NZJFS - Volume 38 (2008)
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Regional log market integration in New Zealand
Niquidet, K. ; Manley, B.
In this paper the integration of log prices across four regions in New Zealand was assessed. A series of monthly prices from January 1995 to December 2006 for five radiata pine (Pinus radiata D. Don) log grades in each of the regions were tested for co-integration using Johansen’s method and Engle-Granger pair wise tests. Prices for export grades displayed significant integration across regions and generally followed the law of one price. However, markets for domestic grades tended to be regionally segregated. These results are most likely due to the high costs of transporting logs between regions. Future modelling will need to incorporate such transportation costs in order to adequately characterise log markets in the country. -
Factors influencing the formation of resin pockets in pruned radiata pine butt logs from New Zealand
Woollons, R. ; Manley, B. ; Park, J.
Resin pocket incidence is an important variable when assessing the potential appearance-grade quality of wood from Pinus radiata D.Don in New Zealand. High levels diminish value. Several theories have been proposed to explain the origin of resin pockets; in New Zealand researchers have considered silviculture to be an important factor. A comprehensive database derived from stand sampling and sawing studies has been used to explore the relationship between butt log resin pocket incidence and twenty nine climatic, physical, soil and silvicultural variables. A total of 1055 sites, distributed over 281 stands in four distinct regions, were analysed. The incidence of butt log resin pockets ranged from 0 to 7.65 RP/m2 . Multiple linear regression methods were utilised to build a prediction model. Initially, four significant predictors were isolated, vapour pressure deficit, solar radiation, a measure of wind damage and readily available water. Further analysis showed a fifth variable (tree diameter breast height/size of the defect core), also contributed to the model. The R2 value of the equation was 0.50 and residual analysis showed the model to be generally unbiased over four locations. Average daily October vapour pressure deficit made the biggest (58 %) contribution to the regression and the coefficients were all positive except water availability which was negative, as expected. We interpreted these results to infer that stress (associated with moisture and exposure related issues) in conjunction with other factors, including accelerated growth, is a major cause of resin pocket incidence. -
Effect of non-tariff barriers on secondary processed wood product trade: New Zealand exports to the United States, China and Japan
Turner, J. A. ; Buongiorno, J. ; Zhu, S. ; Maplesden, F.
Secondary processed wood products – builder’s carpentry and joinery, mouldings and millwork, wooden furniture, and prefabricated buildings – have grown significantly in importance in the global trade of wood products. At the same time there has been increased use of non-tariff barriers to restrict their trade. These barriers could have an important impact on the trade of secondary processed products, as well as the production, consumption and trade of wood products used in their manufacture. This paper describes the development of an economic model of the international trade of secondary processed wood products within the structure of the spatial equilibrium Global Forest Products Model. The model was used to assess the effect of removing non-tariff barriers to New Zealand exports of prefabricated housing, and builder’s carpentry and joinery to three key trading partners, the United States, China and Japan. New Zealand exporters would benefit the most from removal of non-tariff barriers that account for the greatest proportion of production costs, i.e., higher design values and engineering certificates for prefabricated houses exported to Japan. The calculated increase in trade value from improved market access is, however, a modest 0 to 9.2% of New Zealand’s total wood products trade by 2030. -
Performance of resistance-based moisture meters as a function of timber preservative treatment
Kear, G. ; Kell, N. J.
