Assessment of crown woody biomass in <Emphasis Type="Italic">Eucalyptus grandis</Emphasis> and <Emphasis Type="Italic">E. globulus</Emphasis> plantations

Young trees were harvested to explore non-destructive methodologies to estimate live branch dry weights in young fast-growing Eucalyptus species under different spacing and fertilizer treatments. Branch growth can vary with silvicultural management such as spacing, fertilizing and thinning, and over relatively short periods in response to environmental conditions. Many published regressions based on standard measurements of height and diameter are site, age and treatment specific. The aim of this study was to improve our capacity to predict woody crown dry weight, based on stem measurements, and to minimize (or eliminate) treatment effects on the resulting model. In young trees, branches are temporary support structures for foliage and are often discarded as the base of the green crown rises. As temporary structures they represent an investment of biomass and nutrient elements, and are subject to selection pressures to maximize the return on investment by the tree. Trees were harvested from existing plantation experiments located in south-eastern Queensland for E. grandis W. Hill ex Maiden (ranging from 0.28 to 15.85 m in height, to 5 years old) and south-western Australia for E. globulus Labill. (0.10–34.4 m in height, to 10.2 years) in order to examine the impact of spacing, nitrogen and phosphorus fertilization on early growth. Relationships to estimate crown woody biomass from non-destructive measurements were developed, and these relationships tended to have different slopes and intercepts for trees with predominantly juvenile foliage and those with intermediate or adult foliage. Dry weight of whole-crown live branch wood (W_branch) was related to heights and/or diameter at breast height (D_BH), but the regressions parameters were different, depending on treatment. The relationships became more generic (i.e. less dependent on treatment effects) between W_branch and stem sectional area at the height of the base of the green crown (SA_CB), consistent with the pipe model theory (R² > 0.91 for the two species for trees with intermediate/adult leaves). However, W_branch was more closely related again to the stem volume above the base of the green crown and treatment effects were not significant (V_Con,gc, R² > 0.93). Branches exit the stem below the green crown, and for E. grandis the best relationship was on stem volume above the lowest live branch (V_Con,llb, R² 0.94). Limited sampling from four other species with similar or contrasting crown characteristics indicated that the relationship could be applied quite generally. Individual E. grandis branch woody dry weight was closely related to the conical volume of the main (first order) branch (V_con,br, R² 0.98₎. The whole crown equivalent, branch woody dry weight plus stem dry weight above the lowest live branch, was also closely related to the stem volume within the woody crown (V_Con,llb, R² 0.97–0.99). While the slope of this relationship was still significantly different between trees with juvenile and intermediate/adult foliage, it had a similar form, suggesting that trees with juvenile foliage allocated a different proportion of their woody biomass within the crown to branches than older trees.     

A case study of <Emphasis Type="Italic">Eucalyptus globulus</Emphasis> fingerprinting for breeding

• Introduction  

Tree genetic improvement programs usually lack, in general, pedigree information. Since molecular markers can be used to estimate the level of genetic similarity between individuals, we genotyped a sample of a Portuguese Eucalyptus globulus breeding population—a reference population of 125 individuals—with 16 microsatellites (SSR).     

Non-aerated liquid culture promotes shoot organogenesis in <Emphasis Type="Italic">Eucalyptus globulus</Emphasis> Labill

Eucalyptus is very recalcitrant to in vitro culture. In this research, an efficient shoot organogenesis system was developed using 60-day-old plants of Eucalyptus globulus grown in vitro and non-aerated liquid medium to improve shoot proliferation. Cultures were initiated with hypocotyls and leaf segments from plantlets cultivated on semisolid ½ MS modified medium supplemented with 4.44 µM 6-Benzyladenine (BA) and 16.1 µM 1-Naphthaleneacetic acid (NAA). Calli were transferred to shoot induction medium, with either 0.5 or 2.7 µM NAA. Shoot multiplication was carried out on 4.44 µM BA + 0.5 µM NAA medium, and semisolid and non-aerated liquid systems were compared for improving shoot proliferation. Rooting of adventitious shoots was evaluated on medium containing NAA or Indole-3-butyric acid -IBA (5 and 16 µM). Callogenesis was obtained from both types of explants, although shoot formation was only obtained from leaf-derived calli. Shoot proliferation on 4.44 µM BA + 0.5 µM NAA resulted in the most shoots/callus. Non-aerated liquid medium was more efficient in promoting shoot multiplication (53.5 shoots/callus) than was semisolid medium (28.5 shoots/callus). Levels of phenolic compounds were significantly reduced in the shoots cultivated in liquid medium. Efficient rooting (76%) was obtained using 16 µM IBA.     

