Xylem Rays Research Articles

Fluid permeability in poplar tension and normal wood in relation to ray and vessel properties

The impact of ray and vessel features on the radial air permeability and liquid penetration was compared between poplar (Populus nigra) tension and normal wood. Air permeability was measured by the falling-water volume-displacement method. To measure liquid penetration, specimens were saturated with safranin solution by the full-cell process at low pressure, and the pattern of red color penetration was then examined. Results revealed no significant difference in vessel frequency, intervessel and vessel-ray pit diameter between tension and normal wood, whereas porosity and average vessel lumen area in normal wood were significantly greater than those in tension wood. Regarding rays, their length was not different between normal and tension wood, but the latter had more frequent rays per millimeter. Since xylem rays are important flow conduits in lateral movement of fluids, it could be hypothesized that a larger number of rays in tension wood would lead to improved radial permeability. However, neither air permeability nor liquid penetration varied significantly in the studied specimens. Consequently, the results proved that ray frequency has no determining role in radial fluid flow in poplar tension and normal wood and that the share of intervessel and vessel-ray pits in radial permeability is more important.

A Contribution on the Microcharacters of Barleria prionitis L. Useful in Pharmcognosy

Barleria prionitis (Acanthaceae) is an important medicinal plant distributed throughout the various regions of India and useful in urinary and paralytic affection, stomach disorders, catarrh, cough and anasaraca and lacerated sole. In the present investigation an attempt was made to study the anatomy of root, stem, lamina, midrib, petiole, stomata and trichomes as well as histochemical localization of various substances viz., calcium oxalate, lignin, suberin, lipids in the organs of Barleria prionitis. The present study revealed that the plant distinguishing microcharacters viz., bicollateral vascular bundles, internal phloem, uni - biseriate xylem rays, inverted omega shape vascular bundle, diacytic stomata and eglandular as well as glandular trichomes which are useful in solving taxonomic problems and pharmacognosy. They have significance in identification of crude drugs from this taxon.

Desarrollo Anatómico de los Meristemas y tallos de Alnus jorullensis H. B. K.

The shoot apex of Alnus jorullensis comprises two well-defined tunica layers and a corpus, which gives rise to foliar primordial and to procambial strands maturing acropetally. The primary shoot shows a eustek within abundant perenchyma consisting of isodiametric cells. Three leaf traces and three leaf gaps are seen at each node. Secondary xylem is made up of abundant, poorly lignified fiber tracheids, with apotracheal wood parenchyma, uniseriate and scantily biseriate xylem rays and apparently mucilaginous secretory cells. Vessel clements range about a mean length of 710 µm and a mean width of 70 µm with end-wall angles averaging 24° 56'. Perforation plates are scalariform, ranging fron 9 to 26 bars (Av. 16.48). In the course of the first year's growth, side-wall pitting changes from the metaxylemic reticulate-scalariform to the secondary opposite, bordered pattern.

Tissues-based chemical profiling and semi-quantitative analysis of bioactive components in the root of Salvia miltiorrhiza Bunge by using laser microdissection system combined with UPLC-q-TOF-MS.

BackgroundThe dry root of Salvia miltiorrhiza Bunge (Danshen in Chinese) is an used-widely traditional Chinese herbal medicine with and promising efficacy. This herbal plant has been extensively cultivated in China. Currently, people usually rely on its morphological features to evalaute its pharmaceutical quality. In this study, laser micro-dissection system (LMD) was applied to isolate single fresh tissue of root of S. miltiorrhiza. Under fluorescent microscopic model, five tissues namely cork, cortex, phloem, xylem ray and vessel were well recognized and isolated accurately by LMD, respectively and then the distribution pattern of the major bioactive compounds in various tissues was investigated by ultra-performance liquid chromatography-quadrupole/time of flight-mass spectrometry, which aims to validate the traditional experience on evaluating pharmaceutical quality of Danshen by morphological features.ResultsTotal 62 chemical peak signals were captured and 58 compounds including 33 tanshinones, 23 salvianolic acids and 2 others were identified or tentatively characterized in micro-dissection tissues. Further semi-quantitative analysis indicated that the bioactive components such as tanshinones and salvianolic acids were mainly enriched in cork tissue.ConclusionIn the present study, analysis of metabolic profile in different tissues of roots of S. miltiorrhiza is reported for the first time. The distribution pattern of major bioactive components could enable medicinal vendors and consumers to relatively determine the pharmaceutical quality of Danshen by morphological features.Graphical abstractTissues-based chemical profiling of DanshenElectronic supplementary materialThe online version of this article (doi:10.1186/s13065-016-0187-7) contains supplementary material, which is available to authorized users.