Three commercial resistance-based moisture meters have been used to measure the moisture content of ten classes of solid timber product specified for use in Australasia. All of the timbers were based on Pinus radiata D.Don (Radiata Pine). With the exception of a single untreated classification, the timber specimens were treated with waterborne or light organic solvent-based commercial preservatives. Moisture content data was measured and is presented as a function of relative humidity at 21±2°C. Verification of timber moisture content was provided by the standard oven-dry method specified by Australian Standards/Standards New Zealand 1080.1. The results presented in this report indicate that standardisation of meter design and electrode geometry beyond that already specified within publications such as Australian Standards/Standards New Zealand 1080.1 may be required. When the individual moisture meter correction values (as supplied with each meter type) were applied to the directly measured timber resistance derived data, all of the meters were able to accurately determine the moisture content of untreated Pinus radiata to within ±1 moisture meter units (% wt./wt.). In many instances, however, the introduction of preservative treatments significantly lowered the accuracy of the meters to a degree which was dependent on the timber preservative type and the mode of meter operation. Of particular concern was the inability of some meters to accurately determine the moisture content of typical framing timbers containing light organic solvent preservatives or certain waterborne preservatives (equilibrated at 65% and 75% relative humidity) within at least ±2 moisture meter percentage units. -
Effectiveness of routine forest health surveillance in detecting pest and disease damage in eucalypt plantations
Wardlaw, T. ; Bashford, R. ; Wotherspoon, K. ; Wylie, R. ; Elliot, H.
Routine health surveillance of forestry plantations in Australia typically involves inspections from the air, roadside and ground to detect, identify and map health problems caused by pests and diseases. An often-cited objective of routine health surveillance is the early detection of new incursions of exotic pests and diseases. To be effective, this requires the incursion be detected when damage is often cryptic either because of low incidence or low severity. However, the reliability of routine surveillance in detecting damage when symptoms are still cryptic has not been tested. We measured the efficiency of aerial, roadside and ground inspections to detect nine different types of damage symptom ranging from very obvious (mortality and dead tops) to very cryptic (stem cankers and stem borers), each occurring at a range of incidences among five 3-year-old Eucalyptus globules Labill. plantations. Cryptic damage symptoms (stem borers, stem cankers and kino exudation) could not be reliably detected using any of the inspection platforms even when their incidence, within small patches, was as high as 2%. Conversely, dead tops were detected most efficiently by aerial inspection, at incidences as low as 0.1%. The crown symptoms produced by moderately severe insect defoliation or necrotic leaf lesions due to Mycosphaerella infection could be detected with equal efficiency from roadside and ground inspections but could not be reliably detected from aerial inspection. We conclude that the combination of aerial and roadside inspection provide sufficient resolution to detect operationally relevant damage, i.e. damage of sufficient severity to consider remedial treatment. The inclusion of ground surveys does little to enhance the capacity of routine health surveillance to detect the more cryptic damage symptoms that characterise the early stages of outbreaks by stem and branch-attacking pests and pathogens. Routine ground surveillance of plantations is unlikely to detect damage by new incursions at a sufficiently early stage when eradication may be feasible. -
Effects of bark removal on acoustic velocity of Douglas-fir logs
Murphy, G. E. ; Amishev, D.
The acoustic velocities of 81 Douglas-fir logs were measured before and after debarking in a logyard. Bark removal led to an average increase in acoustic velocity of 3.6%. A regression model for determining the effect of bark removal on the change in acoustic velocity was developed. This model predicted an increase in acoustic velocity of 4.6% if 100% of bark was removed. This is similar to increases in velocity found by other researchers for radiata pine logs. -
Eucalyptus longirostrata: A potential species for Australia's tougher sites?
Henson, M. ; Smith, H. J. ; Boyton, S.
In 2004 and 2005, Forests NSW established six progeny trials of Eucalyptus longirostrata (Blakely) L.A.S.Johnson & K.D.Hill (grey gum), in the Hunter Valley and northern New South Wales, Australia, with a total of 79 families in the two trial series. A third series of trials, with 74 families, was planted on four sites during 2007. The three trial series eventually contained a total of 121 families from eight provenances. The 2004 series of trials located near Casino and Grafton (northern NSW) and Singleton (Hunter Valley) were assessed at age 31 months for growth and stem straightness. Survival was high on all three sites, ranging from 89% (Grafton) to 95% (Singleton). Height growth was greatest at Grafton (trial mean 8.6 m) with the poorest growth recorded at Singleton (trial mean 2.4 m) reflecting the severe drought conditions at this site. Height was under moderate to high genetic control with individual-tree, narrow-sense heritabilities (h?2) for height at 31 months estimated to be 0.34, 0.49, and 0.33 at the Casino, Grafton, and Singleton trials, respectively, assuming a coefficient of relationship within open-pollinated families of 0.25. The across-site correlations for all traits measured were high, suggesting that at age 31 months there was little genetic x environment interaction across the range of site types represented by the three trial series -
Prospects for genetic improvement of Eucalyptus cladocalyx in Western Australia
Callister, A. ; Bush, D. ; Collins, S. ; Davis, W.
