (3) ◽  
pp. 280-284 ◽  
Author(s):  
W. E. Robnett ◽  
P. R. Morey

Application of the ethylene-releasing agent ethephon (2-chloroethylphosphonic acid) as a lanolin paste to stems of honey mesquite [Prosopis juliflora(Swartz) DC. var.glandulosa(Torr.) Cockrell] caused the development of abnormal periderm, cortical, and xylem tissues in a localized portion of the stem within 1 cm of the treatment site. Ethephon inhibited secondary wall deposition in xylem parenchyma cells, whereas normal vessel element differentiation was unaffected. Similar changes in xylem formation occur in ethephon-treated huisache [Acacia farnesiana(L.) Willd.]. Ethephon and 2,4,5-T [(2,4,5-trichlorophenoxy)acetic acid] applied separately to honey mesquite and huisache stems have similar inhibitory effects on parenchyma cell differentiation but differ markedly in their effects on vessel element formation.


Holzforschung ◽  
2001 ◽  
Vol 55 (4) ◽  
pp. 379-385 ◽  
Author(s):  
Lloyd Donaldson ◽  
Jamie Hague ◽  
Rebecca Snell

Summary Lignin distribution was determined by interference microscopy, and by confocal laser scanning microscopy (CLSM) for a range of agricultural residues including coppice poplar, linseed, and wheat straw. Interference microscopy was used to determine the lignin concentration in the middle lamella at the cell corner, and for the secondary wall of libriform fibres in the secondary xylem of poplar and linseed. Wheat was examined in the same way for cortical fibres. In addition the secondary wall of vessel elements was examined for poplar. Confocal microscopy was used to confirm the results from interference microscopy by providing semiquantitative information based on lignin autofluorescence, and by staining with acriflavine. Wheat had the lowest level of lignification, with 31 % lignin in the middle lamella of cortical fibres and 9% lignin in the secondary wall. Poplar had a lignin concentration of 63% in the middle lamella and 6% in the secondary wall of libriform fibres, while linseed had corresponding values of 69 % and 13 %. The secondary wall of poplar vessel elements had a lignin concentration of 25 %. In all three species most of the stem tissue was lignified except for phloem and bark, where present. In linseed the pith was unlignified. In wheat, most of the parenchyma cells were lignified except for a few cells lining the stem cavity. Libriform fibres in poplar and linseed sometimes had an unlignified gelatinous layer in samples containing tension wood. In linseed, lignification was greater in xylem fibres compared to bast fibres. Ray parenchyma cells of poplar and linseed appeared to be lignified to the same extent as xylem fibres.


Sign in / Sign up

Export Citation Format

Share Document