Long-term response to area of competition control in <Emphasis Type="Italic">Eucalyptus globulus</Emphasis> plantations

Numerous studies have quantified the responses to vegetation management in Eucalyptus plantations but most publications have reported early responses in tree growth and a gap in knowledge exist about the magnitude and duration of growth responses throughout the whole rotation. We evaluated the long-term response (9 years-old) of E. globulus across a gradient of sites to different intensity levels of free area of competing vegetation around individual tree seedlings. Competing vegetation intensity levels considered free areas ranging between 0 (control) to 2.54 m² plus a treatment with total weed control. Competing vegetation biomass production during the first growing season was 2.9, 6.5, 2.2 and 12.9 Mg ha^?1, for sites ranging from low to high annual rainfall. Across sites, maximum response in stand volume ranged between 58 and 262 m³ ha^?1 at age 9 years and was proportional to the amount of competing biomass controlled during the first growing season. Total competing vegetation control showed the largest response in stand volume at sites with 2.9 and 12.9 Mg ha^?1 of competing vegetation. However, the 2.54 m² vegetation control treatment showed the maximum response for sites with 2.2 and 6.5 Mg ha^?1 of competing vegetation. The duration of response for vegetation control treatments ranged between 5 and 9 years. However, at the site with the largest accumulation of competing vegetation biomass the response to vegetation control showed a sustained and divergent response. Our results suggest that vegetation control improved site resources acquisition increasing long-term stand productivity by reducing environmental limitations to tree growth differentially at each site.     

Genetic variation in heartwood properties and growth traits of <Emphasis Type="Italic">Eucalyptus bosistoana</Emphasis>

Forty-one E. bosistoana families were evaluated for the production of heartwood quantity and quality in two sites. High estimated heritabilities of heartwood diameter (HWD) were found in both sites (0.66 and 0.71). The estimated heritabilities of extractives content (EC) were lower with 0.16 and 0.25. Weak genetic correlations between HWD and EC were found in one site, but highly negative (??0.86) genetic correlations were observed in the other. The G?×?E interaction had no significant influence on growth traits but a small-level influence on the EC. Five families were selected for tree breeding as they produced both large HWD and high EC in both sites. It was suggested that genetic breeding selection could improve the heartwood quantity and quality of E. bosistoana plantations.     

Establishment of native <Emphasis Type="Italic">Eucalyptus pauciflora</Emphasis> and exotic <Emphasis Type="Italic">Eucalyptus nitens</Emphasis> on former grazing land

The success of tree plantings in agricultural landscapes within dry and variable rainfall regions is often below expectations. The aims of this study were to investigate techniques for establishing a local native species (Eucalyptus pauciflora) and an exotic species (E. nitens) in the Midlands of Tasmania, a tree-denuded region that has been grazed for over 100 years in Australia. We established trials at the Sorrel Springs and Woodland Park properties. We compared six establishment techniques: control; understorey nurse planting; spot burn; mulch; tree-guard and; self-watering tree-guard. Three months, 1 and 6 years after planting we measured tree height, health index and mortality. At Sorrell Springs tree-guarded treatments had greater height than other treatments at year one, but there were no effects of treatment at year six on height, health or mortality. At Woodland Park mulch, burn and tree-guarded treatments had greater height 1 and 6 years after planting. At year six tree-guarded treatments had lower mortality than other treatments. At Sorrell Springs height of E. nitens was greater than E. pauciflora at year one but not at year six. At Woodland Park height of E. nitens was generally greater at year six but having almost double the incidence of mortality relative to E. pauciflora. We conclude that expensive tree-guarding is only warranted where high browse pressure is expected and that on such sites species with tough leaves that are resistant to browsing should be considered. Further that in environments marginal for growing trees, best practice establishment technique is generally as effective as additional treatments of understorey nurse planting, spot burning or mulching.     