Sugar gum (Eucalyptus cladocalyx F. Muell.) plantations can produce high-value timber over a medium-length rotation in the 400- to 600-mm rainfall zone of southern Australia. We evaluated growth and tree form in sugar gum family trials on three sites in Western Australia. The trials contained 42 open-pollinated families originating from wild collections in the southern Flinders Ranges and Kangaroo Island (wild families) and four planted stands. Height and stem diameter were assessed at 3.5 and 5.5 years and stem volume was calculated. Branch size and stem straightness were scored at 3.5 years and axis persistence was assessed at 5.5 years. Mixed model equations were fitted to estimate heritability (h?2) for all traits, genetic correlations between traits (Type A), and between sites (Type B), and age-age correlations for growth parameters. Progeny from planted stands outperformed those from the wild for stem volume and straightness. Those of Kangaroo Island displayed the largest branches and poorest axis persistence. Estimates of narrow-sense within provenance heritability for stem volume at the three sites ranged from 0.40 to 0.47 and were similar at 3.5 and 5.5 years. The mean h? 2 estimate was 0.11 for branch size, 0.29 for stem straightness, and 0.21 for axis persistence. Genetic correlations for growth traits between ages 3.5 and 5.5 were extremely high, the weakest being 0.96. Genetic correlations between growth and form traits were generally positive (i.e., favourable) but not statistically significant. Genetic correlations between sites for growth and stem straightness were not significantly different from unity. Our results suggest that selection and breeding of superior individuals from high-ranking families could yield significant gains in growth and modest gains in stem straightness. A single breeding population may suit a wide range of sites in Western Australia given the lack of genotype x site interaction -
Genetic variation on shrinkage properties of Eucalyptus pilularis assessed using increment cores and test blocks
Pelletier, M. C. ; Henson, M. ; Boyton, S. ; Thomas, D. ; Vanclay, J.
Assessments of genetic variation in wood properties are difficult and expensive to carry out. As a consequence, the inclusion of wood quality traits in eucalypt breeding programmes has to date been limited. This study was part of a large investigation into the use of non-destructive methods of assessing wood properties by comparing the results with those from traditional destructive methods. This component of the study investigated the genetic variation in linear shrinkage of 152 open-pollinated families of Eucalyptus pilularis (Smith) at 17% m.c., 12% m.c., and 5% m.c. Increment cores and test blocks were used to assess radial and tangential shrinkage as well as their ratio. Heritability estimates were moderate for tangential shrinkage but not significant for radial shrinkage or the ratios of the two. The genetic correlation between shrinkage measured on cores and on blocks at this stage was not sufficient to justify the use of increment cores alone in genetic assessments. Basic density had a moderate and negative correlation with tangential shrinkage, suggesting that selecting for higher basic density may help reduce tangential shrinkage. The increment core method was not successful at measuring radial shrinkage due to core distortion. Measurements from scans and blocks showed that radial shrinkage was not heritable -
Genetic variation in wood basic density and knot index, and their relationship with growth traits for Acacia auriculiformis in northern Vietnam
Hai, P. H. ; Jansson, G. ; Harwood, C. ; Hannrup, B. ; Thinh, H. H. ; Pinyopusarerk, K.
