Diffusion Pathways for Heartwood Substances in Acacia Mangium

IAWA Journal ◽  
2009 ◽  
Vol 30 (1) ◽  
pp. 37-48 ◽  
Author(s):  
Chunhua Zhang ◽  
Hisashi Abe ◽  
Yuzou Sano ◽  
Takeshi Fujiwara ◽  
Minoru Fujita ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Acacia Mangium ◽  
Intercellular Spaces ◽  
Structural Variations ◽  
Axial Parenchyma ◽  
Dimensional Network ◽  
Parenchyma Cells ◽  
Resin Cast ◽  
Ray Parenchyma ◽  
Ray Parenchyma Cells

The cellular distribution of heartwood substances and the structure of the pathways for their diffusion were studied in Acacia mangium Willd. Apart from ray parenchyma cells, axial parenchyma cells also are involved in the formation of heartwood substances. Heartwood substances were unevenly distributed in the heartwood. A closer inspection of interfibre pit pairs revealed that, although many pit membranes were completely covered with encrusting materials, some pit pairs had many small openings on their pit membranes. The openings possibly function as intercellular diffusion pathways for heartwood substances. The sizes of the pits varied considerably, ranging from 0.4 to 2.3 μm in diameter. These structural variations in the interfiber pits might be one of the factors contributing to the uneven distribution of the heartwood substances. A large number of blind pits were present in the ray parenchyma cells and faced the intercellular spaces, into which heartwood substances from the ray parenchyma cells were released via these blind pits. Resin-cast replicas demonstrated that the intercellular spaces and the blind pits formed a three-dimensional network that is considered to serve as an extracellular diffusion pathway for heartwood substances.

Extracellular diffusion pathway for heartwood substances in Albizia julibrissin Durazz.

Holzforschung ◽  
2004 ◽  
Vol 58 (5) ◽  
pp. 495-500 ◽  
Author(s):  
Chunhua Zhang ◽  
Minoru Fujita ◽  
Keiji Takabe
Keyword(s):  
Wood Fiber ◽  
Three Dimensional ◽  
Cellular Distribution ◽  
Intercellular Spaces ◽  
Albizia Julibrissin ◽  
Diffusion Pathway ◽  
Dimensional Network ◽  
Parenchyma Cells ◽  
Ray Parenchyma ◽  
Ray Parenchyma Cells

Abstract A three-dimensional network of intercellular spaces, deemed an extracellular diffusion pathway for heartwood substances, was detected in Albizia julibrissin. Electron microscopy revealed a large number of blind pits in ray parenchyma cells, most facing intercellular spaces. Heartwood substances, which are synthesized in the ray parenchyma cells, are released not only into neighboring cells through pit pairs, but also into the intercellular spaces through the blind pits. There were two types of wood fiber in the heartwood region: one with a lumen surface lined with heartwood substances and one that lacked such lining on its lumen surface. This finding supports the observation that the cellular distribution of heartwood substances is not homogenous throughout the heartwood. There was no positive correlation, however, between this uneven distribution and the distance of a wood fiber from the ray.

scholarly journals How Long Do Wood Parenchyma Cells Live in the Stem of a Scots Pine (Pinus sylvestris L.)? Studies on Cell Nuclei Status along the Radial and Longitudinal Stem Axes

Forests ◽  
2019 ◽  
Vol 10 (11) ◽  
pp. 977 ◽  
Author(s):  
Mirela Tulik ◽  
Joanna Jura-Morawiec ◽  
Anna Bieniasz ◽  
Katarzyna Marciszewska
Keyword(s):  
Pinus Sylvestris ◽  
Scots Pine ◽  
Apical Meristem ◽  
Uv Light ◽  
Cell Nuclei ◽  
Growth Rings ◽  
Axial Parenchyma ◽  
Parenchyma Cells ◽  
Ray Parenchyma ◽  
Ray Parenchyma Cells

This paper deals with the spatial distribution of heartwood in Scots pine stems (Pinus sylvestris L.), determined on the basis of the absence of nuclei in parenchyma cells. Samples were collected at several heights from two Scots pine stems growing in fresh coniferous stand as codominant trees. Transverse and radial sections were cut from the samples and stained with acetocarmine to detect the nuclei and with I2KI to show starch grains. Unstained sections were also observed under ultraviolet (UV) light to reveal cell wall lignification. The shapes of the nuclei in ray and axial parenchyma cells differed: the axial parenchyma cells had rounded nuclei, while the nuclei of the ray parenchyma cells were elongated. The lifespan of the parenchyma cells was found to be 16–42 years; the longest-lived were cells from the base of the stem, and the shortest-lived were from the base of the crown. The largest number of growth rings comprising heartwood was observed at a height of 1.3–3.3 m, which signifies that the distribution of heartwood within the stem is uneven. Moreover, the distance of the cells from the apical meristem and the cambium was seen to have an effect on the presence of living parenchyma cells, i.e., those with stained nuclei.