Effects of inbreeding on population mean performance and observational variances in <Emphasis Type="Italic">Eucalyptus globulus</Emphasis>

• ? Mean performance and variances were studied in self (SELF), open pollinated (OP) and unrelated polymix (POL) crosses of common parentage in Eucalyptus globulus.
• ? Inbreeding depression for survival (SURV) and basal area per hectare (BAH) was the highest reported for a SELF eucalypt population, increasing with age to reach 74 and 77%, respectively, over 10 years.
• ? Inbreeding depression in the OP was 36% for SURV and 32% for BAH at age 10 years, and estimates of outcrossing rate from BAH were stable across ages, averaging 0.56. In contrast, OP inbreeding depression for stem diameter (DBH) of survivors decreased with age and few selfs appeared to survive to 10 years.
• ? There was more variation in DBH between and within SELF than POL families, with variance ratios consistent with rare and partially recessive deleterious alleles causing inbreeding depression.
• ? The OP variances were initially more similar to the SELF population but converged to the POL population after 10 years.
• ? It is argued that when outcrossing rates are low, as in the present case, inbreeding depression will be a significant force countering local adaptation in forest trees.

     

Sequencing and quantifying plastid DNA fragments stored in sapwood and heartwood of <Emphasis Type="Italic">Torreya nucifera</Emphasis>

The selection of wood species and the styles of sculpture play key roles in the characterization of Buddhist statues. After Jianzhen, a Chinese Buddhist monk, visited Japan in the mid-eighth century, wood of the genus Torreya had been frequently used to produce single-bole statues. Establishing measures for the accurate identification of wood in the genus Torreya is effective for investigating the drastic change in the production of statues during this period. Analyzing the plastid deoxyribonucleic acid (DNA) fragments extracted from wood is considered helpful in the identification of species in the same genus. This study analyzed the sequences and residual amounts of plastid DNA fragments in the wood of Torreya nucifera. Nucleotide substitutions in the plastid DNA were clearly identified between T. nucifera and the species distributed in China, indicating that the wood of Torreya sp. can be discriminated based on the plastid DNA sequences. DNA polymorphism analyses revealed sequence diversity for the intergenic spacers on the T. nucifera plastid DNA. A series of polymerase chain reaction (PCR) analyses demonstrated that the plastid DNA fragments with a length of approximately 100 bp could be amplified from the residual DNA extracted from the T. nucifera sapwood with longer elapsed years after cutting. Therefore, an identification of wood species in the genus Torreya based on their plastid DNA is considered to be one of the most effective measures taken in the study regarding the historical changes of Buddhist statues.     

Successful <Emphasis Type="Italic">Agrobacterium</Emphasis>-mediated transformation of <Emphasis Type="Italic">Populus tomentosa</Emphasis> with apple <Emphasis Type="Italic">SPDS</Emphasis> gene

The problem of salinized soils has become one of the most serious constraints to agricultural and forest productivity. With the purpose of enhancing salt stress tolerance of Populus tomentosa, we transformed this tree species with spermidine synthase （SPDS） genes derived from an apple by an Agrobacterium-mediated method. Four transgenic clones were confu＇med by PCR and Southern blot analysis. As well, the expression of introduced SPDS genes was analyzed by real-time quantitative PCR.     