One hundred and forty families from 13 provenances of Acacia auriculiformis A. Cunn. ex Benth. were tested in a progeny trial on a typical hill site in northern Vietnam. Two selective thinnings were done to retain the single best tree, in terms of vigour and straightness, in each four-tree family plot. All remaining trees were measured to obtain estimates of individual-tree narrow-sense heritabilities (h? 2) and additive genetic correlations (r? A) for growth traits (height, diameter, tree volume), stem quality traits (bark thickness, straightness, forking, and knot index), pilodyn penetration, and wood basic density. The h? 2 for growth traits and straightness increased over time from age 3 to ages 5 and 9. Similarly, h?2 for density also increased from corewood to outerwood. For growth traits at age 9, h?2 ranged from 0.36 to 0.39. The observed heritabilities of density and pilodyn penetration h?2 = 0.61 and 0.47, respectively) were consistently higher than for growth traits. However, the values for stem quality traits (h?2 0.12 to 0.31) were lower than for growth traits, with the exception of BRK (0.39). Estimated coefficients of additive genetic variation (CVA) were high for growth traits at all ages (4.5 % to 26.2%) and were very high for stem quality traits (14.7 to 26.2%) at age 9. The value of CVA for density was around 8% at different ages. Age-age correlations for all growth traits, straightness, and density were high. The r?A between growth traits and density were not significantly different from zero. The r? A between growth traits and stem quality traits, except straightness, were low to moderate (r?A -0.45 to 0.65), while strong positive genetic correlations (r?A 0.79 to 0.96) were found between growth traits and straightness. Strong negative genetic correlation between pilodyn penetration and density r? A = -0.88) indicated that pilodyn would reliably rank trees for basic density -
Genetic variation in wood basic density and pilodyn penetration and their relationships with growth, stem straightness, and branch size for Eucalyptus urophylla in northern Vietnam
Kien, N. D. ; Jansson, G. ; Harwood, C. ; Almqvist, C. ; Thinh, H. H.
Genetic parameters r wood basic density and pilodyn penetration and their relationships with diameter, height, stem straightness, and branch size were estimated in two thinned open-pollinated progeny trials of Eucalyptus urophylla S. T. Blake in northern Vietnam at the ages of 8 and 9 years. There were 127 families in one trial and 144 in the other trial; all families were from nine natural provenances, and 120 of them were common to both sites. At the time of assessment, each family was represented by four to eight trees in each trial. Wood basic density, estimated from 5-mm increment cores taken at breast height, averaged 0.51 g/cm3 across the two trials. Estimated narrow-sense individual tree heritability (h?2) for wood basic density was 0.60, and that for pilodyn penetration it was 0.42. The estimated coefficient of additive genetic variation (CVA) for wood basic density was 6.3%. There were no significant differences between provenances for these two traits. The estimated genetic correlation between pilodyn penetration and wood density was -0.86, indicating that pilodyn could be used reliably as an indirect measurement of wood basic density. The estimated genetic correlations among wood basic density and diameter at breast height, height, stem straightness, and branch size at each site were weak. The strong estimated genetic correlation between inner wood density and total core density indicated that reliable selection for wood density could be carried out at age 3 years. Estimated genetic correlations between sites for both wood basic density and pilodyn penetration were strong, indicating little genotype-by-environment interaction for these traits across these two similar environments -
Multi-environment trial analysis for Pinus radiata
Ding, M. ; Tier, B. ; Dutkowski, G. W. ; Wu, H. X. ; Powell, M. B. ; McRae, T. A.