Wood Anatomy Of The Genus Abies A Review

IAWA Journal ◽  
2009 ◽  
Vol 30 (3) ◽  
pp. 231-245 ◽  
Author(s):  
Luis García Esteban ◽  
Paloma de Palacios ◽  
Francisco García Fernández ◽  
Ruth Moreno
Keyword(s):  
Wood Anatomy ◽  
Single Cells ◽  
The Other ◽  
Axial Parenchyma ◽  
Interspecific Differences ◽  
Parenchyma Cells ◽  
Ray Parenchyma ◽  
Ray Cells ◽  
Ray Parenchyma Cells ◽  
Resin Canals

The literature on the wood anatomy of the genus Abies is reviewed and discussed, and complemented with a detailed study of 33 species, 1 subspecies and 4 varieties. In general, the species studied do not show diagnostic interspecific differences, although it is possible to establish differences between groups of species using certain quantitative and qualitative features.The marginal axial parenchyma consisting of single cells and the ray parenchyma cells with distinctly pitted horizontal walls, nodular end walls and presence of indentures are constant for the genus, although these features also occur in the other genera of the Abietoideae. The absence of ray tracheids in Abies can be used to distinguish it from Cedrus and Tsuga, and the irregularly shaped parenchymatous marginal ray cells are only shared with Cedrus. The absence of resin canals enables Abies to be distinguished from very closely related genera such as Keteleeria and Nothotsuga. The crystals in the ray cells, taxodioid cross-field pitting and the warty layer in the tracheids can be regarded as diagnostic generic features.

scholarly journals Comparative Wood Anatomy in Pinaceae with Reference to Its Systematic Position

Forests ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1706
Author(s):  
Luis García Esteban ◽  
Paloma de Palacios ◽  
Alberto García-Iruela ◽  
Francisco García-Fernández ◽  
Lydia García-Esteban ◽  
...  
Keyword(s):  
Molecular Phylogeny ◽  
Wood Anatomy ◽  
Systematic Position ◽  
Axial Parenchyma ◽  
The Family ◽  
Parenchyma Cells ◽  
Ray Parenchyma ◽  
Ray Parenchyma Cells ◽  
Resin Canals ◽  
Comparative Wood Anatomy

The wood anatomy of 132 species of the genera Abies, Cathaya, Cedrus, Keteleeria, Larix, Nothotsuga, Picea, Pinus, Pseudolarix, Pseudotsuga and Tsuga was studied to determine the elements that characterise the xylem of each genus and discuss possible groupings by wood anatomy for comparison with clades established by molecular phylogeny. The presence of resin canals and ray tracheids supports the family Pinaceae, although the absence of ray tracheids in Keteleeria and their occasional presence in Abies and Pseudolarix weakens it. Based on wood structure, Pinaceae clearly supports division into two groups, coinciding with molecular phylogeny: Pinoideae (Cathaya-Larix-Picea-Pinus-Pseudotsuga) and Abietoideae (Abies-Cedrus-Keteleeria-Nothotsuga-Pseudolarix-Tsuga). Although differences between genera are slight in Pinoideae, the Abietoideae group presents problems such as the presence of only axial resin canals in Keteleeria and Nothotsuga, absence of ray tracheids in Keteleeria and presence of traumatic radial resin canals in Cedrus. However, other features such as pitted horizontal walls and nodular end walls of ray parenchyma cells, indentures, scarce marginal axial parenchyma and presence of crystals in ray parenchyma strengthen the Abietoideae group.

Ray Structure Differences between Rootwood and Stemwood in a Range of Softwood Species

IAWA Journal ◽  
2009 ◽  
Vol 30 (1) ◽  
pp. 71-80 ◽  
Author(s):  
Pat Denne ◽  
Siân Turner
Keyword(s):  
Parenchyma Cells ◽  
Ray Parenchyma ◽  
Structural Differences ◽  
Ray Parenchyma Cells ◽  
Practical Implications ◽  
Softwood Species

Differences between the ray structure of rootwood and stemwood were analysed in 11 species from 5 families of gymnosperms. Rootwood was consistently found to have fewer ray tracheids, with ray parenchyma cells which were taller axially, wider tangentially, but shorter radially, and had more pits per cross-field than stemwood. A scale for quantifying types of cross-field pitting is proposed, and statistically significant differences in type and diameter of cross-field pitting were found between rootwood and stemwood of most species sampled. These structural differences have practical implications for identification of gymnosperm roots, and for distinguishing between rootwood and stemwood.

