resin canals
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Forests ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1706
Author(s):  
Luis García Esteban ◽  
Paloma de Palacios ◽  
Alberto García-Iruela ◽  
Francisco García-Fernández ◽  
Lydia García-Esteban ◽  
...  

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.


2021 ◽  
Vol 948 (1) ◽  
pp. 012002
Author(s):  
Y I Mandang ◽  
Andianto ◽  
H Oktariani

Abstract Indonesia is a country which has plants species diversity. The form of ancient plants that grew in the past are recorded as fossil woods. Several fossil woods from regions in Indonesia were collected and became exhibition collections at the Bandung Geological Museum. These fossil woods on display requires biology identity to provide more information to visitors. Identification of species of fossil woods were carried out based on the anatomical features on the smoothed cross-section. Observations were carried out by a loop hand (a magnification of 10 times and a digital loop (with a magnification of 16 times). The fossil woods anatomy features observed included vessel cells, parenchyma cells, rays cells, and the presence of resin channels. The fossil specimen which had unclear anatomy features compared by detailed description of wood anatomy available at the library and collections of wood samples owned by the Xylarium Bogoriense. The fossil woods species are Canarioxylon sp., Terminalioxylon sp., Anisopteroxylon sp., Dipterocarpoxylon sp., Dryobalanoxylon sp., Hopenium/Hopeoxylon sp., Shoreoxylon sp., Kompassioxylon sp., and Xanthophyllum sp. The mostly fossil woods species resvectively belonging to the Dipterocarpaceae, Combretaceae, Polygalaceae, Burseraceae, and Leguminosae. The fossil woods member of Dipterocarpaceae family are conspicuously characterized with the presence of resin canals.


2021 ◽  
pp. 105065
Author(s):  
Cosme F. Rombola ◽  
Carlos D. Greppi ◽  
Roberto R. Pujana ◽  
Juan L. García Massini ◽  
Eduardo S. Bellosi ◽  
...  

2021 ◽  
Vol 45 (1) ◽  
Author(s):  
Engy M. Kataia ◽  
Mohamed Mokhtar Nagy ◽  
Mohamed M. Kataia ◽  
Hala Fayek Khalil

Abstract Background This study aimed at assessing the effect of different kinematics as well as different instrument designs on efficiency of cutting of two heat-treated nickel–titanium systems. Forty resin canals with 30°-angle of curvature and a length of 16 mm were utilized in this research. They were divided into four groups depending on the instrument and the operating kinematic, group I; Azure rotary system in rotation motion, group II; Azure rotary system in Reciprocation motion, group III; Fanta AF One rotary system in rotation motion and group IV; Fanta AF One rotary system in reciprocation motion. Blocks were labeled and then weighed pre- and post-preparation with delta weight (Δ wt = wt pre − wt post) and data were documented for statistics evaluation. Results Resin canals prepared using Fanta AF One rotary system showed significantly higher weight loss than Azure rotary system in both rotation and reciprocation (P < 0.001). Insignificant difference was reported for rotation and reciprocation movements in both file systems. Conclusion The instrument’s cross section revealed a more significant impact on cutting efficiency than the motion used.


Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2283
Author(s):  
H. Yu ◽  
J. K. Holopainen ◽  
M. Kivimäenpää ◽  
A. Virtanen ◽  
J. D. Blande

Compared to most other forest ecosystems, circumpolar boreal and subarctic forests have few tree species, and are prone to mass outbreaks of herbivorous insects. A short growing season with long days allows rapid plant growth, which will be stimulated by predicted warming of polar areas. Emissions of biogenic volatile organic compounds (BVOC) from soil and vegetation could be substantial on sunny and warm days and biotic stress may accelerate emission rates. In the atmosphere, BVOCs are involved in various gas-phase chemical reactions within and above forest canopies. Importantly, the oxidation of BVOCs leads to secondary organic aerosol (SOA) formation. SOA particles scatter and absorb solar radiation and grow to form cloud condensation nuclei (CCN) and participate in cloud formation. Through BVOC and moisture release and SOA formation and condensation processes, vegetation has the capacity to affect the abiotic environment at the ecosystem scale. Recent BVOC literature indicates that both temperature and herbivory have a major impact on BVOC emissions released by woody species. Boreal conifer forest is the largest terrestrial biome and could be one of the largest sources of biogenic mono- and sesquiterpene emissions due to the capacity of conifer trees to store terpene-rich resins in resin canals above and belowground. Elevated temperature promotes increased diffusion of BVOCs from resin stores. Moreover, insect damage can break resin canals in needles, bark, and xylem and cause distinctive bursts of BVOCs during outbreaks. In the subarctic, mountain birch forests have cyclic outbreaks of Geometrid moths. During outbreaks, trees are often completely defoliated leading to an absence of BVOC-emitting foliage. However, in the years following an outbreak there is extended shoot growth, a greater number of leaves, and greater density of glandular trichomes that store BVOCs. This can lead to a delayed chemical defense response resulting in the highest BVOC emission rates from subarctic forest in the 1–3 years after an insect outbreak. Climate change is expected to increase insect outbreaks at high latitudes due to warmer seasons and arrivals of invasive herbivore species. Increased BVOC emission will affect tropospheric ozone (O3) formation and O3 induced oxidation of BVOCs. Herbivore-induced BVOC emissions from deciduous and coniferous trees are also likely to increase the formation rate of SOA and further growth of the particles in the atmosphere. Field experiments measuring the BVOC emission rates, SOA formation rate and particle concentrations within and above the herbivore attacked forest stands are still urgently needed.


