Dissertations / Theses: 'Pinus radiata'

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Waghorn, Matthew J. "Effect of initial stand spacing and breed on dynamic modulus of elasticity of Pinus radiata." Thesis, University of Canterbury. Forestry, 2006. http://hdl.handle.net/10092/1129.

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Wood stiffness or modulus of elasticity (MOE) is one of the most important wood properties for solid timber applications, and as such, the efficacy of wood use, especially for structural timber is strongly related to MOE. MOE in Pinus radiata is highly variable and poorly understood. In this study, the effect of initial stand spacing and breed on outerwood MOE and the vertical distribution of MOE of Pinus radiata was assessed. Understanding positive or negative influences of growth caused by initial stand spacing and genetic material on MOE is appealing because it could enable us to better comprehend how forest growers could adapt silvicultural operations to the demands of wood processing. Physical characteristics of different breeds and propagation methods of Pinus radiata were assessed at a variety of initial stand spacings. Stem diameter, crown height, stem slenderness and branch size were all heavily influenced by stand spacing. Breed had a marginally significant influence on diameter and stem slenderness. Internode length was not affected by stand spacing, but showed sizeable differences, especially between the long internode 870 breed and the remaining growth and form (GF) breeds. Outerwood MOE was significantly (P<0.0001) influenced by stand spacing and breed, but not their interaction (P>0.05). MOE scaled positively with stand spacing. MOE increased by 39% from 5.4 GPa at 209 stems ha-1 to 7.5 GPa at 2551 stems ha-1. The majority of this increase (33%) occurred between 209 and 835 stems ha-1. Physiologically aged cuttings of greater maturation status exhibited greater MOE, with the three-year-old cuttings being stiffer than the one-year-old cuttings, seedlings from the 870, 268 and 850 series, by 15, 17, 22 and 27%, respectively. Stem slenderness exhibited the strongest significant (P<0.0001) relationship with MOE (r2=0.49), followed by green crown height (r2=0.46) and diameter (r2=0.44). Stem slenderness and green crown height had a direct influence on MOE that explained 53% of the variance in MOE. MOE was also significantly (P<0.0001) influenced by spacing and breed when using the resonance technique to assess whole stem MOE. The vertical distribution of MOE showed that the lowest portion of the stem (bolt 1) was approximately 30% less stiff than bolts 2 and 3. After the greatest MOE value had been obtained at bolt 3, MOE gently declined to the top of the measured stem. Variation of MOE within trees was significant (58%) at the high stockings of 1457 and 2551 stems ha-1, but somewhat lower (36%) at the lower stockings. The 870 breed was approximately 8% and 16% stiffer than the 268 and 850 breeding series respectively, across all stockings, with the three-year-old cuttings being 7% stiffer than the one-year-old cuttings. At stockings of 481 stems ha-1 and less, the proportional height at which MOE was greatest within a tree was between 25% and 50% of stem height. At stockings above 481 stems ha-1 the proportional height at which maximum MOE was obtained was between 15% and 40% of stem height. Bolt slenderness was found to be the most significant factor impacting on MOE of the bolt. Regression of critical buckling height against diameter at ground level yielded a scaling exponent of 0.55, which was lower than the scaling exponent of 0.67 predicted with constant density-specific stiffness. There was a tendency for some bolts with lower mean diameter to display significantly higher safety margins than bolts with higher mean diameter, suggesting that the largest bolts, which occur at the base of tree, are the point of most likely critical failure.

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Tang, Samuel Y. Y. "Modeling the mechanical properties of Pinus Radiata." Thesis, University of Canterbury. Mechanical Engineering, 1998. http://hdl.handle.net/10092/6420.

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The study of a methodology to model the mechanical properties of Pinus Radiata takes place from the nanoscopic cell fiber [3] to the board scale level. Gibson and Ashy had generalized wood cells into hexagonal cells, previous work [2] extends the model specifically for Pinus Radiata. Unfortunately, earlier work was done on published data from various sources, not necessary related to Pinus Radiata nor from a common reference piece of characterized Pinus Radiata, making correlation with experimental work [4] difficult. Further work was done by the author on a characterized sample of Pinus Radiata to correlate elastic properties with actual cellular geometry and experimental result. Critical geometrical parameters were studied for a feasible mathematical idealization as necessary parameters to further refine the FEM model. Two approaches were used in evaluating board scale modeling; actual wood cells geometry and idealized hexagonal models. These models are extended to Growth ring model to predict growth ring mechanical properties and validated with experimental results as a preliminary Board scale model. Stol had modeled Wood cells as hexagonal cellular material using Gibson's [1] analytical solution in his work with orthotropic wood wall's properties [2]. Sto1's analytical solution neglects the longitudinal dimension, which in realism is closer to plate than beam. Gibson and Asbhy's work on prediction of cellular properties analytically formed the basis of formulation analytical solution using energy method (Ritz's method) with plate type stiffness function and further extended with shear and longitudinal boundary coupling effect. The plate analytical solution was validated by FEM to be in close agreement, within a 5% error. The model based on real cell geometry and its equivalent regular array of identical cell has broad agreements with experimental values. Further refinements of this model are important steps in the development of a definitive model. Preliminary work on a growth ring FEM model is important as part of the preparation for a board scale model, however further refinements would be necessary for definitive board scale FEM model.

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Li, Guizhen. "Wood structure and properties of clonal plantlets and seedlings of Pinus radiata." Thesis, University of Canterbury. Plant and Microbial Sciences, 2000. http://hdl.handle.net/10092/5927.

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The ontogeny of vascular cambium and the wood formation in the 8 month-old Pinus radiata have been examined. The results showed that the procambium develops from the subapical meristem parenchyma, which is converted to pro cambial cells by periclinal division about 0.5 mm from the shoot tip. The interfascicular cambium originates from the interfascicular parenchyma, which is also derived from the subapical meristem. Transverse sections show that the interfascicular parenchyma convert to interfascicular cambial cells requires activation by the fascicular cambium. The vascular cambium was established by the fascicular cambium connecting with the interfascicular cambium. Compression wood formation is related to the plantlet's response to stress. The magnitude and distribution of compression wood is related to whether the stem is free-growing, staked vertically, or tied to an inclined stake, the three situations generating 27%, 14% and 49% compression wood as assessed by image analysis of thin sections. Stiffness, density, tracheid length, cell numbers/mm2, and percent cell wall area were tested for plantlets of clones 8 and 31 grown under three treatments. Compared to the free grown plantlets, the angled plantlets were shorter, thinner, contained more compression wood with thicker cell walls and more cells/mm2, and had shorter denser tracheids to formed weaker wood. By contrast the tied plantlets were taller and thinner, having fewer cells/mm2 with each tracheid being longer and less dense (thinner cell walls), but of similar stiffness to the free grown ones. Compression wood was stiffer than opposite wood because of its higher density, and the angled plantlets were weaker than the free and tied plantlets due to their shorter tracheids. Stiffness is related to density in angled plantlets, and related to tracheid length in the free and tied plantlets. Tracheid length is negatively related to density, cells/mm2, and percent cell wall. Density is related to percent cell wall and cells/mm2, and the percent cell wall and cells/mm2 related each other. Stiffness, microfibril angle, density, and maximum crushing strength have been studied for 1 and 2 year-old seedlings from seedlots 10 and 28. The results indicated that stiffness increased and microfibril angle decreased from one year-old to two year-old material. A relationship between maximum crushing strength and density and a negative relationship between stiffness and microfibril angle existed in two years old plantlets. Stiffness and maximum crushing strength related each other in both one and two years old plantlets. Overall, this work proved to be a scoping trial. While the results could have been anticipated in general terms they do provide a useful description of very young wood. The extent of compression wood varied greatly between treatments, but even in the best case (tied) it takes up a significant proportion of the stem cross-section. However, the technical challenges, especially in the measurement of mechanical properties in such small samples remains a formidable challenge.

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Lin, Xueqin. "Culture of isolated embryos of Pinus radiata D. Don." Thesis, University of Canterbury. Plant Biotechnology, 2000. http://hdl.handle.net/10092/7031.

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Effects of nutritional factors, plant growth regulators, and physical factors on the conversion of isolated embryos into plantlets of Pinus radiata were investigated. Results showed that nutritional factors were critical to the conversion of isolated embryos into plantlets of P. radiata. The optimum medium strength was half strength of the medium consisting of modified Quoirin and Le Poivre (LP) salts (von Arnold and Eriksson 1981) and Schenk and Hildebrandt (1972) (SH) vitamins. Sucrose (3%) as well as glucose (2-3%) and fructose (2-5%) could serve as carbon sources for the conversion of isolated embryos into plantlets of P. radiata. In general, a few significant benefits were found with the addition of organic nitrogen sources tested on the performance of isolated zygotic embryos into plantlets of P. radiata. Nearly all plant growth regulators tested were not beneficial for the conversion of isolated zygotic embryos into plantlets of P. radiata, and some of them had negative effect. Only GA₃ (gibberellic acid at 0.58 μM) seemed to stimulate embryos to germinate a little bit earlier in comparison with the control. Submerging the cotyledons of the isolated embryo into the agar-gelled medium showed better growth in comparison with the control. Embryos cultured in liquid medium grew better but the germination percentage was apparently lower compared with 0.8% agar-gelled medium. liquid medium with sponge support could increase the percentage of germinated isolated embryos but the embryo growth was not comparable to the liquid medium only. The addition of PEG (polyethylene glycol) 6000 to the liquid medium seemed to increase the germination percentage and had no negative effect on the growth of isolated embryo. Light could influence embryo growth in different ways. For root growth, 16-hour photoperiod appeared to be the best, but for cotyledon development continuous light condition seemed to be the best. In continuous darkness, the hypocotyl appeared to elongate more, but the cotyledon and root did not grow well. Isolated embryos cultured on the optimum medium (LPSH2) grew well. The resulting plantlets (i.e. emblings) appeared normal, but were smaller than seedlings. Studies on biochemical changes during germination and early embling or seedling growth showed that the patterns of changes in total protein, soluble sugar, and starch content were generally different between emblings and seedlings. However, on fresh weight basis, total protein concentrations and their SDS-PAGE profiles showed that there was little difference between emblings and seedlings. Results of this study should be helpful as a basic reference for the artificial seed technology development starting from germination and plant conversion of P. Radiate somatic embryo with an artificial megagametophyte.

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Cerqueira, Andreia Filipa Lages. "Effects of phosphite in Pinus radiata-Fusarium circinatum interaction." Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/17015.