Development of successive cambia and wood structure in stem of Rivea hypocriteriformis (Convolvulaceae)

Abstract This study examined the formation of successive rings of cambia in Rivea hypocriteriformis Choisy (Convolvulaceae). The mature stem is composed of four to five rings of xylem alternating with phloem. Successive cambia originate as smaller and larger segments; union and anastomosing of small cambial segments often leads to the formation of discontinuous rings. In the initial stage of growth, several vascular bundles interconnect to form the first ring of vascular cambium. The cambium remains functional for one complete season and becomes dormant during summer; a new ring of cambium is completed prior to the subsequent monsoon season and sprouting of new leaves. Successive cambia are initiated from the pericyclic parenchyma situated three to four cell layers outside of the protophloem. Functionally, all the successive cambia are bidirectional and produce secondary xylem centripetally and phloem centrifugally. The secondary xylem is diffuse-porous, with indistinct growth rings and consisting of wide fibriform vessels, fibre tracheids, and axial and ray parenchyma cells. The xylem rays are uni- to multiseriate and heterocellular. The multiseriate rays contain lignified marginal ray cells and thin-walled, unlignified central cells. The central ray cells also show accumulations of starch and druses. Discrete strands of intraxylary phloem occur at the periphery of the pith, and additional intraxylary phloem develops from adjacent cells as secondary growth progresses. Earlier-formed phloem shows heavy accumulation of callose, followed by its compaction. The development of successive cambia is correlated with extension growth and with the phenology of the plant.

Do cytokinins, volatile isoprenoids and carotenoids synergically delay leaf senescence?

Do cytokinins, volatile isoprenoids and carotenoids synergically delay leaf senescence?

A Brief Review on Pharmacognosy, Phytochemistry and Therapeutic Potential ofSolanum IndiumL. used in Indian Systems of Medicine

Solanum indicum L. (Fam. Solanaceae) commonly known as poison berry in English is a prickly, much branched perennial under shrub, nearly upto 1m high, mostly found throughout India in warmer parts upto an elevation of 1500 m. This important medicinal plant is widely used in folk and traditional Indian systems of medicine for poisonous affections, skin diseases, ulcers difficult breathing, abdominal pain, cough and dyspepsia. In Ayurveda and Siddha. It is an important ingredient of dasamoola group of plants. The review attempts to highlight various available literature with respect to the therapeutic uses, enthno-medicinal uses, pharmacognostic studies, chemical constitutes and various reported pharmacological activities. Some steroidal alkaloids/glycoalkaloids such as Solasodine, Solasonine, Solamargine, Solanidine and Solanine were reported by various investigators. Pharmacognostic studies revealed the presence black powdery depositions of sandy crystals, throughout the root, sclerieds in the cortical region, phloem fibres towards the periphery and uni to biseriate medullary rays in xylem and phloem as the diagnostic characters of root of S. indicum. It is reported to have hepatoprotective, anthelmintic, antioxident and antimicrobial activity.

Study on the Retention and Distributions of the Copper-Based Preservative in Standing Tree Chinese Fir (Cunninghamia lanceolata)

In spite of some studies about the wood permeability and its improving measures, some progress has been made to study the diffusion and transmission of preservative solutions in standing trees. In the present study, copper- (Cu-) based preservative with other reagents is injected into the standing treeChinese firusing sap-flow method. The chemical compositions of the retreated woods are analyzed with Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The samples from different height positions are analyzed with scanning electron microscope (SEM) and atomic absorption spectroscopy (AAS) to obtain microstructures and preservative retention, respectively. The results indicate that the preservative solutions with lower concentrations are more conducive to diffusion and transmission in the wood. Moreover, the preservative retention at different height position has a greater concentration gradient for composite preservative solutions than those of the single preservative solutions. Solidified preservative particles are observed in xylem rays with SEM. The results of the present study provide some useful information for the functional design of the target wood products.

