scholarly journals Genetic Variation of Physical and Chemical Wood Properties of Eucalyptus globulus

2005 ◽  
Vol 54 (1-6) ◽  
pp. 160-166 ◽  
Author(s):  
L. A. Apiolaza ◽  
C. A. Raymond ◽  
B. J. Yeo

Abstract This study considered the degree of genetic variation for diameter (DBH), basic density (BD), predicted pulp yield (PPY), fibre length (FL), microfibril angle (MFA) and cellulose content (CC) amongst eight subraces of Eucalyptus globulus growing in a field trial in NW Tasmania. There were significant subrace effects for BD, FL and CC. This variation affected the relative profitability of the subraces for pulp production. On average, the most profitable subraces (on NPV/ha over the base population mean) were Strzelecki Ranges ($862.04), Western Otways ($657.80) and Strzelecki Foothills ($576.81). The genetic control (heritability) of variation in DBH, FL and MFA was moderate (0.15 < h2< 0.27), while control for BD, PPY and CC was high (h2> 0.40). Genetic correlations between growth and wood properties were not statistically significant, except for DBHMFA (-0.86). Most genetic correlations amongst wood properties were outside the parametric space (< -1 or >1), but there were significant correlations between BDMFA (-0.70) and PPY-CC (0.82). The empirical response to selection on an index based on a pulp wood objective (which included volume and basic density) resulted in a gain of 4.3% for DBH, 7.9% for BD and marginal changes for all other traits, with a net impact in profit of $1,270/ha. However, future profit calculations will need to consider the effect of FL, MFA and CC on the economics of wood processing to fully evaluate the economic impact of breeding.

2000 ◽  
Vol 30 (1) ◽  
pp. 136-144 ◽  
Author(s):  
C A Raymond ◽  
A Muneri

The effects of N and P fertilizers applied to Eucalyptus globulus Labill. at plantation establishment on basic density, fibre length, fibre coarseness, predicted pulp yield, and N and P concentration in the wood were examined by sampling four fertilizer factorial trials: three in Victoria and one in Western Australia. Treatments sampled were control, maximum levels of N and P by themselves and combined. Growth responses varied across sites with significant growth responses at the Victorian sites but no response at the Western Australian site. An interaction was suggested between rainfall and the effects of the fertilizer; wood properties at the drier sites were detrimentally affected by fertilizer but there was little effect at the wetter sites. On the two drier sites, application of both N and P, alone or in combination, resulted in changes in density, shorter fibres, and slightly lower predicted pulp yield. Addition of both N and P increased the levels of these nutrients in the wood at the three Victorian sites. Changes occurred in wood properties in the absence of growth responses to the applied fertilizer indicating that these changes were not induced by changing tree growth rate.


Holzforschung ◽  
2002 ◽  
Vol 56 (3) ◽  
pp. 244-252 ◽  
Author(s):  
R. Wimmer ◽  
G.M. Downes ◽  
R. Evans ◽  
G. Rasmussen ◽  
J. French

Summary Fibre length, microfibril angle and wood density were measured in eight-year-old Eucalyptus globulus clones planted on three different sites. Samples were chipped and pulped, and the pulps beaten prior to preparation of 60g/m2 handsheets. Eleven physical handsheet properties, together with pulp freeness, were measured using standard methods. Direct relationships between wood properties and pulp/paper properties were studied using path analysis. Fibre length had a strong, direct effect on tear index, bending stiffness, freeness, pulp yield and active alkali consumption. Wood density was a strong predictor of most handsheet properties: high density woods produced bulkier, more porous sheets with higher bending stiffness, while lower density woods produced smoother, denser sheets with higher tensile strength.The effect of microfibril angle was small and more evident in handsheets made from beaten pulp.


2002 ◽  
Vol 32 (1) ◽  
pp. 170-176 ◽  
Author(s):  
C A Raymond ◽  
L R Schimleck

Determining kraft pulp yield in the traditional way is slow and expensive, limiting the numbers of samples that may be processed. An alternative is to use a secondary standard, such as cellulose content of the wood, which is strongly correlated with kraft pulp yield. The feasibility and efficiency of predicting cellulose content using near infrared reflectance (NIR) analysis was examined for Eucalyptus globulus Labill. Calibrations for NIR prediction of cellulose content indicated that NIR analysis could be used as a reliable predictor. Standard errors of calibration were 1% or lower, and there was excellent agreement between laboratory and predicted cellulose values. Cellulose content was under moderate genetic control (h2 ranging from 0.32 to 0.57), and genetic correlations with tree diameter and basic density were variable (ranging from –0.11 to –0.51 and –0.33 to 0.67, respectively). The advantages, disadvantages, and potential applications of NIR analysis for predicting cellulose content are examined.


