Summer temperature in northeastern Siberia since 1642 reconstructed from tracheid dimensions and cell numbers of Larix cajanderi

2003 ◽  
Vol 33 (10) ◽  
pp. 1905-1914 ◽  
Author(s):  
Irina P Panyushkina ◽  
Malcolm K Hughes ◽  
Eugene A Vaganov ◽  
Martin AR Munro
Keyword(s):  
Cell Wall ◽  
Wall Thickness ◽  
Cell Number ◽  
Cell Wall Thickness ◽  
Cell Dimension ◽  
Cell Numbers ◽  
Age Related ◽  
Cambial Age ◽  
Northeastern Siberia ◽  
Larix Cajanderi

We reconstructed air temperature for two periods in the growth season from cell dimension and cell number variability in cross-dated tree rings of Larix cajanderi Mayr. from northeastern Siberia. Thirteen tree-ring chronologies based on cell size, cell wall thickness, and cell number were developed for AD 1642–1993. No clear evidence was found of an age-related trend in cell dimensions in the sampled materials, but cell numbers were correlated with cambial age. The chronologies contain strong temperature signals associated with the timing of xylem growth. We obtained reliable reconstructions of mean June temperature from the total cell number and July–September temperature from the cell wall thickness of latewood. June temperature and July–September temperature covaried for most of the period from AD 1642 to AD 1978. After that time, June temperature became cooler relative to July–September temperature. This difference caused disproportional changes in earlywood tracheids because of the late start of growth and cool conditions in June followed by warming during the rest of the season. The identification of this unusual recent change has shown that intraseasonal resolution may be achieved by cell dimension and cell number chronologies.

Relationships between anatomical and densitometric characteristics of black spruce and summer temperature at tree line in northern Quebec

2002 ◽  
Vol 32 (3) ◽  
pp. 477-486 ◽  
Author(s):  
Lily Wang ◽  
Serge Payette ◽  
Yves Bégin
Keyword(s):  
Cell Wall ◽  
Wall Thickness ◽  
Black Spruce ◽  
Ring Width ◽  
Cell Number ◽  
Summer Temperature ◽  
Cell Wall Thickness ◽  
Cell Diameter ◽  
Ring Cell ◽  
Densitometric Data

Tracheid cell number, cell diameter, and cell-wall thickness of black spruce (Picea mariana (Mill.) BSP) tree rings at the tree line (northern Quebec, Canada) were measured using image analysis. The densitometric data from the same samples were used to evaluate the features of image analysis. The anatomical data were correlated with summer temperature variables, including: means of pentad temperature (five consecutive days), growing season (May- September), sum of degree-days, and number of frost-free days. Our results suggest that the main cause of the pale appearance of light rings is thinner latewood cell-wall thickness. Some latewood variables are strongly correlated with corresponding indices for ring cell number and diameter, and ring cell wall thickness. Anatomical ring cell number and the sum of cell diameters (ring widths) were correlated to tree-ring width parameters derived from densitometry. Ring cell number and annual sum of cell diameter also showed very similar trends with both chronologies, suggesting that ring-width length may depend on the number of cells within a ring. Ratio diagram of double cell-wall thickness to cell radial diameter showed similar trend to wood density profile. There is a statistically significant correlation between maximum density and the highest annual ratio between cell wall thickness and lumen diameter. Cell-wall thickness was significantly correlated to maximum density, and both were significantly correlated with summer temperature variables. Our results suggest that wood anatomy may be used as a substitute to densitometry for climate reconstruction as densitometric data require expensive equipments. Also the anatomical method allows the recording of intra-annual information for dendroecological purposes.

Genetic control of wood properties in Picea glauca — an analysis of trends with cambial age

2010 ◽  
Vol 40 (4) ◽  
pp. 703-715 ◽  
Author(s):  
Patrick Lenz ◽  
Alain Cloutier ◽  
John MacKay ◽  
Jean Beaulieu
Keyword(s):  
Cell Wall ◽  
Genetic Control ◽  
Wood Density ◽  
Wall Thickness ◽  
Picea Glauca ◽  
White Spruce ◽  
Fibre Surface ◽  
Wood Properties ◽  
Cell Wall Thickness ◽  
Cambial Age

We investigated the genetic control of wood properties as a function of cambial age to enable improvement of juvenile wood attributes in white spruce ( Picea glauca (Moench) Voss). Increment cores were taken from 375 trees randomly selected from 25 open-pollinated families in a provenance–progeny trial repeated on three sites. High-resolution pith-to-bark profiles were obtained for microfibril angle (MFA), modulus of elasticity (MOE), wood density, tracheid diameter and cell wall thickness, fibre coarseness, and specific fibre surface with the SilviScan technology. Heritability estimates indicated that genetic control of cell anatomy traits and wood density increased with cambial age, whereas the genetic control of MFA and MOE remained relatively low across growth rings. Wood density, radial cell diameter, cell wall thickness, and specific fibre surface were highly heritable, indicating that significant genetic gains could be expected in tree improvement programs, although cambial age at selection may strongly influence the magnitude of realized gains. In contrast, growth-related properties, such as ring width, core length, and tree height, gave weak or nonsignificant heritability estimates. Adverse correlations between mechanical strength and properties related to paper quality suggest that breeding strategies must incorporate both types of traits to improve white spruce wood quality for different end uses.