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Mestrado em Biologia Molecular e Celular
O cancro resinoso, provocado pelo fungo Fusarium circinatum, é uma doença que afeta Pinus spp. e Pseudotsuga menziesii em todo o mundo e está sujeita a medidas de quarentena. Caracteriza-se pela formação de grandes cancros resinosos que rodeiam rebentos, ramos e troncos e levam à morte do hospedeiro. Até à data não existem meios para o controlo da doença e, com a crescente necessidade de reduzir o uso de fungicidas, outras abordagens devem ser estudadas. Um método para o controlo de doenças fitopatogénicas passa pela indução da resistência do hospedeiro, através do pré-tratamento de plantas com compostos químicos ou de origem biológica que estimulam as defesas. O fosfito (Phi) é um sal inorgânico que apresenta a capacidade de indução da resistência e uma potencial estratégia mais amiga do ambiente. Neste estudo, a utilização do fosfito de potássio (KPhi) na redução do desenvolvimento dos sintomas da doença do cancro resinoso, assim como os seus efeitos no crescimento do fungo, foram estudados em diferentes concentrações. Numa primeira fase, colónias de F. circinatum foram crescidas em PDA suplementado com Phi (0%, 1% e 4%) para avaliação do seu efeito no crescimento radial. Posteriormente foram estudados os efeitos da aplicação foliar de Phi (0%, 1% e 4%) em plântulas de Pinus radiata, inoculadas e não inoculadas. A taxa de sobrevivência e a performance fisiológica (potencial hídrico, trocas gasosas e performance fotoquímica, pigmentos, peroxidação lipídica, libertação de eletrólitos, prolina e carbohidratos) foram avaliados. Os resultados mostram que aplicação de Phi atrasa o desenvolvimento dos sintomas de doença numa forma dependente da concentração de Phi, em semelhança ao observado relativamente à inibição do crescimento do micélio in vitro. Alterações fisiológicas ao nível da prolina e carbohidratos, peroxidação lipídica e trocas gasosas foram observadas. A aplicação de Phi apresenta-se como uma potencial alternativa viável na gestão da doença do cancro resinoso.
The pitch canker, caused by the fungus Fusarium circinatum, is a disease under quarantine measures affecting Pinus spp. and Pseudotsuga menziesii worldwide. Characterized by the formation of large resinous cankers that girdle shoots, branches, and trunks, leads to the death of the host. To date, there are no means for the control of the pitch canker and, with the growing need to reduce the use of fungicides, another approaches must be studied. A method for the control of phytopathogenic diseases is the enhancement of host resistance, through pre-treatment of seedlings with chemicals or biologically derived compounds that stimulate defense responses. Phosphite (Phi) is an inorganic salt with the capability of inducing host resistance and presents an approach more environmentally friendly. In this study, the ability of potassium phosphite (KPhi) in delaying the pitch canker symptom development, as well as its effects in fungal growth, were studied at different concentrations. In a first phase, F. circinatum colonies were grown in PDA medium supplemented with Phi (0%, 1% and 4%) to evaluation in the radial growth of the fungus. Posteriorly, were studied the effects of foliar application of Phi (0%, 1% and 4%) in Pinus radiata seedlings, inoculated and non-inoculated. Survival and physiological performance (water potential, gas exchange and photochemical performance, pigments, lipid peroxidation, electrolyte leakage, proline and carbohydrates) were assessed. Results showed that Phi application delayed disease symptoms in a dose dependent manner similarly to what was observed in mycelial growth inhibition during in vitro assays. Physiological alterations in proline, carbohydrates, lipid peroxidation and gas exchange parameters were observed. Thus, Phi application presents a potential viable alternative to the management of the pitch canker disease.

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Moreno, Chan Julian. "Moisture content in radiata pine wood : implications for wood quality and water-stress response : a thesis submitted in fulfilment of the requirements for the degree of Doctor of Philosophy in Forestry, School of Forestry, College of Engineering, University of Canterbury /." Thesis, University of Canterbury. School of Forestry, 2007. http://hdl.handle.net/10092/1217.

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This thesis studied the influence of moisture content on the dynamic estimation of stiffness in wood of Pinus radiata D. Don. This is an important non-destructive measure for estimation of stiffness in standing trees, logs and lumber. Moisture content affects both acoustic velocity and density in the fundamental equation of dynamic MOE (DMOE = V²ρ, where V = acoustic velocity and ρ = density). Investigation included measurements with boards in the laboratory considering moisture contents below and above FSP as well as temperatures below and above 0°C. This also included field measurements of trees in contrasting climate sites and over different seasons including a long drought. Methods for measuring green density and moisture content and the patterns of variation of these parameters were also investigated. A secondary component of this thesis explored the wood quality and some mechanisms of tree response to water stress in two contrasting sites in terms or rainfall and water deficits in a region of Australia. The large increases in DMOE for frozen wood above the FSP (4.5 to 6 GPa) will limit the use of DMOE for grading logs in regions with freezing winters. Results from the experiment remeasuring young trees and the upper range of moisture content and temperatures above 0°C from the experiment with boards showed small to moderate variation in DMOE (0.1 to 1 GPa) which calls for further investigation on analytical procedures for adjustment of DMOE. Such procedures should consider that variations in acoustic velocity and density with changes in moisture content are not proportional and that there are counteracting effects between the two parameters. It remains to be investigated whether the typical variation (under normal climate conditions) in sapwood green density observed in our experiments has some implications for the use of DMOE. On the other hand, it is anticipated that the large differences along the stem and among stands in whole-section green density may bias DMOE measurements in logs for resource assessment. This also needs to be investigated. A comparison between acoustic velocity alone and DMOE for resource assessment under different scenarios is recommended. The study in two contrasting climate sites (high-altitude vs. warm-dry) in the Hume region of Forests NSW, Australia, including young (10-11 years) and mature trees (34 36 years) of radiata pine showed distinctive short and long-term responses of trees to cope with the water-limiting environment. In response to long-term water deficits the warm-dry site developed heartwood and thus reduced sapwood earlier and at faster rates than the high-altitude site. The onset of heartwood formation seemed to be triggered by some site threshold for water use as broadly indicated by the sapwood area/ha. The latter was consistently lower for the warm-dry site across the different stands. The warm-dry site also showed increased short-term responses to water stress and these were interpreted as seasonal mechanisms of the trees to cope with the limiting environment. The trees compensated for the lower available moisture and higher transpiration rates by lowering their saturation and disrupting water conduction at some points (cavitation). The inverse trends of cavitation spots and cavitation bands with height in the stem suggested the trees have different strategies to sacrifice conducting xylem depending on the position on the stem. Finally, it is suggested that saturation tended to fall to critical 'safe' levels as a result of water stress and this varied depending on age, site, and position in the stem. Significant decreases in DMOE and basic density were observed for the warm-dry site and were attributed to lower proportions of latewood due to lower rainfall for that site during the period of latewood formation. These showed no obvious association with any of the long-term water-stress traits (sapwood percentage and number of heartwood rings).

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Wells, Karen E. "Development of a Laboratory Protocol for the Micropropagation of Monterey Pines (Pinus Radiata), Año Nuevo Stand." DigitalCommons@CalPoly, 2009. https://digitalcommons.calpoly.edu/theses/76.

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Monterey pine (Pinus radiata), a native tree to California and two Mexican islands, is important both ecologically and economically. Outside native stands, Monterey pines are grown for landscaping in California and on plantations around the world. Pitch canker, a disease caused by the fungus Gibberella circinata Nirenberg & O’Donnell (Fusarium circinatum Nirenberg and O'Donnell) is threatening the survival of Monterey pines. The disease currently affects Monterey pines in many parts of the world including the native stands. No effective chemical or biological control is available but some Monterey pines show resistance to the disease. The purpose of this project was to develop a working protocol for producing genetic clones of the resistant pines through micropropagation. These genetic clones will be used for outplanting in places outside the native stands for ornamental and plantation purposes. This project analyzes the results of ten trials with varied parameters and bases the final protocol on the parameters used in the trial that induces the growth of new shoots. The final protocol developed in this project describes, step-by-step, the media preparation for the initiation, plant material collection, surface sterilization of plant material, plating in media and initiation of shoots on explants. The protocol calls for collecting shoot tips with hardened buds that have not yet elongated, then washing the shoot tips in sterile water with Tween 20 for 15 minutes. The shoots tips are then surface sterilized in a 50% bleach solution for 20 minutes. The explants are broken into disks (to minimize damage to the cells) by inserting the tip of a scalpel and tilting it slightly. The initiation media shown to induce growth consists of ½ strength LePoivre basal salt mixture, 5mg/L benzylaminopurine, 3% sucrose and 0.8% agar and is adjusted to a pH of 5.7, then autoclaved for 20 minutes. The explants are inserted into solidified media and incubated in a growth chamber programmed for 16 hours of light and 8 hours of dark with temperatures of 27ºC and 22ºC and light irradiance of 80µEm-2s-1. After 1 month the protocol calls for transferring the growing shoots to elongation media with full LP basal salts and transferring every month. When the number of desired shoots has been reached the forthcoming protocol for rooting can be followed.

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Nanayakkara, Bernadette. "Chemical Characterisation of Compression Wood in Plantation Grown Pinus Radiata." The University of Waikato, 2007. http://hdl.handle.net/10289/2343.

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The primary objective of this study was to find out if changes in chemistry could be used to quantify Pinus radiata compression wood severity or degree of compression wood development. Basic chemical composition and the lignin structure was assessed for a range of different compression wood samples sourced from juvenile wood, mature wood, earlywood, latewood, branches, knots, 2-year and 1-year old Pinus radiata. Fluorescence microscopy was used as the reference method to assess the degree of compression wood development. Lignin structure of compression wood was studied by thioacidolysis, size exclusion chromatography, and thioacidolysis/31P NMR spectroscopy. Variation in the basic chemical composition and lignin structure with compression wood severity was ascertained. Results showed that, as the severity of compression wood changed, progressively from normal through mild to severe, all chemical parameters commonly associated with compression wood changed concurrently. With increasing severity lignin and galactose levels increased while glucose and mannose levels decreased. Lignin structural changes were also associated with changing severity of compression wood. Levels of p-hydroxyphenyl (H) releasable β-ethers increased and guaiacyl (G) releasable β-ethers decreased. Similarly, levels of uncondensed p-hydroxyphenyl units increased, while uncondensed guaiacyl units decreased. Similar proportions of condensed guaiacyl units were present in compression wood and normal wood. Similar trends in chemical composition were observed between the compression wood and related opposite wood in branches, knots and young wood of Pinus radiata. A number of chemical parameters changed linearly with compression wood severity. They were: the amount of lignin and galactose, the galactose/glucose ratio and p-hydroxyphenyl content in lignin. Parameters based on the p-hydroxyphenyl unit content in lignin, the H/G releasable β-ether ratio, releasable p-hydroxyphenyl β-ether units and uncondensed p-hydroxyphenyl C9 units are most suitable indicators of compression wood severity as they spanned a larger range relative to the normal wood levels and were not influenced by the morphological origin of wood samples. Chemical methods for quantifying compression wood severity should focus on the detection and measurement of these parameters. Galactan present in Pinus radiata compression wood was isolated and characterised. Structural investigation by methylation analysis and NMR spectroscopy revealed that this galactan was largely composed of (1→4)-linked β-D-galactopyranose residues. No evidence was found to indicate the presence of any branches. Characterisation of lignin in cell wall fractions of Pinus radiata normal wood revealed that middle lamella lignin has a higher lignin content, a lower amount of releasable β-ethers and a more condensed lignin than the secondary wall lignin. Levels of releasable p-hydroxyphenyl units were not higher in middle lamella lignin. A new method based on thioacidolysis and 31P quantitative NMR spectroscopy for estimation of the degree of lignin condensation of the phenolic and etherified C9 units in in situ wood lignin is described. Using this method it was found that phenolic C9 units in in situ lignin were considerably less condensed than etherified C9 units in both compression wood and normal wood.