2010 ◽  
Vol 40 (5) ◽  
pp. 917-927 ◽  
Author(s):  
Desmond J. Stackpole ◽  
René E. Vaillancourt ◽  
Geoffrey M. Downes ◽  
Christopher E. Harwood ◽  
Brad M. Potts

Pulp yield is an important breeding objective for Eucalyptus globulus Labill., but evaluation of its genetic control and genetic correlations with other traits has been limited by its high assessment cost. We used near infrared spectroscopy to study genetic variation in pulp yield and other traits in a 16-year-old E. globulus trial. Pulp yield was predicted for 2165 trees from 467 open-pollinated families from 17 geographic subraces. Significant differences between subraces and between families within subraces were detected for all traits. The high pulp yield of southern Tasmanian subraces suggested that their economic worth was previously underestimated. The narrow-sense heritability of pulp yield was medium (0.40). The significant positive genetic correlation between pulp yield and diameter (0.52) was at odds with the generally neutral values reported. The average of the reported genetic correlations between pulp yield and basic density (0.50) was also at odds with our nonsignificant estimate. Pulp yield of the subraces increased with increasing latitude, producing a negative correlation with density (–0.58). The absence of genetic correlations within subraces between pulp yield and density suggests that the correlation may be an independent response of the two traits to the same or different selection gradients that vary with latitude.


2012 ◽  
Vol 42 (9) ◽  
pp. 1724-1732 ◽  
Author(s):  
David Blackburn ◽  
Ross Farrell ◽  
Matthew Hamilton ◽  
Peter Volker ◽  
Chris Harwood ◽  
...  

Genetic improvement of wood properties affecting the quality of pulpwood and peeled veneer products is of general interest to tree breeders worldwide. If the wood properties of Eucalyptus nitens (H. Deane & Maiden) Maiden are under genetic control and the correlations between them are favourable, it may be possible to breed to simultaneously improve the plantation resource for both products. Acoustic wave velocity (AWV) measured in standing trees can predict wood stiffness, basic density, and kraft pulp yield (KPY) and therefore has the potential for use in tree breeding programs. From an E. nitens progeny trial in Tasmania, 540 trees were selected for rotary peeling. Of the wood properties assessed, there were significant differences among races in diameter, stem straightness, standing-tree, log, and billet AWV, and near infrared predicted cellulose content (CC). All traits displayed significant within-race genetic variation, and genetic correlations between AWV and veneer sheet modulus of elasticity (MOE) and between AWV and KPY and CC were strongly positive and highly significant. A similar relationship was found between veneer sheet MOE and KPY and between diameter at breast height and veneer sheet MOE. Basic density was genetically correlated with AWV and veneer sheet MOE. Results indicate that it should be possible for breeders to simultaneously improve properties in pulpwood and peeled veneer products and that AWV measured in the standing tree shows promise as a breeding selection criterion for both pulpwood and peeled veneer products.


2009 ◽  
Vol 58 (1-6) ◽  
pp. 252-261 ◽  
Author(s):  
Matthew G. Hamilton ◽  
C. E. Harwood ◽  
B. M. Potts

Abstract Genetic variation in wood-sample gross shrinkage and basic density was examined in a Eucalyptus globulus base population trial growing in Tasmania, Australia. Gross shrinkage, which includes all components of shrinkage including collapse, was assessed in four ways (calliper- and visually-assessed tangential shrinkage, volumetric shrinkage and radial shrinkage) on samples dried at three temperatures (22°C, 60°C and 105°C). Significant differences between subraces were observed using all measures of gross shrinkage for two or more of the three drying treatments. Furthermore, significant additive genetic variation within subraces was observed in calliper- and visually-assessed gross shrinkage under two or more of the drying treatments, with narrowsense heritabilities greater than or equal to 0.35. There was no obvious trend in heritabilities or coefficients of additive genetic variation with drying temperature. Under the 105°C drying treatment, subrace correlations among calliper-, visually- and volume-assessed gross shrinkage were positive and very strong (≥ 0.97), while these measures were less strongly correlated with radial gross shrinkage at the subrace level (≤ 0.77). Withinsubrace genetic correlations among the first three measures were also strongly positive (≥ 0.95). These high genetic correlations suggest that different drying regimes and the calliper, visual and volume methods of assessment could be used interchangeably to select for reduced tangential gross shrinkage. Estimated subrace and genetic correlations between basic density and measures of gross shrinkage were universally negative (i.e. favourable), although not all were significantly different to zero.