Ray Structure in Root- and Stem-Wood of Larix Decidua: Implications for Root Identification and Function

IAWA Journal ◽  
2008 ◽  
Vol 29 (1) ◽  
pp. 17-23 ◽  
Author(s):  
Pat Denne ◽  
Peter Gasson
Keyword(s):  
Wood Anatomy ◽  
Larix Decidua ◽  
Stem Wood ◽  
Parenchyma Cells ◽  
Ray Parenchyma ◽  
Ray Parenchyma Cells ◽  
And Function

Differences in ray structure between root- and stem-wood of softwoods can cause confusion in identifying roots using keys based on stem-wood anatomy. Comparison of root- and stem-wood rays of Larix decidua showed root-wood had fewer ray tracheids, taller, wider but shorter ray parenchyma cells, and larger cross-field pits than stem-wood. The implications of these differences are considered in relation to the identification and function of roots.

INHIBITION OF WATER CONDUCTIVITY CAUSED BY WATERMARK DISEASE IN SALIX SACHALINENSIS

IAWA Journal ◽  
2000 ◽  
Vol 21 (1) ◽  
pp. 49-60 ◽  
Author(s):  
Yasuaki Sakamoto ◽  
Yuzou Sano
Keyword(s):  
Wood Anatomy ◽  
High Moisture ◽  
Water Conductivity ◽  
X Ray ◽  
Salix Sachalinensis ◽  
Water Conduction ◽  
Parenchyma Cells ◽  
Ray Parenchyma ◽  
High Moisture Level ◽  
Ray Parenchyma Cells

Water conduction and wood anatomy of Salix sachalinensis attacked by watermark disease were investigated. The internal symptom, the watermark, appeared as a brown to brown-black stained zone in sapwood. Dye injection tests revealed that water conduction did not take place in the watermark. However, soft X-ray photography and cryo-scanning electron microscopy revealed that the watermark had a high moisture level. In the watermark, some of the vessels were plugged with tyloses and masses of bacteria, and some of the ray parenchyma cells caused necrosis. Hence, the non-conductive watermark in sapwood can be considered similar to discoloured wood or wetwood.

The fine structure of the pits of Eucalyptus regnans (F. Muell.) and their relation to the movement of liquids into the wood

1960 ◽  
Vol 8 (1) ◽  
pp. 51 ◽  
Author(s):  
J Cronshaw
Keyword(s):  
Secondary Wall ◽  
Structural Features ◽  
Cellulose Microfibrils ◽  
Primary Wall ◽  
Detailed Structure ◽  
Eucalyptus Regnans ◽  
Pit Membrane ◽  
Parenchyma Cells ◽  
Ray Parenchyma ◽  
Ray Parenchyma Cells

Observstion in the electron microscope of carbon replicas of the pits of vessels, ray parenchyma cells, fibres, and tracheids of Eucalyptus regnans has shown the detailed structure of the pit borders and the pit closing membranes. In all cases in the mature wood the primary wall is left apparently without modification as the pit membrane. Unlike the borders of the pits of fibre tracheids and tracheids, the pit borders of the vessels are not separate; the cellulose microfibrils of a border may be common to several pits. The pit borders of fibre traoheids and tracheids are developed as separate entities and have a structure similar to the pit borders of softwood tracheids. The structure of the secondary wall layers associated with the pits is described and related to the structure of the pits. The fine structural features of the pits, especially of the pit closing membranes, are discussed in relation to the movement of liquids into wood.

Silica in Woody Stems

1974 ◽  
Vol 22 (2) ◽  
pp. 211 ◽  
Author(s):  
G Scurfield ◽  
CA Anderson ◽  
ER Segnit
Keyword(s):  
The Other ◽  
X Ray Diffraction ◽  
Xylem Parenchyma ◽  
X Ray ◽  
Woody Perennial ◽  
Internal Surfaces ◽  
Parenchyma Cells ◽  
Ray Parenchyma ◽  
Ray Parenchyma Cells ◽  
Scanning Electron

Scanning electron microscopy has been used to examine silica isolated by chemical means from the wood of 32 species of woody perennial. The silica consists of aggregate grains lying free in the lumina or in ray and xylem parenchyma cells in 24 of the species. It occurs as dense silica in the other species, filling the lumina or lining the internal surfaces of vessels (and fibres) in all cases except Gynotroches axillaris where it is deposited in ray parenchyma cells. Infrared spectra and X-ray diffraction diagrams, obtained for specimens of both sorts of silica, are indistinguishable from those for amorphous silica. Aggregate grain and dense silicas are also alike in that their differential thermal analysis curves show a rather broad endothermic peak between 175° and 205°C. The results are discussed in relation to possible modes of deposition of the two sorts of silica and the tendency for silica in ray parenchyma cells to be associated with polyphenols.

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