Characteristic Raman bands for <Emphasis Type="Italic">Artocarpus heterophyllus</Emphasis> heartwood

The Raman spectrum of Artocarpus heterophyllus heartwood, which proved to be a rich source of flavonoids, exhibited two characteristic bands, at 1247cm^–1 and 745cm^–1. The bands also appeared in the Raman spectrum of the yellow-brown needles extracted from the heartwood with methanol. Based on the Raman measurements of flavones and related compounds, it was predicted that the Raman band at 1247cm^–1 may be attributed to flavonoid-type compounds. No vibrational band corresponding to the characteristic Raman bands was observed by diffuse reflectance infrared spectroscopy. Thus, it was suggested that observation of the characteristic bands is an advantage of Fourier transform-Raman spectroscopy for nondestructive analysis of wood.     

Weeds in <Emphasis Type="Italic">Eucalyptus globulus</Emphasis> subsp. <Emphasis Type="Italic">maidenii</Emphasis> (F. Muell) establishment: effects of competition on sapling growth and survivorship

The effect of herbaceous vegetation on growth and survival was assessed in planted eucalyptus saplings grown under four levels of weed cover. Seedlings of Eucalyptus globulus subsp. maidenii were planted with 0 (W0), 25 (W25), 50 (W50) and 100% (W100) weed cover. Weed species composition and aboveground biomass was determined. Soil water content was evaluated by the gravimetric method. Seedling leaf area, diameter and height were evaluated at planting and during the 3 months following establishment. Tree height, diameter and stem volume was estimated at 12, 24 and 36 months. First year tree survival was recorded. The ratio of cumulative stem growth under W100: cumulative stem growth under W0 was used to measure competitive performance. Regression analysis was used to determine competition thresholds. Weeds seriously threaten the growth of E. globulus subsp. maidenii. Early negative effects of competition on growth were evident as from the second month after establishment, and both seedlings and 1-year-old saplings were more affected than 2- and 3-year-old ones. A “minimum-response threshold” was determined near 500 kg/ha (corresponding to W25 cover). No clear effect was found between sapling survival and weed biomass.     

Insecticidal properties of <Emphasis Type="Italic">Thymus persicus</Emphasis> essential oil against <Emphasis Type="Italic">Tribolium castaneum</Emphasis> and <Emphasis Type="Italic">Sitophilus oryzae</Emphasis>

Red flour beetle Tribolium castaneum (Herbst) and rice weevil Sitophilus oryzae (L.) are considered to be the major insect pests in storage. Essential oils from aromatic plants are recognized as proper alternatives to fumigants. Thymus persicus (Ronniger ex Rech. f.) is one of these plants that have medicinal properties and is indigenous to Iran. The essential oil was obtained from aerial parts of the plant and analyzed by GC and GC–MS. Carvacrol (44.69%) and thymol (11.05%) were the major constituents of the oil extracted. In this experiment, fumigant toxicity of the essential oil was studied against T. castaneum, S. oryzae at 27 ± 1°C and 60 ± 5% RH in dark condition. The adult insects were exposed to the concentrations of 51.9, 111.1, 207.4 and 370.4 μl/l air to estimate median lethal time (LT₅₀) values. The fumigant toxicity was increased in response to increased essential oil concentrations. The LT₅₀ values at the lowest and the highest concentrations tested were ranged from 28.09 to 13.47 h for T. castaneum, and 3.86 to 2.30 h for S. oryzae. It was found that S. oryzae adults were much more susceptible to the oil than T. castaneum. After 24 h of exposure, the LC₅₀ values (95% fiducial limit) for T. castaneum and S. oryzae were estimated to be 236.9 (186.27–292.81) and 3.34 (2.62–4.28) μl/l air, respectively. These results suggest that T. persicus essential oil merits further study as potential fumigant for the management of these stored-product insects.     