2006 ◽  
Vol 55 (1-6) ◽  
pp. 217-228 ◽  
Author(s):  
Sotelo Montes ◽  
R. E. Hernández ◽  
J. Beaulieu ◽  
J. C. Weber

Abstract Calycophyllum spruceanum (Benth.) Hook. f. ex K. Shum. is an important timber-tree species in the Peruvian Amazon Basin. As farmers and industry often use wood from young trees, it is important to investigate variation in juvenile wood properties in this species. A provenance/progeny test was established to evaluate genetic variation in growth and wood properties of young trees, the strength of their genetic control as well as their interrelationships both at the genetic and the phenotypic level in different planting zones. In this paper, results are presented for tree height and stem diameter (near ground level) at 16, 28 and 39 months; and stem diameter and basic density of the wood at breast height at 39 months. Significant variation due to provenances and especially due to families within provenances was found in growth and wood density. Phenotypic and genetic correlations indicated that larger trees tended to have denser wood. Wood density had higher heritability than height and diameter; and genetic control over height, diameter and density was generally highest in the planting zone where trees grew most rapidly.


Holzforschung ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Manuel F. Rocha-Sepúlveda ◽  
Dean Williams ◽  
Mario Vega ◽  
Peter A. Harrison ◽  
René E. Vaillancourt ◽  
...  

Abstract Microfibril angle (MFA) is a key biological trait contributing to wood stiffness, which is a common breeding objective for solid wood products in many tree species. To explore its genetic architecture, area-weighted MFA was measured in two Eucalyptus nitens progeny trials in Tasmania, Australia, with common open-pollinated families. Radial strips were extracted from 823 trees in 131 families and MFA assessed using SilviScan-2®. Heritability, genotype-by-environment interaction and inter-trait genetic correlations were evaluated to examine the genetic variability and stability of MFA and its relationships with other solid wood and pulpwood selection traits. Significant family variation was found for MFA in both trials. There was no significant genotype-by-environment interaction and the across-site narrow-sense heritability was 0.27. MFA was genetically independent of basic density, growth, and tree form. However, MFA was strongly and favourable genetically correlated to acoustic wave velocity in standing trees, modulus of elasticity and kraft pulp yield (KPY). The present study has shown that genetic improvement of E. nitens for pulpwood selection traits is unlikely to have adversely affected MFA, and thus timber stiffness. Rather these results suggest the possibility that selection for increased KPY may have indirectly improved MFA favourably for solid wood products.


IAWA Journal ◽  
2006 ◽  
Vol 27 (3) ◽  
pp. 243-254 ◽  
Author(s):  
Teresa Quilhó ◽  
Isabel Miranda ◽  
Helena Pereira

Within-tree variations in fibre length, width, wall thickness and wood basic density of Eucalyptus grandis × E. urophylla (urograndis) were studied in five 6.8-yr-old seedling trees and five 5.6-yr-old trees from one clone from Brazil. Samples were taken at 5%, 25%, 35%, 55%, 65% and 90% of stem height and five radial positions (10%, 30%, 50%, 70% and 90% of radius). The tree average fibre length, width and wall thickness were in seed and clone trees: 0.955 mm and 1.064 mm, 18 μm and 20 μm, 3.6 μm and 4.4 μm respectively. The axial variation of fibre dimensions was very low, while there was a consistent but small increasing trend from pith to periphery. The basic density ranged from 397–464 kg/m3 to 486–495 kg/m3 respectively in seedling and clone trees with a low variation along the stem. In comparison with other eucalypt pulpwood, e.g. E. globulus, the urograndis hybrid showed similar fibre dimensions and lower basic density. Overall the within-tree variation of these wood properties was low and age had a small impact on the variation of density and fibre dimensions.


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