Latitudinal variation in tree-ring and wood cell characteristics of Picea mariana across the continuous boreal forest in Quebec

2008 ◽  
Vol 38 (6) ◽  
pp. 1397-1405 ◽  
Author(s):  
Jean-Luc St-Germain ◽  
Cornelia Krause
Keyword(s):  
Cell Wall ◽  
Boreal Forest ◽  
Tree Ring ◽  
Wall Thickness ◽  
Picea Mariana ◽  
Wood Anatomy ◽  
Black Spruce ◽  
Cell Wall Thickness ◽  
Cell Numbers ◽  
Tracheid Length

Wood anatomical features measured in tree-rings are useful indicators of environmental change and wood quality. The effect of latitude on the wood anatomy of mature black spruce ( Picea mariana (Mill.) BSP) was investigated along a 500 km transect from 47°N to 52°N across the continuous boreal forest in Quebec, Canada. Total tree-ring width, earlywood width, latewood width, latewood proportion, cell numbers, tracheid length, radial diameter, lumen diameter, and cell wall thickness were measured using image analysis on samples from 15 mature stands. Our results suggest that tree-ring, earlywood, and latewood widths, cell numbers, latewood radial cell diameter, and cell wall thickness decrease with latitude. No significant trend was observed for latewood proportion, despite a slight increase with latitude (p = 0.0856). However, the high variability in radial growth seen along the gradient might explain the absence of a significant relationship. Latitude and the associated growth rate reduction had no effect on tracheid length. The existence of a latitudinal pattern of variation in black spruce wood anatomy may be the result of tree adaptation to differing environmental conditions along the gradient.

Properties of Gliricidia Wood (Gliricidia sepium) lntercropped with Cocoa (Theobroma cocoa) in Malaysia

2014 ◽  
Vol 11 (1) ◽  
pp. 51
Author(s):  
Mohd Helmy Ibrahim ◽  
Mohd Nazip Suratman ◽  
Razali Abd Kader
Keyword(s):  
Cell Wall ◽  
Specific Gravity ◽  
Moisture Content ◽  
Wall Thickness ◽  
Age Groups ◽  
Gliricidia Sepium ◽  
Cell Wall Thickness ◽  
Tree Age ◽  
Lumen Diameter ◽  
Significant Difference

Trees planted from agroforestry practices can become valuable resources in meeting the wood requirements of many nations. Gliricidia sepium is an exotic species introduced to the agricultural sector in Malaysia mainly for providing shade for cocoa and coffee plantations. This study investigates its wood physical properties (specific gravity and moisture content) and fibre morphology (length, lumen diameter and cell wall thickness) of G. sepium at three intervals according to age groups ( three, five and seven years of ages). Specific gravity (0.72) was significantly higher at seven years ofage as compared to five (0.41) and three (0.35) years age group with a mean of 0.43 (p<0.05). Mean moisture content was 58.3% with no significant difference existing between the tree age groups. Fibre diameter (22.4 mm) was significantly lower (p<0.05) for the trees which were three years of age when compared to five and seven years age groups (26.6 mm and 24. 7 mm), respectively. Means of fibre length, lumen diameter and cell wall thickness were 0.83 mm, 18.3 mm, and 6.2 mm, respectively, with no significant differences detected between trees in all age groups. Further calculation on the coefficient of suppleness and runkel ratio suggest that wood from G.sepium may have the potential for insulation board manufacturing and paper making. However, future studies should experiment the utilisation of this species for these products to determine its full potential.

Characterization of microstructures of SAN foam core using micro-computed tomography

2021 ◽  
pp. 026248932110068
Author(s):  
Youming Chen ◽  
Raj Das ◽  
Hui Wang ◽  
Mark Battley
Keyword(s):  
Cell Wall ◽  
Cell Size ◽  
Wall Thickness ◽  
Strain Localization ◽  
Cell Wall Thickness ◽  
Micro Computed Tomography ◽  
Average Cell Size ◽  
Average Cell ◽  
3D Images ◽  
Compressive Tests

In this study, the microstructure of a SAN foam was imaged using a micro-CT scanner. Through image processing and analysis, variations in density, cell wall thickness and cell size in the foam were quantitatively explored. It is found that cells in the foam are not elongated in the thickness (or rise) direction of foam sheets, but rather equiaxed. Cell walls in the foam are significantly straight. Density, cell size and cell wall thickness all vary along the thickness direction of foam sheets. The low density in the vicinity of one face of foam sheets leads to low compressive stiffness and strength, resulting in the strain localization observed in our previous compressive tests. For M80, large open cells on the top face of foam sheets are likely to buckle in compressive tests, therefore being another potential contributor to the strain localization as well. The average cell wall thickness measured from 2D slice images is around 1.4 times that measured from 3D images, and the average cell size measured from 2D slice images is about 13.8% smaller than that measured from 3D images. The dispersions of cell wall thickness measured from 2D slice images are 1.16–1.20 times those measured from 3D images. The dispersions of cell size measured from 2D slice images are 1.12–1.36 times those measured from 3D images.