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Kay, Stuart James. "The biological control of sapstain of Pinus radiata with microorganisms." Thesis, University of Auckland, 1995. http://hdl.handle.net/2292/2474.

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A total of six hundred and sixteen fungal and two hundred and thirty two bacterial isolates were obtained either from the sapwood of Pinus radiata or from other sources, including UV mutagenesis. All isolates were screened on Pinus radiata wood chips for their survival and colonisation attributes. Of these isolates, two hundred and eighty two failed to grow or caused permanent deep seated discolourations or decay and were eliminated from the study. The remaining five hundred and sixty six isolates were assessed for their antagonistic ability against sapstain. In a dual screen on Pinus radiata wood chips, one hundred and twelve fungal and four bacterial isolates inhibited the growth of the known sapstain fungus, Ophiostoma piceae. In a second biological control screen, on Pinus radiata wood blocks, isolates of Gliocladium viride, Gliocladium roseum, Trichoderma hamatum, Trichoderma harzianum, Trichoderma sp., Trichothecium roseum and an isolate of the Thelephoraceae proved inhibitory to the sapstain isolates Ophiostoma piceae and Sphaeropsis sapinea providing between 94 and 100% control. These isolates were considered for further examination in the field. The remaining isolates provided poor or inconsistent inhibition or were mould fungi and, therefore, not suitable for direct application. All fungal and bacterial isolates that had shown inhibitory ability in the initial biological control screen and the remaining non-staining bacteria were examined for their ability to produce non-volatile metabolites that were inhibitory to sapstain. The bacterial isolates were examined in a preliminary dual plate screen in which 91 isolates were identified as producing inhibitory compounds. The best of these bacterial isolates were screened, with the fungal isolates, in a non-volatile metabolite trial utilising filter sterilised culture filtrates. Isolates of Bacillus sp., Fusarium solani, Gliocladium roseum, Gliocladium virens, Trichoderma harzianum, Trichoderma sp., Trichoderma viride and Trichothecium roseum were found to be significantly inhibitory to the growth of Ophiostoma piceae at concentrations of 50% or less. However, the filtrates did not provide adequate sapstain control, when tested on Pinus radiata wood block, to prompt consideration for further examination in the field. Studies are currently examining several of these isolates for the production of biologically active compounds. The six most promising isolates, from the wood chip and wood block trials, were tested in the field for their ability to control sapstain on unseasoned Pinus radiata sapwood and/or peeled logs. These were Gliocladium viride (FK75), Trichoderma hamantum (FK561), Trichoderma harzianum (FK228), Trichoderma sp. (FK247), Trichothecium roseum (FK238) and an isolate of the Thelephoraceae (FK33). The fungi were prepared as mycelial/spore homogenates. For application to the timber, the homogenates were mixed with 0.2% Alcosorb gel, producing 108 cfu/ml suspensions, these suspensions were applied by dipping. Diluted homogenates, 108 cfu/ml, were applied as spray treatments to the logs. All of the biological control agent treatments reduced the level of sapstain on either the logs or timber with Trichoderma harzianum (FK228), Trichoderma sp. (FK247) and Trichothecium roseum (FK238) providing control equivalent to that of the fungicides NP-1 and Diffusol for portions of the trial. Trichoderma sp. (FK247) and Trichothecium roseum (FK238) gave sapstain control in excess of 90% for the first 30 days of the timber trial equalling the control provided by NP-1 and Diffusol. In another trial, Trichoderma harzianum (FK228) was more effective than NP-1, providing 60% sapstain control, after six months, on the internal tissue of Pinus radiata logs. The six isolates selected for the field trials were examined in additional studies. In a dual inoculation study, Trichoderma sp. (FK247) exhibited localised antibiotic ability causing the lysis of mycelium of sapstain fungi. There was no evidence of mycoparasitic action by any of the six isolates. Trichoderma harzianum (FK228), Trichoderma sp. (FK247) and Trichothecium roseum (FK238) were observed to degrade cellulose. However, neither these nor the other isolates caused a significant change in the mechanical properties of Pinus radiata timber when compared to untreated controls. Decreasing pH or the addition of nitrate were identified as having potential for the promotion of biological control agent growth. The potential of mixed biological control agent inoculations was also examined. While these results are preliminary, they are extremely encouraging and provide a basis from which future studies can develop.

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Bown, Horacio E. "Representing Nutrition of Pinus Radiata in Physiological Hybrid Productivity Models." Thesis, University of Canterbury. School of Forestry, 2007. http://hdl.handle.net/10092/1210.

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Hybrid physiological models are being increasingly used to assess productivity, carbon sequestration, water and nutrient use and environmental impacts of management decisions. Users include forest managers, politicians, environmental agencies and scientists. However a wider use of these models has been prevented as a result of an incomplete understanding of the mechanisms regulating carbon allocation, nutrient availability in soils and nutrient uptake by trees. On-going innovation in clonal forestry, genetic improvement and vegetation management techniques is also poorly represented in hybrid models. This thesis examines means to represent nutrition and genotype-nutrition interactions in productivity physiological hybrid models. Nutrient limitations and growth differences between genotypes were hypothesized to operate through key physiological processes: photosynthesis, carbon allocation and nutrient internal cycling. In order to accomplish the aims of the study both greenhouse and field experimentation were carried out. In a first experiment, responses of photosynthesis (A) to intercellular CO₂ concentration (Ci) were measured in a fast- and a slow-growing clone of Pinus radiata D. Don cultivated in a greenhouse in a factorial combination of nitrogen and phosphorus supply, and analyzed using the biochemical model of leaf photosynthesis described by Farquhar et al. (1980). There were significant positive linear relationships between the parameters, Vcmax, Jmax, Tp and both foliar nitrogen (Na) and phosphorus (Pa) concentration on an area basis. The study showed that the effects of nitrogen and phosphorus supply on photosynthesis were statistically independent and that the photosynthetic behaviour of the two clones was equivalent. In a similar study, gas exchange and chlorophyll fluorescence were simultaneously measured to determine internal transfer conductance (gm) based on the "constant J method". Transfer conductance may pose significant limitations to photosynthesis which may be differentially affected by nutrition and genotype in Pinus radiata. Values of gm were similar to those of stomatal conductance (gs) and their ratio (gm / gs) was not influenced by nutrient supply or clone being on average (±1 SE) 1.22 ±0.04. Relative mesophyll limitations (LM, 16%) to photosynthesis were marginally greater than those imposed by stomata (LS, 13%), and together smaller than the relative limitations posed to photosynthesis by biochemical processes (LB, 71%). The CO₂ concentration in the intercellular air spaces (Ci) was (±1 SE) 53 ±3 µmol mol-1 lower than in the atmosphere (Ca) while CO₂ concentration in the chloroplasts (Cc) was (±1 SE) 48 ±2 µmol mol-1 less than Ci. Values of LS, LM and LB and CO₂ diffusion gradients posed by gs (Ca-Ci) and gm (Ci-Cc) did not change with nutrient supply or clone. In a third experiment, one-year old Pinus radiata cuttings from four genotypes were cultivated in silica sand with a factorial combination of nitrogen (N0=1.43 and N1=7.14 mM) and phosphorus (P0=0.084 and P1=0.420 mM) supply for 24 months. N supply was enriched with ¹⁵N to 2.5⁰/₀₀ (labelled N) during the first year, then plants transferred to clean sand and cultivated for another year with ¹⁵N at levels close to natural abundance (0.3664899 atom percent ¹⁵N, δ¹⁵N 0.5115 ⁰/₀₀) provided by the source of N in nutrient solution applied during the second year. Recovery of labelled and unlabelled N was used to estimate N remobilization. N remobilization scaled with plant growth, N content and N and P supply. In relative terms, 65% of all stored N was remobilized in the high-nutrient supply regime compared to 42-48% at lower N and P addition rates. Most N remobilization occurred during spring-summer (77%), coincidently with the largest proportion of needle development (80%), indicating that N remobilization was driven by sink-strength. Foliage was by far the main source for internal cycling while roots were the main sink (40%). Clones exhibited differences in N remobilization capacity, but these differences were completely explained by the size of the N pool before remobilization took place, indicating that N remobilization performance was similar among clones. In a fourth study, four clones were cultivated in silica sand with a factorial combination of nitrogen and phosphorus supply for ten months, and patterns of carbon allocation examined using a carbon balance approach. Gross-primary productivity (GPP) scaled mainly with nitrogen but also with phosphorus supply. The fraction of GPP (GPP = ANPP + APR + TBCA) allocated to above-ground components (ANPP) increased with N and P supply at the expense of total-below ground C allocation (TBCA) with no apparent effect on the fraction of GPP partitioned to above-ground plant respiration (APR). Carbon use efficiency (NPP:GPP) scaled with nutrient supply, being 0.42 in the low-nutrient supply regime compared to 0.51 in the high-nutrient supply regime, suggesting that in poor fertility environments a larger proportion of the C budget is respired compared to the net productivity. Fast-growing clones allocated about 2-4% more carbon to above-ground components (ANPP) at the expense of carbon allocated below-ground (TBCA) with no effect on carbon respired above-ground (APR), indicating that faster-growing genotypes allocate more carbon to leaf area which may compound and increase overall GPP over time. The field component of this thesis was conducted in a subset of locations where ENSIS (formerly New Zealand Forest Research Institute) had established trials to test the influence of species, soil disturbance and plant nutrition on sustainability indicators. Plots were small in size (3 m × 3 m) with trees spaced at 0.5 m × 0.5 m (40 000 trees ha-1) with nine measurement trees surrounded by a two-row buffer. All sites were planted in winter 2001 and harvested in spring 2005. The aim of this pilot study was to examine patterns of carbon allocation during the fourth year after planting in control and fertilized mini-plots of Pinus radiata in five sites with contrasting climate and soil conditions in the South Island of New Zealand. The study showed that the fraction of gross-primary productivity allocated belowground increased as the soil C:N ratio increased. However, these results should be interpreted with caution due to the unusual nature of the trial and the reduced number of sites studied. Two existing physiological models were selected for the discussion in this thesis (3-PG, Landsberg and Waring 1997; canopy net carbon exchange model, Whitehead et al. 2002). Potential improvements for the nutritional component of 3-PG comprise: accounting for reductions in carbon use efficiency (NPP:GPP) in poor-fertility environments, adding a preliminary fertility modifier (FN, 0-1) driven by soil C : N ratio and soil N, adding a preliminary relationship between carbon allocation to roots and the soil C : N ratio and representing faster-growing genotypes by increasing their leaf area but not their photosynthetic performance. The canopy net carbon exchange model (NCE) combines the coupled model of leaf photosynthesis - stomatal conductance described by Leuning (1995) with canopy structure and a water balance model to scale carbon assimilation from leaves to canopies. Potential improvements to account for nutrient deficiencies in the leaf model by Leuning (1995), comprise using nutrient ratios to discriminate nitrogen (Na/Pa < 23 mol mol-1) from phosphorus deficiencies (Na/Pa > 23 mol mol-1), adding relationships between photosynthetic model parameters Vcmax and Jmax to Pa, and correcting the estimation of photosynthetic parameters Vcmax and Jmax by accounting for transfer conductance (gm). The canopy net carbon exchange model may be also modified to account for carbon-use efficiency, carbon allocation to roots and genotype in a similar form to that proposed for 3-PG. The results previously outlined provide a preliminary framework to represent tree and soil nutrition in physiological hybrid productivity models.

