Development of near infrared reflectance analysis calibrations for estimating genetic parameters for cellulose content in Eucalyptus globulus

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 (8) ◽  
pp. 1577-1586 ◽  
Author(s):  
Geoffrey M. Downes ◽  
Christopher E. Harwood ◽  
John Wiedemann ◽  
Nick Ebdon ◽  
Helen Bond ◽  
...  

There is little published information on the variability of pulp yield within eucalypt stems. This is primarily due to the difficulty in measuring pulp yield in small samples, especially those obtained nondestructively. Thus, information of the effect of site, climate, and silviculture on pulp yield variability is lacking, minimizing its consideration in the economic optimization of pulpwood production. Near infrared spectroscopic measurement of pulp yield directly from intact wood surfaces at a small, radial sampling interval provides forest managers with opportunities to better understand and manage its sources of variability. Calibrations based on solid wood samples were constructed to describe radial variation in Kraft pulp yield and cellulose content using intact wood samples from Eucalyptus globulus Labill. Plantations at three sites with contrasting annual rainfall were studied. Pulp yield and cellulose content were higher at the more productive, wetter sites. Outer wood near the cambium had pulp yield values up to 8% higher than those at the pith. There was no clear intra-annual cycle of variation. The more productive sites exhibited significantly steeper pith-to-bark increases in pulp yield than the driest site. This has implications for optimizing pulp productivity by considering rotation length and site quality.


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.


1994 ◽  
Vol 6 (10) ◽  
pp. 889-894 ◽  
Author(s):  
Jürgen Stein ◽  
Bernd Purschian ◽  
Ursula Bieniek ◽  
Wolfgang F. Caspary ◽  
Bernhard Lembcke

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