Variation in xylem anatomy of selected populations of lodgepole pine

2001 ◽  
Vol 31 (11) ◽  
pp. 2049-2057 ◽  
Author(s):  
Tongli Wang ◽  
Sally N Aitken
Keyword(s):  
Cell Wall ◽  
Wall Thickness ◽  
Slow Growth ◽  
Lodgepole Pine ◽  
High Density ◽  
Cell Wall Thickness ◽  
Fast Growth ◽  
Low Density ◽  
Xylem Anatomy ◽  
Latewood Density

Variation in xylem anatomy among selected populations of lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) was examined using digital image analysis based on an annual growth ring (age 10) per tree. Four subpopulations were selected using the following criteria for height growth and wood density: (i) fast growth and high density; (ii) slow growth and high density; (iii) fast growth and low density; and (iv) slow growth and low density. Significant differences were found among subpopulations for several anatomical parameters including tracheid density, lumen size, and cell wall thickness that may affect the economic value and utilization of wood. Principal component analysis indicate that the first four principal components (PCs) were associated with (i) ring area (PC1), (ii) earlywood density (PC2), (iii) latewood density (PC3), and (iv) lumen shape in earlywood (PC4), suggesting that these aspects of wood properties and growth are controlled by different sets of genes. Relative contributions of total number of tracheids, tracheid lumen size, and cell wall thickness to ring area and correlations between cell wall area proportion and X-ray density are discussed.

scholarly journals Host Barriers and Responses to Uncinula necator in Developing Grape Berries

2004 ◽  
Vol 94 (5) ◽  
pp. 438-445 ◽  
Author(s):  
Andrea Ficke ◽  
David M. Gadoury ◽  
Robert C. Seem ◽  
Dale Godfrey ◽  
Ian B. Dry
Keyword(s):  
Cell Wall ◽  
Powdery Mildew ◽  
Wall Thickness ◽  
Infection Process ◽  
Cell Wall Thickness ◽  
Antifungal Compound ◽  
Uncinula Necator ◽  
Grape Berries ◽  
Pathogenesis Related ◽  
Cuticle Thickness

Grape berries are highly susceptible to powdery mildew 1 week after bloom but acquire ontogenic resistance 2 to 3 weeks later. We recently demonstrated that germinating conidia of the grape powdery mildew pathogen (Uncinula necator) cease development before penetration of the cuticle on older resistant berries. The mechanism that halts U. necator at that particular stage was not known. Several previous studies investigated potential host barriers or cell responses to powdery mildew in berries and leaves, but none included observation of the direct effect of these factors on pathogen development. We found that cuticle thickness increased with berry age, but that ingress by the pathogen halted before formation of a visible penetration pore. Cell wall thickness remained unchanged over the first 4 weeks after bloom, the time during which berries progressed from highly susceptible to nearly immune. Autofluorescent polyphenolic compounds accumulated at a higher frequency beneath appressoria on highly susceptible berries than on highly resistant berries; and oxidation of the above phenolics, indicated by cell discoloration, developed at a significantly higher frequency on susceptible berries. Beneath the first-formed appressoria of all germinated conidia, papillae occurred at a significantly higher frequency on 2- to 5-day-old berries than on 30- to 31-day-old fruit. The relatively few papillae observed on older berries were, in most cases (82.8 to 97.3%), found beneath appressoria of conidia that had failed to produce secondary hyphae. This contrasted with the more abundantly produced papillae on younger berries, where only 35.4 to 41.0% were located beneath appressoria of conidia that had failed to produce secondary hyphae. A pathogenesis-related gene (VvPR-1) was much more highly induced in susceptible berries than in resistant berries after inoculation with U. necator. In contrast, a germin-like protein (VvGLP3) was expressed within 16 h of inoculation in resistant, but not in susceptible berries. Our results suggest that several putative barriers to infection, i.e., cuticle and cell wall thickness, antimicrobial phenolics, and two previously described pathogenesis-related proteins, are not principal causes in halting pathogen ingress on ontogenically resistant berries, but rather that infection is halted by one or more of the following: (i) a preformed physical or biochemical barrier near the cuticle surface, or (ii) the rapid synthesis of an antifungal compound in older berries during the first few hours of the infection process.

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