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Midgley, John Claude. "A dendrochronological investigation of Pinus radiata from Silvermine Nature Reserve." Bachelor's thesis, University of Cape Town, 2002. http://hdl.handle.net/11427/26031.

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Whole trunk cross sections of Pinus radiata were collected from Silvermine Nature Reserve, Cape Town. The site was located on a hill in the nature reserve where precipitation was assumed to be a limiting factor in tree growth. Ring widths along 82 radii on 41 samples were measured to the closest 0.1 mm. Samples displaying the highest correlation between ring width values were selected to create a growth index chronology for the site. The resulting chronology was compared to various aspects of precipitation and temperature. Correlation coefficients between tree growth and annual, winter and growth season precipitation levels, minimum and maximum growth season temperatures, mean summer and mean winter temperatures were calculated with the use of a regression analysis. None of the correlation coefficients were above 0.1 , leading to the conclusion that the growth of trees was possibly disturbed by humans while the stand was under Cape Nature Conservation management. An alternative explanation could be that the height at which trees were sampled is likely to cause lowered correlation between samples as proposed by Fletcher (1974b). Although it is not statistically significant, trees displayed similar patterns to precipitation levels since 1955. The conclusion of this study is that Pinus radiata could provide a useful proxy record of climate in South Africa, but an undisturbed site where trees are limited by precipitation needs to be located before attempting the development of another ring index chronology.

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12

Sharma, Rajesh kumar. "Comparison of development of radiata pine (Pinus radiata D. Don) clones in monoclonal and clonal mixture plots." Thesis, University of Canterbury. School of Forestry, 2008. http://hdl.handle.net/10092/1577.

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The development of radiata pine (Pinus radiata D. Don.) clones was compared in monoclonal and clonal mixture plots planted in an experiment established at Dalethorpe, Canterbury, New Zealand with ten radiata pine clones in September 1993. Clones were deployed in a randomised complete block plot design with three replications. Each replication contained ten treatments of monoclonal plots and one in which all the clones were intimately mixed in equal proportions. Clones significantly differed in initial morphologies, survival and stem slenderness. Sturdiness and initial heights were found to be the best predictors of initial survivals. The study revealed that mode of deployment did not affect overall productivity, but individual clones exhibited significantly different productivities between modes of deployment. All clones contributed similarly to overall productivity in the monoclonal mode of deployment, whereas the contribution of clones in the clonal mixture mode of deployment was disproportionate. A minority of the clones contributed a majority of overall productivity in the clonal mixture mode of deployment. The inclusion of competition index as an independent variable in a distance-dependent individual tree diameter increment model explained a significant amount of variability in diameter growth. The use of an inverse-squared distance to neighbouring plants in the competition index provided a slightly superior fit to the data compared to one that employed a simple inverse of distance. Addition of genotype information in the competition index further improved the fit of the model. Clones experienced different levels of competition in monoclonal and clonal mixture modes of deployment. Competition in monoclonal plots remained uniform over time, whereas some clones experienced greater competition in clonal mixture plots which led to greater variability in their tree sizes. This study indicated that single tree plot progeny test selections and early selections may miss out some good genotypes that can grow rapidly if deployed monoclonally. Stand level modelling revealed that clones differed significantly in modeled yield patterns and model asymptotes. Clones formed two distinct groups having significantly different yield models. The study also demonstrated that models developed from an initial few years’ data were biased indicators of their relative future performances. Evaluation of effectiveness of the 3-PG hybrid model using parameter values obtained from destructive sampling and species-specific values from different studies revealed that it is possible to calibrate this model for simulating the productivity of clones, and predictions from this model might inform clonal selections at different sites under differing climatic conditions. Destructive sampling at age 5 years revealed that clones significantly differed in foliage and stem biomass. The differences in productivities of clones were mainly due to differences in biomass partitioning and specific leaf areas. Clones significantly differed in dynamic wood stiffness, stem-slenderness, branch diameter, branch index and branch angle at an initial stocking of 1250 stems/ha. Mode of deployment affected stem slenderness, which is sometimes related to stiffness. Although dynamic stiffness was correlated with stem slenderness and stem slenderness exhibited a significant influence on stiffness, clones did not exhibit statistically significant differences in dynamic stiffness. Increasing initial stocking from 833 stems/ha to 2500 stems/ha resulted in a 56 % decrease in branch diameter and a 17 % increase in branch angle. Trees in the monoclonal mode of deployment exhibited greater uniformity with respect to tree size, stem-slenderness, and competition experienced by clones compared to those in the clonal mixture mode of deployment. Susceptibility of one clone to Woolly aphid suggested that greater risks were associated with large scale deployment of susceptible clones in a monoclonal mode of deployment. This study also indicated that if the plants were to be deployed in a monoclonal mode then block plot selections would have greater potential to enhance productivity.

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Dieste, Andrés. "Colour development in Pinus radiata D. Don. under kiln-drying conditions." Thesis, University of Canterbury. Chemical and Process Engineering, 2002. http://hdl.handle.net/10092/1134.

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This study quantifies discolouration on the surface of Pinus radiata boards during kiln drying, particularly kiln brown stain (KBS), and models it as a function of chemical compounds present in the wood closest to the surface. The discolouration was investigated with two experimental factors: drying time, which consisted in drying at 70/120 ℃ for 0, 8, 16 and 24 hours; and leaching, done at three levels, noleaching, mild and severe, to reduce the soluble compounds present in wood suspected of developing coloured compounds. The colour change was quantified using a reflectance photometer (colour system CIE Yxy, brightness) and by the analysis of digital photographs (colour system CIE Lab). The chemical analysis of the wood closest to the surface of the boards determined fructose, glucose, sucrose (HPLC), total sugar (sum of fructose, glucose and sucrose), total nitrogen (combustion gas analysis), and phenols discriminated by molecular weight (Folin-Ciocalteu method). In the cause-effect analysis, colour was the dependent variable, and drying time and the determinations of chemical compounds were independent variables. After statistical analysis (ANOVA and MANOVA) the dependent variables to be included in the models were luminance factor (Y), brightness (R457 and the blue-to-yellow scale of CIE Lab (b); and the independent variables were drying time, nitrogen, total sugar, and high-molecular-weight phenols. Linear (multivariate regression) and non-linear models (Neural Networks) showed that discolouration during kiln drying was best predicted when the luminance factor (Y) was used to quantify colour change as a function of the content of nitrogen-containing compounds and drying time. Furthermore, the data were fitted into an empirical model based on simple reaction kinetics that considered the rate of discolouration as a function of nitrogen concentration. The results suggest that nitrogen could act as a limiting reactant in Maillard-type reactions that produce colour during kiln drying.

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Denholm, Patricia Margaret. "Biodiversity, biosolids and bioindicators in Pinus radiata D. Don planted forests." Thesis, University of Canterbury. Forestry, 2003. http://hdl.handle.net/10092/6021.

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The global issue of biodiversity was addressed at a local level in this thesis, which examined the effects of a biosolids application programme on the diversity of soil and litter arthropods in Pinus radiata D. Don planted forests in mid Canterbury, New Zealand. A taxonomic inventory of selected sites not only added to the sparse records of entomological data for similar habitats across New Zealand, but also enabled the development of a predictive model for comparison and validation in forward research. Evidence was sought for biosolids-mediated effects in the field on (i) the functional diversity of the arthropod assemblage, (ii) Shannon-Wiener diversity (H') and (iii) an ecologically relevant, invertebrate bioindicator. This novel bioindicator, the larval cranefly Leptotarsus spp. (Diptera:Tipulidae) was further used in a laboratory manipulation in an attempt to quantify the ecological relationship between the genus and soil physical properties. It was then subject to chronic toxicology tests to explore the histological effects of dietary uptake of Cu and Zn. Damage to the gut tissues and a differential effect on the architecture of the fat bodies was shown by histochemistry and light micrography. This evidence providing Support for the "scope for growth" hypothesis, which suggests the allocation of energy to detoxification may impact on an organism's energy reserves, thus affecting growth and development. The larval cranefly Leptotarsus spp. is recommended as a pliable and responsive organism for chronic metal toxicity testing. No support was found for the general hypothesis of a biosolid-mediated effect on arthropod functional diversity at the community level or on the diversity (H') of species. However, there was unequivocal evidence of a significant negative effect on the abundance of the larval cranefly Leptotarsus spp. in the field where dewatered biosolids are applied at rates beyond 400 kg N/ha. It was predicted that cranefly species with a brachypterous female would most likely be affected in forests receiving biosolids applications above 400 kg N/ha. The four cranefly species identified from the study sites were the sale representatives of the myceto/geophagic functional group. Although biosolids applications are likely to constrain both the local diversity and abundance of craneflies, the species redundancy hypothesis predicts ecological processes are unlikely to be affected. Laboratory manipulations failed to show linkage between cranefly larval abundance and their contribution to the generation of porous space in the soil, although these larvae are expected to mediate other soil-related processes, such as the redistribution of fungal inoculants. Arthropod diversity under P. radiata is dominated by generalist species. Greater than 50% of the arthropods trapped were indigenous. The sampled forests clearly provide a refuge within the agricultural mosaic and contribute to the retention of local biodiversity. The trophic structure of the arthropod assemblage was dominated by predatory species. A positive relationship between species diversity (H') and the stage of development of a stand was best described by a logarithmic curve, indicating diversity (H') increased most rapidly during the first (approx.) 10 years of forest establishment. The suites of indicator species identified as significantly indicative of the P. radiata habitat are expected to simplify future assessment at the long-term monitoring sites by offering an investigative tool for the non-specialist. This thesis provides information on the community structure of a highly modified habitat which is of interest to both entomologists and forest managers. As well as giving information on seasonal abundances in relation to trapping methodologies, it provides baseline data and predictive models useful for comparing long-term effects and suggests appropriate bioindicator species as tools for straightforward and cost-effective monitoring in the future. In practice, the main results demonstrated that although biosolids-mediated effects in the Pinus habitat were effectively quantified at the level of genus, forest managers can have a high level of confidence that a significant biosolids-mediated effect on invertebrate biodiversity at the community level is unlikely, at least in the short term, at advised rates of application.