A stem-diameter data set of five combined trials of Pinus radiata D. Don was used to identify and determine the nature of genetics by environment (GxE) interaction. The restricted maximum likelihood approach was applied to handle the main issues of the multi-environment trial analysis: (1) Testing sources of heterogeneity of variance and lack of between-sites genetic correlation; (2) Modelling the heterogeneity of error variance among trials and micro-environmental variation within each trial; and (3) Selecting the best model for prediction of breeding values. Model comparison was based on the criterion of log-likelihood. The significance of variance components was tested by the likelihood ratio test which showed that all sources of GxE interactions were highly significant, indicating that GxE interactions occurred in these five trials due to both the heterogeneity of variances and the lack of correlation. Estimates of Type B genetic correlations were increased slightly by correcting for the heterogeneity of variances. The full model, which accommodated heterogeneity of error variances between trials, spatial variation within trials, and fitting a separate GxE interaction variance for each trial, was superior to other models for this multi-environment trial -
Application of GGE biplot analysis to evaluate genotype (G), environment (E) and GxE interaction on Pinus radiata: A case study
Ding, M. ; Tier, B. ; Yan, W. ; Wu, H. X. ; Powell, M. B. ; McRae, T. A.
Genetics, genetics xenvironment(GGE) biplot analysis is an effective method, based on principal component analysis, to fully explore multi-environment trial data. It allows visual examination of the relationships among the test environments, genotypes, andthegenotype x environment (GxE) interactions. Data from multi-environment trials of P. radiata D. Don containing 165 to 216 families in five environments were used to demonstrate the results and application of GGE biplot analysis. There were non-overlapping clusters of two and three sites, which indicated two distinct environments. The best family for both of the distinct environments was also identified. Genetic correlations among sites ranged from 0.98 to -0.50, indicating that there were large GxE interactions among the test environments -
Selecting hybrid pine clones for deployment - The pointy end of wood quality improvement
Harding, K. J. ; Copley, T. R. ; Peters, R. F. ; Dieters, M. J. ; Nester, M. R. ; Keys, M. G. ; Toon, P. G. ;
A clonal forestry research programme on Pinus elliottii Engelm. (slash pine) x P. caribaea Morelet var. hondurensis Barrett & Golfari (Caribbean pine) hybrids commenced in Queensland in 1986. Each cycle of clonal tests covered about 5 calendar years from field planting, and studies of wood quality variation have so far been used in selecting superior clones from the first three series of tests for commercial plantation deployment. Experience from the Series III clonal selection round is used to highlight the difficulties of ranking elite clones given a large number of growth, form, and wood property traits. Three to six ramets were felled from the best 32 clones in the Series III trials at age 6.8 years and a 3-m butt log from each was sawn into 70 ž 35-mm structural boards. The clones sawn were ranked for routine deployment using data on growth, form, and wood traits. All recovered boards were assessed for distortion and tested for modulus of elasticity and modulus of rupture. Various non-destructive wood evaluation methods were used to estimate modulus of elasticity (wood stiffness) in these trees. Standing tree acoustic velocity assessed with an ST300 tool was slightly less strongly correlated phenotypically with the average modulus of elasticity of the recovered boards (r = 0.88**) than with predictions of modulus of elasticity from resonance vibration test samples and SilviScan estimates (both r = 0.89**). Moderate phenotypic relationships were found for individual tree means between average twist of the sawn boards and the average spiral grain angle of growth rings 2, 3, and 4 (r = 0.70**) assessed using a breast-height 12-mm increment core, and between average bow in the boards and average microfibril angle (r = 0.64**) from SilviScan assessments of core samples -
Eucalyptus nitens genetic parameters.
Hamilton, M. G. ; Potts, B. M.
Eucalyptus nitens (Deane et Maiden) Maiden is a significant plantation species in temperate regions of the world, with breeding occurring in Australia, Chile, South Africa, and New Zealand. We reviewed published genetic parameters from over 100 field trials and calculated average values for key growth, wood property, tree architecture, and fitness traits. Parameter estimates from control-pollinated progeny trials were rare. However, numerous parameter estimates were available from open-pollinated progeny trials for several traits, such as diameter and wood basic density, suggesting that for this mating type our average parameter estimates are likely to be robust. In open-pollinated trials, average heritabilities for growth traits (e.g., h?2op = 0.26 for diameter) were generally lower than those for wood property traits (e.g., h?2op = 0.51 for basic density). However, this trend was reversed in average additive genetic coefficients of variation (e.g., CVa=13.3% for diameter and 4.5% for basic density). Inter- age genetic correlations for stem diameter ranged from 0. 68 to 1.00 but were not available for important wood property traits (e.g., cellulose content and pulp yield). For most traits, inter-site genetic correlations were, on average, positive and strong (e.g., r?g =0.70 for diameter) but some weak individual estimates were observed. The average genetic correlation between diameter and basic density was -0.27. Few estimates of genetic correlations for pulp yield (or cellulose content) with diameter and basic density were available. Estimates of genetic parameters for solidwood traits were also uncommon in the literature. -
Wood properties and stem diameter of Pinus radiata in New Zealand: Genetic parameter estimates of clonal and seedling material
Kumar, S. ; Burdon, R. D. ; Stovold, G. T.