Antifungal agents from heartwood extract of <Emphasis Type="Italic">Taiwania cryptomerioides</Emphasis> against brown root rot fungus <Emphasis Type="Italic">Phellinus noxius</Emphasis>

Taiwania (Taiwania cryptomerioides Hayata) is a native and plantation species in Taiwan, and its heartwood has demonstrated excellent decay resistance. Brown root rot fungus Phellinus noxius has caused severe damage to more than 100 tree species in Taiwan. The aims of this study were to investigate the antifungal activities of Taiwania heartwood extracts against P. noxius and to identify the antifungal compounds. Antifungal activities were examined using the agar dilution method (a direct contact assay) and the inverted lid method (a vapor contact assay). Active compounds were purified using liquid–liquid partition, open-column chromatography and HPLC. Among four soluble fractions (n-hexane, ethyl acetate, n-butanol and water soluble fractions), results showed that n-hexane soluble fraction (HSF) can significantly inhibit the growth of P. noxius via the agar dilution method. Moreover, active compounds present in HSF were obtained using antifungal assay-guided fractionation. Results showed that ferruginol, T-cadinol, α-cadinol and T-muurolol were found to exhibit excellent antifungal activities against P. noxius, and their IC₅₀ values were 16.9, 25.8, 33.8 and 50.6 μg/mL, respectively. According to the current findings, phytochemicals (ferruginol, T-cadinol, α-cadinol and T-muurolol) of Taiwania heartwood had the potential to be used as environmentally benign antifungal agents against P. noxius in place of synthetic or inorganic fungicides.     

Response of <Emphasis Type="Italic">Eucalyptus camaldulensis</Emphasis> and <Emphasis Type="Italic">Acacia mangium</Emphasis> kraft pulp in different ECF bleaching options

In this study, the response of Eucalyptus camaldulensis and Acacia mangium kraft pulp to different options of ECF bleaching was investigated. Oxygen-delignified pulps of both species having similar kappa number (c.a. 12) were used. Both the pulps were prebleached using conventional ClO₂ stage (D₀), combined use of ClO₂ and O₃ (DZ), hot acid treatment before D₀ (A_hotD₀) and hot acid treatment before (DZ) i.e., A_hot(DZ), hot ClO₂ treatment (D_HT) and A_hot followed by D_HT (A_hotD_HT). All prebleached pulps were finally bleached to 90%+ ISO brightness using D₁ option. The overall benefits of other options were not considerable compared to D₀ and (DZ). From the ClO₂ consumption point of view, for a certain species, the option A_hot(DZ) was the best. Instead of D₁ in final bleaching, pressurized hydrogen peroxide (PO) was also investigated in the case of D₀ and (DZ) prebleached pulps. (PO)-bleached pulp produced higher brightness stability but lower viscosity compared to D₁.     

Understanding the naturalization of <Emphasis Type="Italic">Eucalyptus globulus</Emphasis> in Portugal: a comparison with Australian plantations

Despite the potential utility of a biogeographical approach to understanding the naturalization of exotic species, studies using this approach are scarce. Eucalyptus globulus is an economically important Australian tree species that has become naturalized in a number of countries where it was introduced. Portugal is an ideal territory to study the naturalization of E. globulus owing to: a long introduction history, the antipodal location compared to Australia and the large cultivated area. Wildling density was assessed in 116 E. globulus plantations in central Portugal through 213 transects established along plantation borders. Boosted regression trees were used to model the influence of plantation-scale variables. Results from this survey were compared with data obtained in plantations from seven Australian regions, where a similar sampling protocol had been used. In Portugal, wildlings were more abundant in plantations that were: located in moist aspects, coppiced, with older tree stems and corresponding to intermediate site growth indexes. The overall density (127 plants ha^?1) was 14.9 times higher than in the Australian estate, but this ratio was reduced to 3.1 in a more comparable subset of unburnt, first rotation plantations. A generalized linear model fitted using a dataset combining the two surveys showed that country influenced wildling density, together with plantation rotation and stem age. These results provide insights into the naturalization of a widely cultivated tree species, pointing to a fundamental role of the introduction history, possibly acting along with the biogeographical characteristics of the introduced range.     