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Zhao, Weizhong. "Growth and yield modelling of Pinus radiata in Canterbury, New Zealand." Thesis, University of Canterbury. Forestry, 1999. http://hdl.handle.net/10092/7148.

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During this study two growth and yield models were developed for Pinus radiata D.Don plantations in Canterbury, New Zealand, namely CanSPBL and CanJuv. CanSPBL is a model for the whole rotation of stands owned by the Selwyn Plantation Board Limited in Canterbury. CantJuv is a model for juvenile growth from after planting to before thinning in Canterbury. An existing stand growth and yield model CANTY was examined using a newly established relational database of PSP measurements. Projection bias was shown for mean top height, basal area per hectare and volume per hectare. Height-diameter relationships were modelled for estimating individual tree height and mean top height. Of the sixteen functional forms evaluated the Petterson equation with exponent -5 and the two-parameter Richards' equation led to the smallest mean square error at stand level. Incorporating stand age, site index and altitude into the selected Petterson equation reduced the mean square error by 72% for a pooled regional data set. The new model, CanSPBL, was achieved with precision at both stand and tree level. The components of the stand model include mean top height, basal area per hectare, stems per hectare, volume per hectare and diameter distribution. The inclusion of altitude into a chosen polymorphic Schumacher difference equation significantly reduced mean square error by 17% for mean top height and 41% for basal area. An examination of this stand model using two sources of data at plot and stand levels showed little apparent bias. Two main model components of tree diameter and tree mortality were developed to complete an individual-tree projection system. For projection of diameter, an approach based on relative basal area was found best, compared with many sigmoid difference equations. A logistic regression procedure showed that relative diameter, altitude, the interaction between initial stocking and projection interval length, and site index were significantly correlated to tree mortality. Nine sets of experimental data and thirty-one temporary plots were used to refine the juvenile growth model of stand level, CanJuv. The components of the model were mean top height, basal area, sectional area at ground level, and survival. Regression analyses identified age, annual rainfall and weeding as the significant factors in determining growth and mortality.

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Rust, Stephanus Marthinus. "Classification of timber from Pinus radiata trees exposed to forest fires." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/98097.

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Thesis (MSc)--Stellenbosch University, 2015.
ENGLISH ABSTRACT: This study aimed to classify wood from trees that were exposed to forest fires with regards to their end use. Exposure to high temperatures over time is known to degrade wood in various ways. This degradation could limit the end use by altering mechanical, chemical and physical properties, leading to difficulty in processing or failing to meet required specifications for various grades. In this study wood from Pinus radiata trees that were exposed to forest fires of different levels of heat intensity was analysed with regards to its anatomical and physical changes. Trees were visually classified into three classes of burn severity. Moisture content measurements were taken from 135 standing trees, divided among the three classes. 30 trees, 10 from each of the three classes, were sampled and used for CT analysis. Samples were taken to include growth from before and after the fire. Two samples were taken from each tree, one from the charred and one from the uncharred side. The CT data was analysed and used to measure properties like growth ring width, cell wall thickness, lumen diameter and cell wall density. The data was used to compare properties from the charred and uncharred sides within a given year, as well as compare properties between years. The study showed that there were significant differences in the MC between the burnt and unburnt sides of trees from classes 2 and 3. The difference between the MC measurements on the burnt sides of three classes differed significantly from each other. Lightness measurements were taken on samples from classes 2 and 3. These samples showed no significant difference between the burnt and unburnt sides for either of the two classes. The samples from the less exposed class were lighter, but not significantly so. The macroscopic wood density was determined using core samples. A decrease in wood density was observed with an increase in fire exposure. The mean densities for all three classes however still fulfilled the requirements for structural timber set by the SABS. Growth ring width, cell wall thickness and lumen diameter analysis gave varied results, with some cases showing a decline in properties while others were seemingly unaffected. For many of the outcomes of this study, results found by previous studies could not be reproduced.
AFRIKAANSE OPSOMMING: Hierdie studie het gepoog om bome wat aan plantasiebrande blootgestel is volgens hul eindgebruik te klassifiseer. Dit is bekend dat blootstelling aan hoë tempreature hout in vele maniere afbreuk. Hierdie afbreuking kan die eindgebruik van die hout beperk deur die meganiese, fisiese en chemiese eienskappe sodanig te verander dat dit kan lei tot probleme met verwerking of ongeskiktheid vir sterktegrade. In hierdie studie is Pinus radiata bome wat aan plantasiebrande van verskillende grade blootgestel is ondersoek in terme van hul fisiese en anatomiese veranderinge. Bome is visueel in drie klasse van verskillende brandskade gegroepeer. Voglesings is op 135 staande bome, verdeel tussen die drie klasse, geneem. Monsters is van 30 bome, 10 uit elke klas, geneem vir CT analiese. Monsters is so geneem dat dit groei van voor en na die brand ingesluit het. Daar is twee monsters van elke boom geneem, een van die gebrande en een van die ongebrande kant. Die CT data is geanalieseer en gebruik om eienskappe soos jaarringwydte, selwanddikte, lumendiameter en selwand digtheid te meet. Die data is gebruik om eienskappe tussen die gebrande en ongebrande kante, sowel as tussen jare te vergelyk. Die studie het gewys dat daar noemenswaardige verskille is tussen die voginhoud van die gebrande en ongebrande kante van bome uit klasse 2 en 3. Die voginhoud van die gebrande kante van al drie klasse verkil ook noemenswaardig van mekaar. Ligtheidmetings is gedoen op monsters van klasse 2 en 3. Die monsters het nie ‘n noemenswaardige verskil tussen die gebrande en ongebrande kante getoon nie. Alhoewel die klas 2 monsters ligter vertoon het as die klas 3 monsters, was die verskil nie betekenisvol nie. Houtdigtheid is bepaal deur fisiese metings op die monsters wat vir die CT skandering gebruik is te doen. ‘n Daling in digtheid met ‘n toename in blootstelling aan die brand het duidelik na vore gekom. Die digtheid is egter nog hoog genoeg om aan die vereistes vir strukturele hout te voldoen, soos die die SABS bepaal. Jaarringwydte, selwanddikte en lumen diameter het wisselende resultate opgelewer, met sommige gevalle wat ‘n afname in eienskappe wys en ander wat ooglopend onveranderd was. Vir vele van hierdie uitkoms kon die resultate van vorige studies nie bevestig word nie.

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17

Fish, Kathryn B. "Biotic resistance to the invasion of Pinus radiata into mountain fynbos." Bachelor's thesis, University of Cape Town, 1989. http://hdl.handle.net/11427/26718.

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Pinjuv, Guy L. "Hybrid forest modelling of Pinus Radiata D. Don in Canterbury, New Zealand." Thesis, University of Canterbury. New Zealand School of Forestry, 2006. http://hdl.handle.net/10092/1102.

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During this study two models were developed to predict growth of Pinus radiata D.Don plantations in Canterbury, New Zealand. The first, CanSPBL(1.2), is a model for whole rotations of stands owned by Selwyn Plantation Limited in Canterbury. The second model, CanSPBL(water) is a hybrid growth model for the Selwyn estate in Canterbury that incorporates an index of root zone water balance over the simulation period. An existing stand growth and yield model CanSPBL was examined using a validation dataset of PSP measurements that were not used in model fitting. Projection bias was shown for mean top height, basal area per hectare, and residual stand stocking particularly for stands at elevations exceeding 450 metres. The new model, CanSPBL(1.2) showed an increase in precision of 4 - 46% over CanSPBL(1.0) at a stand level. The components of the stand model include mean top height, basal area per hectare, stems per hectare, and diameter distribution. The mortality model was made in conjunction with managers at CanSPBL to exclude catastrophic mortality events from model projections. Data used for model fitting was filtered using a mortality index based on the -3/2 power law. An examination of this model with an independent dataset showed little apparent bias. The new model, CanSPBL(water) was developed to include an index of water balance over the simulation period. Water balance estimates were made using a sub model for root zone water balance included in the hybrid physiological model 3-PG (Landsberg and Waring, 1997). The new model showed an increase in precision of 1 - 4% over CanSPBL(1.2) at a stand level (with the exception of the model for maximum diameter which showed a decrease in precision of 0.78%) using climatic inputs that included yearly variation. However the model showed increases of precision from 0.5 to 8% (with the exception of maximum diameter again, showing a decrease in precision of 0.13%) using long term monthly average climatic inputs. The components of the stand model also include mean top height, basal area per hectare, stems per hectare, and diameter distribution. The mortality model was also fitted with a data set filtered using a mortality severity index based on the -3/2 power law to exclude catastrophic mortality events. An examination of this model with an independent dataset showed little apparent bias. Two models to predict a one sided canopy leaf area index (LAI) of radiata pine stands in the Canterbury Plains of New Zealand were also developed. The models were fitted using non-linear least squares regression of LAI estimates against stem measurements and stand characteristics. LAI estimates were derived from digital analysis of fisheye lens photography. The models were kept simple to avoid computational circularity for physiological modelling applications. This study included an objective comparison and validation of a range of model types. The models CANTY (Goulding, 1995), CanSPBL(1.2) (Pinjuv, 2005), CanSPBL-water (Pinjuv, 2005), and 3-PG (Landsberg and Waring, 1997) were compared and validated with the main criteria for comparison being each model s ability to match actual historical measurements of forest growth in an independent data set. Overall, the models CanSPBL(water), and CanSPBL(1.2) performed the best in terms of basal area and mean top height prediction. Both models CanSPBL(water), and CanSPBL(1.2) showed a slightly worse fit in predictions of stocking than did the model CANTY. The hybrid model 3PG showed a better fit for the prediction of basal area than the statistically based model CANTY, but showed a worse fit for the prediction of final stocking than all other models. In terms of distribution of residuals, CanSPBL(1.2) had overall the lowest skewness, kurtosis, and all model parameters tested significant for normality. 3PG performed the worst on average, in terms of the distribution of residuals, and all models tested positively for the normality of residual distribution.