Two genetic trials were sampled in order to study variation and inheritance of wood properties and diameter at breast height in Pinus radiata D. Don. The study involved: (1) Five female testers with 56 pollen parents, c. five individuals per full-sib family, at ages 8 and 13 years; and (2) 33 pair-crosses (from 33 parents) ž 10 clones /cross ž six ramets/clone, at age 8-9 years. Sampling was at one site for each trial. Wood properties studied, directly or indirectly, were density, acoustic velocity, longitudinal shrinkage, collapse on drying, and resin pockets (as resin bleeding). Coefficients of variation for density, velocity. and diameter at breast height were 7%, 11%, and 13%, respectively (rounded to nearest whole number). Estimated broad-sense heritabilities (H2) around age 8 were ?0.6 for all wood properties except resin bleeding, but narrow-sense (h2) estimates were much lower for all traits except density. For diameter at breast height estimated h2 and H2 were ?0.25 and ?0.3 respectively. Diameter at breast height showed generally adverse genetic correlations with wood properties. Notable genetic correlations between wood properties involved density and collapse (rg -0.3 to -0.6). Even allowing for indirect measures of traits, and generally adverse genetic correlations with diameter at breast height, the prospects for genetic improvement of the wood properties are encouraging -
Breeding for wood quality and profit in Pinus radiata: A review of genetic parameter estimates and implications for breeding and deployment
Wu, H. X. ; Ivkovic, M. ; Gapare, W. J. ; Matheson, A. C. ; Baltunis, B. S. ; Powell, M. B. ; McRae, T. A.
We surveyed 55 genetic studies published from 1960 to 2007 involving 11 growth-, form-, and wood-quality traits in Pinus radiata D. Don, including seedling and clonal trials. Estimated genetic parameters evidently varied according to populations, environments, and ages. Overall, estimated heritability for wood-quality traits (except shrinkage) was always higher than for growth and form traits. Wood density had the highest grand-mean of estimated heritability (0.63) among the six wood-quality traits, followed by microfibril angle (0.61), spiral grain (0.55), fibre (tracheid) length (0.54), stiffness (0.50), and shrinkage (0.20). Selective breeding for these wood-quality traits (except shrinkage) would be very effective. Among the five growth and form traits, branch cluster frequency had the highest heritability (0.35), followed by branch size (0.27), branch angle (0.25), diameter at breast height (0.23), and stem straightness (0.23). Broad-sense heritability estimates were higher than narrow-sense heritability, particularly for diameter at breast height (average 0.39 versus 0.21). This indicates there is considerable non-additive genetic variance that should be exploited in breeding and deployment programmes for P. radiata. There was a higher and more complex genotype by environment interaction (G x E) for diameter at breast height in Australian sites than in New Zealand sites. Growth rate (dbh) was adversely correlated with all wood-quality traits (for both density and mean stiffness rg = -0.48). Breeding for overcoming or at least coping with adverse genetic correlations and effective utilisation of non-additive genetic variation are two of the most challenging issues in the advanced generations of P. radiata tree improvement and deployment programmes -
Improving the relevancy of breeding for wood quality in Pinus radiata
Sorensson, C. T.