IAWA Journal ◽  
2021 ◽  
pp. 1-7
Author(s):  
Anna V. Stepanova ◽  
Nataliya A. Vasilyeva

Abstract Wood identification of 13 samples is made for the first time for the well-preserved coffin from the Bosporan Kingdom exhibited in the State Hermitage Museum. Due to the decay state, observation was carried out with Scanning Electron Microscopy. Additional information was obtained from macerated material. The samples studied show a complex of characteristics common to the Cupressaceae family: axial tracheids without helical thickenings, presence of axial parenchyma, homogeneous rays, cupressoid cross-field pits, and absence of resin canals. The presence of dark-stained content in the ray cells and the structure of its end walls, as well as the size of the rays, allow the determination of the wood samples as Cupressus sp. and Juniperus sp. The supporting parts of the coffin construction are made from cypress, while the decorative details and an inner bed are from juniper. These results support the dating of the coffin and the known information about different usage of timbers in the production of coffins in the Bosporan Kingdom.


2020 ◽  
Vol 3 (1) ◽  
pp. 1
Author(s):  
Jorge M. S. Faria ◽  
Pedro Barbosa ◽  
Dora Martins Teixeira ◽  
Manuel Mota

The pinewood nematode (PWN), Bursaphelenchus xylophilus, induces shoot yellowing and wilting by injuring pine vascular tissues and resin canals. In Asia, it has devastated wide forests of susceptible pine with drastic ecological, economic and cultural repercussions. In 1999, it reached Europe (Portugal) and despite the actions of the authorities, it rapidly advanced to the border areas of Spain, threatening other European pine forests. Chemical control has been used in Asia with remarkable success, yet most nematicides are dangerous to human health and the environment. Natural volatile allelochemicals (VA) and derivatives are sustainable alternatives, providing many advantages to commercial nematicides. The present work summarizes available bibliographic information on VAs with activity against the PWN and reviews the chemical properties leading to nematoxicity. Published works have reported over 250 VAs in direct contact assays. Compounds highly active against the PWN belong to monoterpenoid, phenylpropanoid and aliphatic alcohols; aldehydes, ketones, carboxylic acids, esters and sulphide groups. The presence of highly electronegative elements in these structures appears to increase activity. Trisulphides, coumarins, medium carbon chain length aliphatic alcohols and derivatives comprise the top five most active allelochemicals. An indication of their mechanisms of action can be obtained from studying the reported structure–activity relationships.


2020 ◽  
Vol 53 (2) ◽  
Author(s):  
Meng Zhao ◽  
Lulu Zhao ◽  
Yunxia Wang ◽  
Shupeng Wu

2020 ◽  
Vol 27 (3) ◽  
pp. 247
Author(s):  
Danang Sudarwoko Adi ◽  
Sung-Wook Hwang ◽  
Dwi Ajias Pramasari ◽  
Yusup Amin ◽  
Hairi Cipta ◽  
...  

This study investigated the anatomical properties and absorbance characteristics of NIR spectra of four Shorea species from Indonesia. Macroscopic section revealed that Balau has similarity with Heavy Red Meranti, whereas White Meranti was almost identical with Light Red Meranti. All of the woods have diffuse porous and axial resin canals in tangential lines at the microscopic level. Original NIR spectra of Shorea species showed different absorbance characteristic. Wood density was assumed to be one of the factors that affected to the absorbances. Principal component analysis (PCA) of second derivative NIR spectra at the wavenumber 8,000-4,000 cm-1 (full) and 6,200-5,600 cm-1 (specific) showed different orientation among the Principal Component (PC) number. PC1, which contained highest spectral variation, had two closed clusters (1) Balau and Heavy Red Meranti and (2) White and Light Red Meranti at full spectral range. In contrast, the results at specific range were (1) Balau and White Meranti and (2) Heavy and Light Red Meranti. Hierarchical clustering dendrogram using PCA data from two spectral regions resulted in two types of clustering, the 8,000-4,000 cm-1 was somehow related to ‘density’, while the 6,200-5,600 cm-1 was grouped in ‘color’ information from visual inspection.  From both spectral regions, k-nearest neighbour (k-NN) classification models revealed 100% accuracy in identification four Shorea species using NIR spectra.


2020 ◽  
Vol 89 (1) ◽  
Author(s):  
Alicja Banasiak ◽  
Beata Zagórska-Marek

In conifers with spiral phyllotaxis, two numbers: one of the vascular sympodia and the second of cortical resin canals, define the shoot anatomic diameter. This in turn reflects the size and vigor of the apical meristem. Both numbers belong to the mathematical series, associated with the shoot phyllotactic pattern. The number of canals is one step lower in a series than the number of sympodia. The first one, easier to determine, automatically defines the second. Using this protocol and screening the large number of branching shoots of selected conifers, we have discovered strong correlation between orientation of vascular sympodia in the lateral and supporting branches. There was no such correlation with regard to the chiral configurations of phyllotaxis. This finding reveals the presence of special phyllotactic compensation in the case of differences in anatomic diameter of the parental and lateral shoot under the imperative of maintaining the sympodia orientation within one branching unit. Phyllotaxis of the axillary apex is evidently not established at random but adapted to the condition of the subtending axis. The monopodial, regularly branching shoot of conifers is an attractive example of biological system, which is not a sum of independent, iteratively formed units. Rather, it appears to be an entity organized on hierarchically higher level, which emerges from coordination of developmental processes in a population of the units.


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