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Guy, Andrew Cleveland. "An Improved Germination Protocol for Pinus radiata, Applicable for Investigation into the Effects of Exogenously Supplied Amino Acids on Seedling Growth, Under Glasshouse and Lab Conditions." Thesis, University of Canterbury. Biological Sciences, 2013. http://hdl.handle.net/10092/8711.

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The two main goals in this research were: (i) to investigate Pinus radiata seed germination methods, identifying areas where improvements could be made and developing a germination protocol applicable for studies under sterile and glasshouse conditions, and (ii) to investigate the potential of L-amino acids as nitrogen fertilisers or growth regulating substances, specifically during early seedling growth of P. radiata. There is a lack of a standard protocol for seed germination of radiata pine. Therefore, a systematic approach was undertaken to develop a germination protocol which was applicable for both commercial and scientific use. It was found that a high percentage of P. radiata seed germination was observed without the need for nutrient-rich plant tissue culture media, stratification, scarification, or elaborate surface sterilisation of the seed. This led to the development of an improved protocol that was simple and relatively inexpensive, resulting in a high percentage of rapid and uniform germination. The main features of this improved germination protocol include: (i) a single-step surface sterilisation with ethanol for 30 seconds, (ii) pre-sowing, imbibition and drying of seeds overnight, and (iii) use of autoclaved moist vermiculite as a germination substrate. L-amino acids are commonly used as organic nitrogen sources for plant nutrition. There is also evidence that exogenously supplied L-amino acids can have effects on plant growth beyond a nitrogen nutrition effect and that these effects are plant species dependent. Since these L-amino acid effects have not previously been investigated in P. radiata, the effects of each of the 20 commonly occurring protein L-amino acids on radiata pine growth were investigated. Five L-amino acids (Arginine, Aspartic acid, Proline, Lysine and Serine) were identified as having nitrogen nutrition independent effects. Under laboratory conditions these effects were determined to be concentration dependent and could therefore be of physiological significance. Under glasshouse conditions, the L-amino acid effects were subject to the influences of soil factors. The L-amino acid effects identified in this research can be considered novel and warrant further investigation.

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McQuillan, Shane. "Above and Below Ground Assessment of Pinus radiate." Thesis, University of Canterbury. School of Forestry, 2013. http://hdl.handle.net/10092/9897.

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A comparison of above ground forest metrics with below ground soil CO₂ respiration was carried out in an attempt to reveal if any correlations exist. Above ground measurements of 2720 clonally propagated trees were taken assessing the silvicultural treatments of stocking, herbicide and fertiliser. These were compared to 480 below ground soil CO₂ respiration measurements. Using measurements of mean height, mean dbh and basal area the data was analysed and returned significant results for mean dbh and the interactions of herbicide and clones, and stocking and herbicide. Mean height returned a significant result for the interaction of stocking and herbicide. Below ground measurements showed an interaction between ripping and stocking; however these results were not ratified by the above ground results. Overall the results were encouraging and should aid in future experiments that seek to understand what effect above ground treatments have on below ground CO₂ activity.

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Barrios, Rodríguez Andrés. "Determinación del diámetro del cilindro defectuoso en trozas podadasde pino radiata (Pinus radiata D.Don), mediante atenuación de radiación gamma." Tesis, Universidad de Chile, 2004. http://www.repositorio.uchile.cl/handle/2250/105025.

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Nair, Hema. "A study of intra-ring checking and xylogenesis in Pinus radiata D.Don." Thesis, University of Canterbury. Biological Sciences, 2006. http://hdl.handle.net/10092/1325.

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Pinus radiata is the dominant species of the plantations forests in New Zealand. The forest industry in New Zealand is heavily dependant on it. However, Pinus radiata can develop wood quality flaw called 'intra-ring checking'. The checks or splits appear in wood during kiln drying and usually affect the earlywood region of the wood. It lowers value of appearance grade timber leading to huge economic loses for the forest industry. This thesis presents a study that was undertaken as a part of ongoing collaborative work that is being carried out to understand wood quality issues in Pinus radiata, with a vision of improving its wood quality. This study was a part of that effort and was conducted with an aim to gain an insight into intra-ring checking, and the process of xylogenesis in Pinus radiata. The investigations for this study were carried out in two steps. The first step was to understand intra-ring checking. The location of intra-ring checking was determined by observing the checks using various microscopy techniques. Scanning electron microscopy confirmed that checking was as an intercell failure that usually occurs at the cm1/S1 boundary. A comparative study was also conducted to see if the checked wood had some inherent properties that made it more susceptible to checking. It was found that checking could be influenced by tracheid geometry and cell wall thickness. If the wood had large tracheids with thin walls, it was more likely to develop checks during drying. Lignin distribution in the cell wall layers was also seen to play an important role in checking. Lower lignin levels and disruption in the pattern of lignification of the cell wall layers increased the tendency of the wood to develop checks. Similarly, it the tracheids have larger pits then their tendency to check increases. Structural features that disrupt the uniformity of the interlocking pattern of the tracheid such as rays and resin canals could also play a role in checking. Checked wood tends to have more surface area occupied by ray tissue. However, resin canals do not seem to be directly involved in checking, though their arrangement could indicate disturbances during xylogenesis. The second step was to understand the process of xylogenesis in Pinus radiata especially with respect to the influence of auxin and boron on it. Nutrient and organ culture methods were manipulated and successfully used to study xylogenesis. An exhaustive comparative study was carried out to observe and measure selected wood properties. Microscopy and image analysis revealed that auxin and boron changes in the medium led to the alterations in the cell division, expansion and lignification. However, the analysis of the measurements and the observations displayed complex 'between-tree' and 'within-culture variations'. Clear trends did not emerge from the analysis hence, a confident conclusion on the association between auxin, boron and lignification could not be drawn from this organ culture study. The study has added to the knowledge about checking and wood properties associated with it. A new tool of organ culture had been established that can hlep future research on the process of xylogenesis in Pinus radiata.

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23

Clinton, Peter William. "Competition for nitrogen and moisture in a Pinus radiata-pasture agroforestry system." Thesis, University of Canterbury. Forestry, 1990. http://hdl.handle.net/10092/6755.

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A 3 x 2 factorial experiment was conducted to examine the outcome and some of the competitive mechanisms between P. radiata (D. Don) and pasture for N and soil moisture. The factors examined were the monthly addition of 30 kg N/ha versus no additional N, and the manipulation of the level of pasture competition by spraying and simulated-grazing to give three levels of pasture competition. The experiment coincided with a period of severe drought which greatly increased the competition for soil moisture. Removal of pasture competition by spraying released a large amount of N into the soil mineral N pool. It also reduced overall demand for N and water because of the reduction in competition resulting in improved tree growth and greater N uptake by trees. However, it was apparent that moisture was the main limiting factor for tree growth in the plus-pasture treatments because, whilst trees did take up some of the applied N in the plus-pasture treatments, they showed no increase in growth and N uptake. A localized effect of trees on pasture dry matter production and N content occurred. Directly beneath trees and in the area predominantly occupied by tree roots competition for water and N was intense. Pasture response to N was greatest away from the tree rooting zone. Pasture appeared to compete successfully due to the nature of its root system which consists of a large biomass of very fine roots compared to the small biomass of fine pine roots in the surface soil. Competition between pasture and trees was further examined using the stable isotope 15N to trace a single 15N-labelled application of N fertilizer in spring. Recovery of 15N during the split fertilizer application program was assessed by periodic pasture harvests in the simulated-grazing treatment and by obtaining a complete balance sheet after 249 days. The dynamics of plant availability of applied 15N and retention of 15N in the soil was also followed. The recovery and retention of 15NO3- and 15NH4+ in particular were compared in the simulated-grazing treatment. Larger quantities of 15NO3- remained available to plants than 15NH4+ and 15N was still found in the KCl-extractable mineral N pool at 154 and 249 days after application. P. Radiate assimilated the same amount of 15N when added as 15NO3- or 15NH4+ in the simulated-grazing treatment but uptake into the aboveground biomass of pasture was greater for 15NO3- than for 15NH4+. However, pasture uptake of 15NO3- and 15NH4+ was not significantly different when pasture stubble and roots were include in the total recovery for all harvests. Removal of pasture competition increased the availability of 15N for the period just after application but 15N uptake by P. radiata was only doubled. There were no significant differences in 15N recovery between treatments in the 0-20 cm depth of soil; on average this was 49% of that applied. Total system recovery was 107, 92, 76, and 71% for the 15NO3-treated, 15NH4+ -treated simulated-grazing treatments, 15NH4+ -treated rank, and sprayed treatments, respectively. The loss of 15N from the system was not accounted for by leaching although this was not directly measured. In the sprayed treatment where the loss of 15N was greatest, it was thought that 15N loss may have been due to denitrification. The root systems of neighbouring trees did not overlap and midway between the trees there was apparently no competition between trees and pasture since no effect of tree roots on pasture growth and 15N uptake could be shown. Uptake by artificially-grazed pasture did not seem to reduce 15N movement into the canopy to the same extent as uptake by rank pasture. In the simulated-grazing treatment the increased cycling of N or reduced pasture root growth may have provided some benefit to tree uptake of 15N.

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24

Li, Mingshan. "Studies on adventitious root formation in Pinus radiata : biochemical and molecular aspects." Thesis, University of Canterbury. Plant and Microbial Sciences, 2000. http://hdl.handle.net/10092/5842.