Improving wood quality of softwoods using selective breeding (Family" or "Varietal Forestry") will improve the efficiency of plantation pine forests at meeting future society's fibre needs, providing improved material is deployed into forests on a sufficient scale. Only by such deployment does wood quality breeding become practically relevant. Although breeding for wood quality is not without its challenges, there are many reasons to attempt it, and some genetically improved material already exists. Unfortunately some foresters hesitate to pay price premiums for such improved planting stock. One issue is that wood qualities such as log velocity may not benefit growers if they are used only to audit whether a log may remain in a visual structural grade or be downgraded. Some processors already have mechanisms for sharing added value of high log velocity with growers, and such mechanisms should gain widespread acceptance over time. Breeders can help by providing clear examples to growers and processors of the wood quality improvements possible from genetic selection through to crop maturity, and of the resulting value impacts on stumpage and through processing. A new series of proposed demonstration forests, Forest+, would also help by showcasing to investors and policy makers the very best plantation forest practices. These plantings would naturally utilise the best silviculture and genetics, and present financial returns couldbe assessed regularly. Greater net incomes possible through the use of elite '2Q' (quantity & quality) genetics will help forestry compete with intensive animal production systems such as dairy that drive current deforestation trends in New Zealand" -
Near-infrared spectroscopy: A rapid non-destructive method for measuring wood properties and its application to tree breeding
Schimleck, L. R.
Near-infrared (NIR) spectroscopy provides a rapid, non-destructive method for the routine estimation of wood properties. NIR spectroscopy is increasingly being used to replace traditional methods of wood property assessment, and it provides a wealth of information to tree growers, tree breeders, and manufacturers of forest products. The technology is particularly well-suited to tree improvement programmes where large numbers of samples must be analysed, but it can be utilised in any forestry application where the rapid provision of wood property data is required. The application of NIR spectroscopy to samples ranging in size from milled chips representing whole trees, to sections of wooden strips cut from increment cores, and, at the smallest scale, to wafers cut from the tangential face of cores was examined, along with studies that have utilised NIR spectroscopy for tree breeding purposes. The technology has some limitations and there are also obstacles to wider acceptance -
Breeding for wood quality - A perspective for the future
Verryn, S. D.
A challenge for tree breeders and wood quality researchers of today is to respond appropriately to a complex environment demanding more productivity, higher quality, and a quicker adaptation of their crops to rapid changes. This is mirrored in the typical modern commodity trends of the need for increasing quality, decreasing costs, and of increasing rate of change of the markets, surrounding technologies, and the environment. The result of such demands is that tree breeders are faced with a growing shopping list" of traits for which to breed, and in a shorter time period. This is a perilous situation, because, as the list of selection criteria increases, so too does the size of the breeding effort increase, or alternatively, the breeder may have to reduce the level of improvement in the traits. This problem is accentuated in the clonal situation, where the market expects all criteria to be met in a single genotype. In a recent study, with the selection target of only four traits, one tree met all criteria in a trial of 475. In another exercise, zero trees were found to be in the top 20% for all four selection traits in 773 trees. Further to these traits, there was a need to select for rooting ability and resistance to various diseases. This highlights the need to model and understand the impact of multi-trait selection on clonal breeding strategies. Future breeding developments are likely to: (1) limit selection traits to those anticipated to be required regardless of changing needs, and weight them in consideration of the associated risks of changing needs; (2) design strategies and adopt technologies which will enable more effective selection of multiple traits; and (3) adopt strategies which will allow effective response to the rapidly changing market, technological, and natural environments. Challenges for wood specialists in response to the above scenarios may be to: (1) identify a few "generic" traits, likely to robustly address a spectrum of possible needs of the future; (2) provide cost-effective early screening techniques (biotechnology may compete here); and (3) develop technologies which will enable effective deployment (e.g., matching the predicted phenotype to the site). The objective is to match the realised phenotype (as a result of genetic and environmental influences) to the processing needs" -
Special issue - Breeding for wood quality
Harwood, C.