Accelerated solvent extraction—An efficient tool to remove extractives from tree-rings

Prior to performing stable isotope analysis in tree rings, investigators usually extract cellulose from wood samples, which represents a tedious and time-consuming task. In this experiment, two different protocols for holocellulose extraction were compared, namely the Jayme-Wise technique and the Accelerated Solvent Extractor (ASE), a relatively new device operating under high temperature and pressure. We found that both techniques are equivalent regarding resin removal, produce comparable δ13C results, do not damage the samples, and leave no resin in the xylem rays after treatment. However, the ASE is a lot less time-consuming, being ten times faster than the soxhlet based method, in addition to being safer and more convenient.

Charred wood of Prototaxoxylon from the Wuchiapingian Wutonggou Formation (Permian) of Dalongkou, northern Bogda Mountains, northwestern China

Charred wood occurs sporadically in sedimentary rocks in China. A marcroscopic charcoal with well-preserved anatomical structure is described from the Wuchiapiangian Wutonggou Formation in the southern part of Dalongkou section, northern Bogda Mountains in the Junggar Basin, northwestern China. It is characterized by uniseriate radial tracheidal pitting, taxaceous tertiary spiral thickenings in the tracheidal walls, uniseriate tangential tracheidal pitting, homogeneous, uniseriate, 2–10 cells high xylem rays, and 1–2 pits in each cross-field. It is assigned to Prototaxoxylon uniseriale Prasad. The uniseriate, bordered, contiguous, rarely separate tangential pitting of P. uniseriale is evidenced clearly for the first time. The features of this species show a close affinity with conifers. The coniferous charred wood may have been derived from an extrabasinal forest, perhaps from upland environment deep within the hinterland, according to results of modern taphonomic research.

Influence of xylem ray integrity and degree of polymerization on bending strength of beech wood decayed by Pleurotus ostreatus and Trametes versicolor

The scope of this research was to evaluate the influence of xylem ray (XR) and degree of polymerization (DP) of holocellulose in Oriental beech wood (Fagus orientalis Lipsky.) on impact bending strength against two white-rot fungi. Beech wood specimens, exposed to Pleurotus ostreatus and Trametes versicolor, were evaluated for impact bending strength at 15-day intervals for 120 days. Microscopic evaluations at each time interval indicated that both fungi degraded marginal ray parenchyma at early stages of decomposition causing a drastic loss in impact bending strength. However, the two fungi differed in their ability to reduce DP; DP and xylem ray integrity (without precedence) were the most important factors in mechanical stability of beech wood.

Relationship between Anatomical Structures of Populus euphratica and Ecoenvironment

We used light microscope,scanning electron microscope and histochemical localization techniques to study the relations between secondary vascular tissue and the ecological adaptation of Populus euphratica. P.euphratica has many structural characteristics and tuber member characteristics,which are adapt to ecological environment. The ratio of secondary phloem with developed phloem fiber to secondary xylem is 1 /7 in width,and much cells with rich protein distributed in parenchyma. Less vessels in large diameter,with thick wall and multiple-pore distributed in the wood arranged radially,as a result,the tubal complex,mainly multiple-pore,supplemented by tracheid or bundle tracheid,was formed in secondary xylem of P. euphratica'stem,while the xylem ray remained or evolved into fibrous tracheid. There are mainly pitted vessels in stem,occasionally trapeziform-pitted type,and both type vessels are very short with truncatus and leveled-perforation. The characteristics descripted above can explain the evolution and adaptation of secondary vascular tissue and tuber members of P. euphratica in a specific habitat.

Cambial domain pattern in the root and root collar of Plalanus

The grain pattern in wood and the pattern of orientation of ray splitting and uniting were studied in roots and root collar of <i>Platanus acerifolia</i>. In roots the interlocked-grain wood was observed as in the stem. An analysis of changes in xylem rays indicates that the cambial domain pattern exists and migrates upward there. In the root collar the grain in wood was straight although cambial domains were noted too. The domain pattern is characterized by relatively wide variations of the domain length and by pulsation: expanding some domains and reducing others so that it does not become manifest in the grain.

Proteomics of nitrogen remobilization in poplar bark.