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A reliable in vitro rooting system was established for further studies on biochemical and molecular aspects during adventitious root formation in Pinus radiata hypocotyls. High root counts and rooting efficiency were observed in a medium comprising ½ strength of the Murashige & Skoog's basal medium (1962), 20 g/l sucrose, 9 mg/l IBA and solidified with 8 g/l agar. In this system, the first cell division, formation of root primordium initial (a cluster of meristematic cells), well-organized root primordium (a dome shaped structure) and root emergence were typically observed at around day 4, 7, 10 and 13, respectively. The increase of buffer soluble total proteins resulted in a peak at day 7 in the treatment with IBA (rooting treatment), but this peak was not observed in the other non-rooting treatments (including IBA+kinetin, kinetin alone and hormone-free control). Rooting related proteins were not observed using one-dimensional SDS polyacrylamide gel electrophoresis (PAGE). However, 19 proteins associated with the IBA treatment were observed by two-dimensional PAGE although their magnitudes were very small so that it was difficult to quantify them and establish them as novel proteins. Changes of peroxidase (PO), IAA-oxidase (IAA-O), amylase (Amy) and succinic dehydrogenase (SDH) activities assayed using tissue extracts were not significantly different between the rooting and the non-rooting treatments during the experiment. By contrast, the increase of polyphenol oxidase (PPO) activity was more significant at day 7 in the rooting treatment than in the other treatments. Nevertheless, histochemical localization of PO, PPO and SDH indicated that these enzymes were somehow associated with adventitious root formation. In the IBA treatment, the increase of starch content in the rooting region reached its maximum at day 4 and 7. This increase coincided with the histological observation ofaccumulation of starch grains at the sites where root primordia initiated. To identify the molecular signals that initiate adventitious root formation, subtracted cDNA library was made from IBA-treated hypocotyls following polymerase chain reaction (PCR) amplification of subtracted single strand-cDNAs. Inserts of 5 bacterial clones (Rl-72, R2-7, R2-22, R2-35 and R3-24) were digoxigenin-labelled and used to detect their corresponding transcripts using RNA dot blotting. Using RNA dot blotting analysis, Rl-72 detected an equivalent level of transcript in the hypocotyls at day 0 and day 7 in the treatments with and without IBA; whereas the other 4 clones, especially R2-7 and R2-35, detected different levels of transcripts in the hypocotyls during adventitious root initiation. Southern blotting analysis indicated that the R2-7 transcript is likely to be represented by a single gene or a member of a smaller gene family. Adventitious root formation in P. radiata was significantly improved using Agrobacterium rhizogenes. Compared with the strain A4T, strain LBA9402 was very effective in increasing rooting percentage and root number. High rooting percentages and root numbers were obtained in the trials with hypocotyl segments, intact seedlings and adventitious shoots. The findings in this research can assist further studies to shed some light on why some clonal cuttings of radiata pine root more easily than others do, and why mature cuttings are difficult for adventitious root induction.

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25

Dale, Tracy Maree. "A study of T-DNA integration and transgene expression in Pinus radiata." Thesis, University of Canterbury. Biological Sciences, 2004. http://hdl.handle.net/10092/7223.

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Pinus radiata D Don. is the key resource for the New Zealand forest industry. Genetic engineering could potentially accelerate its genetic improvement by the introduction of novel traits or modification of existing traits, with both environmental and economical importance for the industry. In this study PCR and Southern hybridisation confirmed stable T-DNA integration in P.radiata plants produced by Agrobacterium-mediated gene transfer. Southern analysis showed a predominance of single T-DNA integration events. However, incomplete transfer leading to truncated copies of the T-DNA appeared to be common. TAIL-PCR was used to identify TDNA/ genomic DNA junctions in five transgenic P.radiata lines. Sequence analysis of these junctions showed attachment of residual vector DNA at the right border for all five lines. We suggest this may reflect the recalcitrance of P.radiata to Agrobacterium infection. Rearrangement of the integrated T-DNA was analysed in detail for two transgenic P.radiata lines and revealed features common to both lines including deletion of T-DNA sequence, presence of plant genomic DNA within the T-DNA loci, and T-DNA rearrangement around the CaMV 355 promoter region. The visual marker genes β-glucuronidase (uidA) and green fluorescent protein (gfp) were evaluated for their potential use in regenerated P.radiata tissue. Detection of uidA by histochemical staining was poor and unpredictable. Factors within the plant cell appeared to either inhibit the B-glucuronidase enzyme or interfere with the chemistry of the histochemical reaction. GFP could be visualised using epi-fluorescence microscopy in all cell types of needles removed from transgenic P.radiata plants, and could be distinguished from background autofluorescence. An image analysis system was used to compare GFP expression between lines. Transgenic lines with high levels of GFP expression were distinguished from transgenic lines with low levesl of GFP expression. Comparison of GFP expression between clonal shoots propagated from single transgenic P.radiata lines showed that the lines analysed were not chimeric in origin. Understanding the predominant characteristics of Agrobacterium-mediated T-DNA integration in P.radiata plants in conjunction with an efficient visual marker-gene system to evaluate transgene expression will improve transformation strategies and thus the stable expression of transgenes.

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26

Gorman, Susan Wilkie. "Initial characterization of the 5S and ribosomal gene families in Pinus radiata." Case Western Reserve University School of Graduate Studies / OhioLINK, 1992. http://rave.ohiolink.edu/etdc/view?acc_num=case1059655407.

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27

Welsh, Shayne. "Hormonal control of wood formation in radiata pine." Thesis, University of Canterbury. Biological Sciences, 2006. http://hdl.handle.net/10092/968.

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Pinus radiata is by far the dominant species grown in New Zealand plantations as a renewable source of wood. Several wood quality issues have been identified in the material produced, including the high incidence of compression wood, which is undesirable for end users. At present our understanding of the complex array of developmental processes involved in wood formation (which has a direct bearing on wood quality) is limited. Hence, the forest industry is interested in attaining a better understanding of the processes involved. Towards this goal, and for reasons of biological curiosity, the experiments described in this thesis were carried out to investigate several aspects of xylem cell development. In an in arbor study, changes in the orientation of cortical microtubules and cellulose microfibrils were observed in developing tracheids. Results obtained provide evidence that cortical microtubules act to guide cellulose synthase complexes during secondary wall formation in tracheids. The mechanisms involved in controlling cell wall deposition in wood cells are poorly understood, and are difficult to study, especially in arbor. A major part of this thesis involved the development of an in vitro method for culturing radiata pine wood in which hormone levels, nutrients, sugars and other factors, could be controlled without confounding influences from other parts of the tree. The method developed was used in subsequent parts of this thesis to study compression wood development, and the influence of the hormone gibberellin on cellulose microfibril organisation in the cell wall. Results from the in vitro compression wood experiments suggested that: 1. when a tree is growing at a lean, the developing cell wall was able to perceive compressive forces generated by the weight of the rest of the tree, rather than perceive the lean per se. 2. ethylene, rather than auxin, was involved in the induction of compression wood. Culture of stem explants with gibberellin resulted in wider cells, with steeper cortical microtubules, and correspondingly steeper cellulose microfibrils in the S2 layer of developing wood cells. This observation provides further evidence that the orientation of microtubules guides the orientation of cellulose microfibrils. Overall, the work described in this thesis furthers our knowledge in the field of xylem cell development. The stem culture protocol developed will undoubtedly provide a valuable tool for future studies to be carried out.

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28

Wang, Eric Yunxin. "Properties and Distortion of Douglas-fir with Comparison to Radiata Pine." Thesis, University of Canterbury. Chemical and Process Engineering, 2009. http://hdl.handle.net/10092/3556.

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The objectives of this study were to investigate stability related basic wood properties and to determine stability performance of New Zealand grown Douglas-fir and those of radiata pine wood. In this study, nine 60-year old Douglas-fir trees and thirteen 26-year old radiata pine trees were selected from forests in Canterbury region. From these trees, 36 discs of 200 mm thick (13 for Douglas-fir and 23 for radiata pine) and 388 boards with dimensions of 100mm x 50mm x 4.8m (210 fro Douglas-fir and 178 fr radiata pine) were prepared. From the prepared discs, 515 specimens (204 for Douglas-fi and 211 for radiata pine) were prepared for green moisture content (MC) and basic density measurements, The same total number of 515 specimens (205 for Douglas-fir and 210 for radiata pine) were also prepared for shrinkage measurements. From the green MC specimens, green weight, volume and oven-dry weight were measured while for the shrinkage specimens, dimensions and weights were measured at equilibrium for nine humidity conditions. These data were used to analyse basic wood properties and moisture uptake characteristics for both Douglas-fir and radiata pine. Variation of shrinkage within a tree and between trees was also studied for both species. After this, selected specimens (36 for Doulas-fir and 36 for radiata pine) were further tested in water immersion for water repellence examination. The 388 full size boards (100mmx50mmx4.8m) were used for studies on distortion and acoustic properties at a sawmill (Southland Timber Ltd.). Dimensions, weights and acoustic velocity were measured from each board before and after drying. These data were used to analyse distortion and strength characteristics for both Douglas-fir and radiata pine. Comparison of the relative stability of full sized Douglas-fir and radiata pine structural timber was investigated in this study. The results from small sample study confirmed that Douglas-fir is much stronger, has lower longitudinal shrinkage and lower gradient in corewood which can be used to explain the better dimensional stability of Douglas-fir than radiate pine although there is significant variability in the shrinkage for both Douglas-fir and radiate pine. In water immersion tests, Douglas-fir has better water repellency property than radiata pine over 2000 hours period during water immersion. Under the same commercial practice in sawing and kiln drying, it is clearly shown that Douglas-fir timbers were straighter with lower levels of distortion than radiata pine at similar final moisture content. It is also interesting to note that the final moisture content in a range of 13-18% for Douglas-fir did not have significant impact on timber distortion but a negative trend was observed for radiata pine with MC in a range of 9 -14%. Tree heights showed clear influence on twist for radiata pine timbers, but it was not clearly observed from Douglas-fir timbers. Corewood proportion is found to have negative impact on the timber distortion for both Douglas-fir and radiata pine. Douglas-fir timbers showed much higher average acoustic MOE value than radiata pine timbers at similar final moisture content. Because of the various proportion of corewood, the shrinkage varied greatly along the stem height and along the disc radius direction for the two species. This variation caused the difference of distortion between corewood, outerwood and transition wood, but the difference between butt log, middle log and top log is inconsistent. Therefore, it is recommended that the corewood proportion to be a criterion for the timber pre-sorting. Variation of stability performance between trees was also found to be significant for the two species, and methods need to be developed for log sorting as well to reduce the timber distortion degradation. Non-destructive testing method such as acoustic tool may be offered to be a new approach for sorting logs, but it is also necessary to be aware of the significant difference between species. The outcome from this project includes better understanding of Douglas-fir for structural applications. The conclusion can be drawn that Douglas-fir has superior quality for its strength, durability and moisture resistance. Douglas-fir is also claimed to have uniform properties and thus to be more stable compared to radiata pine. Douglas-fir timbers showed much higher acoustic MOE value than radiate pine timbers as similar final moisture content.

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29

Thomas, Jimmy. "An investigation on the formation and occurrence of spiral grain and compression wood in radiata pine (Pinus radiata D. Don.)." Thesis, University of Canterbury. Biological Sciences, 2014. http://hdl.handle.net/10092/9654.