Extractives of <Emphasis Type="Italic">Quercus crispula</Emphasis> sapwood infected by the pathogenic fungi <Emphasis Type="Italic">Raffaelea quercivora</Emphasis> I: comparison of sapwood extractives from noninfected and infected samples

The extracts of Quercus crispula infected by the ambrosia fungus, Raffaelea quercivora, were investigated. Phenol and tannin analyses indicated that normal sapwood (NS) contained a considerable amount of hydrolysable tannins, while infected colored sapwood (IS) contained less hydrolysable tannins and more phenols than NS. In treating pentagalloyl glucose (PGG), which is a model compound of hydrolysable tannins, with a culture medium of R. quercivora, PGG was rapidly hydrolyzed to produce gallic acid. The resulting gallic acid decreased in concentration over the subsequent cultivation period eventually disappeared. Measuring tannase and laccase activities of the culture medium of R. quercivora, tannase activity increased gradually from the beginning, while laccase activity increased rapidly at 5 days of incubation and disappeared at 8 days. An oxidative product from gallic acid treated with laccase was isolated by preparative high performance liquid chromatography, and was identified as purprogallincarboxylic acid (PGCA) by nuclear magnetic resonance spectroscopy and electron-impact mass spectrometry. PGCA was present in a 70% aqueous acetone extract of IS, and showed slight growth inhibition against R. quercivora. Part of this study was presented at the 57th Annual Meeting of the Japan Wood Research Society, Hiroshima, Japan, 2007     

Bioremediation of CCA-treated wood by brown-rot fungi <Emphasis Type="Italic">Fomitopsis palustris</Emphasis>, <Emphasis Type="Italic">Coniophora puteana</Emphasis>, and <Emphasis Type="Italic">Laetiporus sulphureus</Emphasis>

This study evaluated oxalic acid accumulation and bioremediation of chromated copper arsenate (CCA)-treated wood by three brown-rot fungi Fomitopsis palustris, Coniophora puteana, and Laetiporus sulphureus. The fungi were first cultivated in a fermentation broth to accumulate oxalic acid. Bioremediation of CCA-treated wood was then carried out by leaching of heavy metals with oxalic acid over a 10-day fermentation period. Higher amounts of oxalic acid were produced by F. palustris and L. sulphureus compared with C. puteana. After 10-day fermentation, oxalic acid accumulation reached 4.2 g/l and 3.2 g/l for these fungi, respectively. Fomitopsis palustris and L. sulphureus exposed to CCA-treated sawdust for 10 days showed a decrease in arsenic of 100% and 85%, respectively; however, C. puteana remediation removed only 18% arsenic from CCA-treated sawdust. Likewise, chromium removal in F. palustris and L. sulphureus remediation processes was higher than those for C. puteana. This was attributed to low oxalic acid accumulation. These results suggest that F. palustris and L. sulphureus remediation processes can remove inorganic metal compounds via oxalic acid production by increasing the acidity of the substrate and increasing the solubility of the metals.An erratum to this article can be found at     

Enzymatic saccharification and ethanol production of <Emphasis Type="Italic">Acacia mangium</Emphasis> and <Emphasis Type="Italic">Paraserianthes falcataria</Emphasis> wood,and <Emphasis Type="Italic">Elaeis guineensis</Emphasis> trunk

We examined the saccharification and fermentation of meals from Acacia mangium wood, Paraserianthes falcataria wood, and Elaeis guineensis trunk. The levels of enzymatic hydrolysis of cellulose and ethanol production were highest for P. falcataria wood and lowest for A. mangium wood. Ultrasonication pretreatment of meal further increased the rates of hydrolysis and ethanol production in meal from P. falcataria wood. Through this pretreatment, hemicelluloses (xylan and xyloglucan) and cellulose were released in the meal from P. falcataria wood. Loosening of hemicellulose associations can be expected to make P. falcataria wood more useful for bioethanol production.     

Carbon in heartwood,sapwood and bark along the stem profile in three Mediterranean <Emphasis Type="Italic">Pinus</Emphasis> species

• Context   

Understanding biological processes in forests is necessary to orientate ecosystem management towards potential C sequestration. To achieve this, information is required about changes in forest biomass C pools, including the stem components (bark, sapwood and heartwood).