Seasonal nitrogen (N) cycling in temperate deciduous trees involves the accumulation of bark storage proteins (BSPs) in phloem parenchyma and xylem ray cells. BSPs are anabolized using recycled N during autumn leaf senescence and later become a source of N during spring shoot growth as they are catabolized. Little is known about the catabolic processes involved in remobilization and reutilization of N from BSPs in trees. In this study, we used multidimensional protein identification technology (MudPIT) and spectral counting to identify protein changes that occur in the bark during BSP catabolism. A total of 4,178 proteins were identified from bark prior to and during BSP catabolism. The majority (62%) of the proteins were found during BSP catabolism, indicating extensive remodeling of the proteome during renewed shoot growth and N remobilization. Among these proteins were 30 proteases, the relative abundances of which increased during BSP catabolism. These proteases spanned a range of families including members of the papain-like cysteine proteases, serine carboxypeptidases, and aspartyl proteases. These data identify, for the first time, candidate proteases that could potentially provide hydrolase activity required for N remobilization from BSPs and provide the foundation for research to advance our knowledge of poplar N cycling.

Development of Successive Cambia and Structure of Secondary Xylem of Ipomoea Obscura (Convolvulaceae)

Abstract Stems of Ipomoea obscura Ker Gawl., increase in thickness by forming multiple rings of cambia. Stems 5-6 mm thick produce parenchymatous derivatives which divide repeatedly to form small arcs of cambium. Several such small arcs initiate simultaneously and form a ring of small cambial arcs. After the formation of a few xylem and phloem elements, all these arcs are interconnected by transdifferentiation of parenchyma cells present between the cambial arcs and constitute a complete cambial cylinder. This newly formed cambium is functionally bidirectional: earlier- formed arcs produce xylem centripetally and phloem centrifugally, while later-formed segments exclusively produce thin-walled parenchyma cells on either side. Young stems are circular in cross section but as stem thickness increases they become oval to elliptic or lobed and dumbbell-shaped. Xylem rays are mostly uni- or biseriate and thin-walled, but multiseriate rays characteristic for a climbing habit are observed occasionally. In thick stems, the marginal ray parenchyma in most of the samples becomes meristematic and develops ray cambia which exclusively produce sieve elements. Similarly, parenchyma cells produced from later-formed cambial segments give rise to several irregularly oriented vascular bundles. The secondary xylem is diffuse porous, with indistinct growth rings and is composed of fibriform and wider vessels, fibres, and axial and ray parenchyma cells, while phloem consists of sieve elements, companion cells, and axial and ray parenchyma cells.

Synchrotron X-ray micro-tomography imaging and analysis of wood degraded by Physisporinus vitreus and Xylaria longipes.

Incubation of Norway spruce with Physisporinus vitreus and sycamore with Xylaria longipes results in reduction in density of these wood species that are traditionally used for the top and bottom plate of a violin, which follows by enhanced acoustic properties. We used Synchrotron X-ray micro-tomography, to study the three-dimensional structure of wood at the micro-scale level and the alterations of the density distribution after incubation with two white-rot fungi. Micro-tomography data from wood treated at different incubation periods are analyzed and compared with untreated (control) specimens to determine the wood density map and changes at the cell-wall level. Differences between the density of early- and latewood, xylem ray and around bordered pits in both Norway spruce and sycamore are studied. Three-dimensional hyphal networks of the P.vitreus and Xylaria longipes hyphae are visualized inside the cell lumina and their significance on the density of the early- and latewood cells after different incubation periods are discussed. The study illustrates the utility of X-ray micro-tomography for both qualitative and quantitative studies of a wide variety of biological systems and due to its high sensitivity, small structural changes can be quantified.

Ougenioxylon chinjiensis sp. nov., a New Fossil Species of the Family Leguminosae from Chinji Formation Salt Range, Punjab Pakistan

This work is comprised of anatomical study of fossil wood collected from Chnji formation (72°22'E, 32°41'N) of Miocene age exposed at Chinji National Reservoir. The material consists of a single piece of petrified wood dark brown in colour. The three dimensional sections were prepared by ground thin section technique. Microscopic examination of the characters was compared with modern and fossil wood and found comparable with the family Leguminosae. The closest resemblance of our fossil wood is with the wood of Ougenia. This fossil wood shows close resemblance in respect of vessels, fibers, parenchyma and xylem rays character. Therefore it is considered as new species and it is named Ougenioxylon chienjiensis sp. nov. The specific epithet refers to Chinji formation to which fossil wood belongs.

Multiple cambia and secondary xylem of Ipomoea pes-caprae (L.) R. Br. (Convolvulaceae)

Structure of secondary xylem and pattern of secondary thickening in climbing species are different from those in self-supporting plants. In many climbing species, stem diameter increases by forming more than one ring of cambium (referred to as multiple/successive cambia), while their secondary xylem usually contains abundant parenchyma, large vessels and wide rays. In beach morning glory (Ipomoea pes-caprae (L.) R. Br., Convolvulaceae), stem thickness increases by forming multiple rings of cambia. After a short period of normal secondary growth, the first successive cambium ensues from the pericyclic parenchyma. Thereafter, subsequent cambial rings originate from parenchyma cells produced initially by the previous cambium. In stems that are 15–20 mm thick, parenchymal cells produced by the initial activity of the previous cambia become meristematic and form small arcs of functionally inverse cambia that produce secondary xylem centrifugally and secondary phloem centripetally. Unequal production of secondary xylem by these cambia gives the stem various shapes other than cylindrical. Besides successive cambia, some cambial variants also develop in the stem which are: (1) irregularly distributed patches of thin-walled xylem parenchyma becoming meristematic and differentiating into interxylary phloem islands; (2) xylem ray cells acquiring meristematic character and behaving like cambium (referred to as ray cambium); and (3) in thick stems, internal cambium deriving from marginal pith cells, which are functionally bidirectional and producing secondary xylem centripetally and phloem centrifugally. Structure and development of successive cambia, ray cambia and internal cambium are discussed here.

A Ranunculalean Liana Stem from the Cretaceous of British Columbia, Canada:Atli moriniigen. et sp. nov.

Premise of research. The lianoid habit is found in 125 extant plant families and is most diverse and abundant in structurally complex forests, such as tropical forests. A stem with lianoid anatomy is described from Cretaceous sediments of Hornby Island, British Columbia.Methodology. The stem segment, 2.5 cm in diameter and 2.8 cm long, was studied using the cellulose acetate peel technique and SEM. Anatomy was documented and compared to fossil and modern taxa.Pivotal results. The stem lacks distinct growth increments, and the fibrous wood is dissected by large (>10 cells wide) rays. Wood is diffuse porous with mostly solitary vessels, rarely in tangential multiples (2–4). Vessel elements have a mean tangential diameter of 198 μm and mean length of 527 μm, bearing medium to large, crowded, elliptical to flat-elliptical alternate pits. Axial parenchyma is diffuse and vessels are surrounded by vasicentric tracheids with alternate bordered pitting. Rays are homocellular and >2 cm tall. Phloem rays are dilated, protruding into the xylem rays; thick-walled ray cells contain prismatic crystals. Periderm is composed of thin-walled cells interspersed with sclerotic nests. Wood anatomy of the fossil shows the most similarity to that of lianas in the Menispermaceae, Lardizabalaceae, and Ranunculaceae.Conclusions. The Hornby Island stem represents a new taxon, Atli morinii gen. et sp. nov. (Ranunculales). This liana specimen expands our knowledge of Cretaceous biodiversity and points to the presence of structurally complex forests on Hornby Island in the Campanian. Anatomy of Atli and other Cretaceous liana stems combines characteristics of several families in Ranunculales, documenting past anatomical diversity and possible stem lineage mosaicism. The most diverse lianoid lineages currently known from the Cretaceous and Paleogene are early-divergent eudicots, particularly Ranunculales and Vitales that account for more than 50% of described lianoid species during this key time period of angiosperm diversification.

New gymnospermous woods from the Permian of the Parnaíba Basin, Northeastern Brazil, Part I: Ductoabietoxylon, Scleroabietoxylon and Parnaiboxylon

The Permian permineralized flora of the Parnaíba Basin, NE Brazil, has been studied since 1872, when the first fossil fern was described from this region. Since then, many fossil pteridophytes have been collected and studied; however, the gymnosperms are still little known. The present contribution focuses on the study of gymnospermous woods from the Motuca Formation. This study presents four new taxa of which three are formally described: Ductoabietoxylon solis gen. et sp. nov., Scleroabietoxylon chordas gen. et sp. nov., Parnaiboxylon rohnae gen. et sp. nov. and Parnaiboxylon sp. 1. The first two genera share an outstanding feature: the presence of abietinoid pitting, a rare characteristic among fossil woods, and a derived stage in the evolution of xylem rays. The presence of several new genera and species in the lowermost Motuca Formation reveals the richness and importance of this area for paleobotanical studies.