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Radiata pine (Pinus radiata) is the most important plantation tree in New Zealand forestry, and factors that reduce the quality of wood cause significant economic loss. Two of the most important of these issues are compression wood and spiral grain. Compression wood is a type of reaction wood, formed when a tree moves away from the vertical, and is characterised by biochemical and structural changes within the wood that reduce its quality and value. Spiral grain, however, is the alignment of the wood grain in a helix around the tree’s axis and away from the vertical. Again, this reduces the structural qualities of the wood and thus its value. Spiral grain and compression wood are notorious for their deleterious effect on the quality of wood produced and are very important for the forest industry due to the huge economic loss they cause. The demand for reliable tools to evaluate these wood quality issues in clonal planting material at an early stage, within 3 years of germination rather than at 8 to 15 years as in current practise, is of ever increasing importance from plant breeders and other industry stake holders. Therefore this research was undertaken with an overall aim to develop quick, easy and reproducible techniques to evaluate young radiata pine clones (up to 3 years old) based on compression wood content and presence of spiral grain. This is important because a shortened breeding cycle could provide significant economic benefits to the forest industry. The incidence of these commercially important wood quality parameters has been studied in this thesis in research conducted on young trees (1 to 3 years old). The research described in this thesis used a variety of different imaging approaches to investigate wood structure, including polarised light and confocal microscopy, and X-ray tomography and circular polarised light scanning. The images achieved have been analysed using a range of different software, including Photoshop, ImageJ and Matlab bringing a quantification approach to the imaging. Compression wood was quantified in young clonal material using images collected with a commercial document scanner, and processed using image analysis tools available in Photoshop. An easy, reliable and robust, automatic image analysis protocol was successfully developed and tested for the detection and quantification of compression wood in these young trees. This new technique to detect and quantify compression wood was based on the thresholding of the blue channel of the scanned RGB image as this was demonstrated to contain the greatest image contrast. Development of this new technique may reduce the waiting time for screening clonal planting materials based on compression wood content. To understand the organisation of the grain at a cellular level within these young trees, confocal microscopy techniques were utilised. The cell wall characteristics and fluorescence properties of compression wood in comparison with normal wood were investigated using a new cellulose specific dye, pontamine fast scarlet 4B. Staining protocols for this dye for confocal microscopy were optimised, and the potential of measuring the microfibril angle of the S1 and S3 layers of the pontamine treated opposite wood was demonstrated through either direct observations of these layers, or through the property of bifluorescence where the dye is excited only when aligned parallel to the polarisation of the incident light. Despite extensive work with confocal microscopy, this technique proved to be unsuitable for investigations of spiral grain because although it provided cellular detail, imaging was limited to the surface layers of sections, and the area over which observations were required was prohibitive. Instead of confocal microscopy, the incidence of spiral grain in young stems was investigated in two completely new ways. Resin canals, which are formed from the same cambial initials as the tracheids and which align with the grain, were used as a proxy to demonstrate the grain changes. A novel technique, using circular polarised light and a professional flatbed scanner, was developed to image whole serial transverse sections of the young stems to detect the resin canals. Using ImageJ, the number and location of resin canals was measured on vertical controls, and trees that had been rocked and leaned. The number and frequency of resin canals were less in tilted trees, especially in compression wood, compared to the higher number of canals formed in the rocked trees. More importantly, a combination of serial sectioning and this approach allowed a 3-dimensional view of the orientation of resin canals inside a stem to be generated with ImageJ, and the angles of these canals could be measured using Matlab. The resin canals were oriented with a left-handed spiralling near the stem surface whereas the canals near to the pith were nearly straight, consistent with previous observations of the development of spiral grain in radiata pine. However, it was observed that while vertical trees had a symmetric pattern of grain and grain changes around the stem, this was not the case in tilted trees. In these, the opposite wood often had severe spiral grain visible through formation of twist whereas the compression wood formed on the lower side had bending. Consistent with this, grain associated with compression wood was significantly straighter than in opposite wood. This hitherto unknown link between the incidence of compression wood and spiral grain was investigated and explained on the basis of the characteristics of resin canals in these types of wood. X-ray micro-tomography was also used to investigate resin canals in the stubs from which serial sections were collected. The 3D reconstructions of the resin canals showed exactly the same patterns as observed by polarised light scanning.

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30

Pongracic, Silvia School of Biological Sciences UNSW. "Influence of Irrigation and Fertilization on the Belowground Carbon Allocation in a Pine Plantation." Awarded by:University of New South Wales. School of Biological Sciences, 2001. http://handle.unsw.edu.au/1959.4/18164.

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The aboveground and belowground productivity of forest systems are interlinked through complex feedback loops involving tree, soil and environmental factors. With a predicted significant change in environmental conditions through the enhanced greenhouse effect, it is important to understand the response of forest systems to these new conditions. An increase in atmospheric CO2 is predicted to increase photosynthesis, and therefore whole plant productivity at the individual tree level. However this increase in photosynthesis may result in greater requirements for nutrients, particularly nitrogen (N). In order to acquire any additional available N, trees may respond by increasing their proportional allocation of C belowground to the root system. This study aimed to quantify the belowground C allocation in a mature forest system consisting of a single species on a single site, but with different levels of water and nutrient stress. The belowground carbon dynamics of a range of irrigated and fertilized Pinus radiata stands in Australia were investigated during 1992 and 1993. Belowground carbon allocation was estimated using the model proposed by Raich and Nadelhoffer (1989) where belowground C allocation is the difference between soil respiration and carbon input through litterfall, plus coarse root production and an adjustment for any change in soil and litter layer carbon pools. This model is best described by the equation: Belowground C = Csoilresp ?? Clitterfall + Ccoarseroot+ ???Cforest floor+ ???Csoil Soil respiration, measured using a modified soda lime absorption method either every 2 weeks or every 4 weeks for 2 years, showed a range in daily soil C flux from 137 ?? 785 mgCO2.m-2.h-1. Soil respiration showed seasonal trends with summer highs and winter lows. Limited fine root biomass data could not indicate a strong relationship between measured soil respiration and fine root (>2mm diameter) biomass. Fifty three percent of the variation in soil respiration measurements in irrigated treatments was explained by a linear relationship between soil respiration, and soil temperature at 0.10 m depth and litter moisture content. In non-irrigated treatments, 61% of the variation in soil xix respiration measurements was explained by a linear relationship between soil temperature at 1 cm depth and soil moisture content. Inter-year variation was considerable with annual soil respiration approximately 20% lower in 1993 compared with 1992. Annual soil C flux was calculated by linear interpolation and ranged from 3.4 ?? 11.2 tC ha-1 across the treatments. Soil C pools remained unchanged over 10 years between 1983 and 1993 for all combinations of irrigated and fertilized stands, despite significant aboveground productivity differences over the decade. Measurements of standing litter showed a change between 1991 and 1993 for only 2 out of the 10 treatments. These two treatments had belowground C allocation estimated both with and without an adjustment for a change in standing litter. Annual litterfall C ranged almost four fold from 0.6 ?? 2.2 tC ha-1 between the treatments in 1992 and 1993, and fell within the ranges of measured litterfall over 10 years at the field site. Again inter-year variation was large, with the 1993 litterfall values being approximately 97% greater across all treatments compared with 1992 values. Belowground carbon allocation was calculated using C fluxes measured at the field site, and ranged 3 fold from 4.4 ?????? 12.9 tC ha-1 between the treatments during 1992 and 1993. In 1993 the belowground C allocation was approximately 30% lower across all treatments compared with 1992 calculations. This was due to an approximate 23% reduction in annual soil C flux, a 97% increase in litterfall C and an 18% reduction in coarse root production between 1992 and 1993. The field site was N limited, and differences in belowground C allocation could be shown across irrigated treatments with different N limitations. As N availability increased belowground C allocation was decreased in the irrigated treatments. It was difficult to determine differences in belowground C allocation caused by water stress as the effects of water and N limitation were confounded. An increase in N availability generally indicated an increase in coarse root and litterfall C production, which were reflected in increased aboveground productivity. In high N treatments the coarse root fraction of belowground C allocation comprised approximately 50% of the total belowground C allocation, whereas in the N stressed treatments coarse roots only comprised 20% of the total belowground allocation The mechanistic model BIOMASS was used to estimate annual gross primary productivity (GPP) for the different treatments at the field site. BIOMASS estimated GPPs of between 30-38 tC ha-1 for the different treatments during 1992 and 1993. The measured belowground carbon allocation ranged from 16 ?? 40 % of simulated GPP, with the lower proportion allocated belowground in the irrigated and high fertility stands. Aboveground competition through the absence of thinning also appeared to reduce allocation belowground in non- irrigated stands. A direct trade off between bole and belowground C could not be demonstrated, unless data were separated by year and by the presence or absence of irrigation. Where data were separated in this manner, only three data points defined the reasonably strong, negative relationship between bole and belowground C. The value of this relationship is highly questionable and should be interpreted with caution. Thus a decrease in belowground C allocation may not necessarily indicate a concomitant increase in bole C allocation. Inter-year variation in a number of C pools and fluxes measured at the field site was at least as great as the variation between stands having different water and N limitation. Extrapolation of belowground productivity estimates from a single years data should be undertaken cautiously. The work undertaken in this study indicated that for a given forest stand in a given soil type, an increase in N availability reduced the absolute and relative C allocated belowground. However this decrease in C belowground may not directly translate as an increase in stem growth or increased timber production. Forest productivity in an enhanced greenhouse environment is likely to result in an increased allocation of C belowground due to increased N limitation, unless adequate N is present to support a more active canopy. Further work is required to more fully understand the dynamics of the belowground system in a changing environment. However further research should focus on mature forest systems in order to isolate the impacts of natural ageing changes from perturbation effects on the forest system. This would be best undertaken in long term monitoring sites where a C history of the stand may be available.

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31

Williams, Moira Caroline. "The ecological impacts of invasive Pinus radiata in eucalypt vegetation: pattern and process." School of Biological Sciences. University of Sydney, 2008. http://hdl.handle.net/2123/2761.

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Doctor of Philosophy (PhD)
Early recognition of plant invaders is key to their successful management. Yet knowledge of the ecological impacts of species before they become widespread is poor. This thesis examines the ecology of invasive Pinus radiata, a species which is known to spread from introduced plantings in Australia but is currently a low profile invader. Pinus invasions are considered major ecological problems in New Zealand and South Africa where wildlings are beginning to dominate natural areas and suppress native vegetation. Invasion success elsewhere and the large softwood estate in Australia suggest that pines may begin to dominate native eucalypt forests bordering large commercial plantations. This research focused on three components of impact of P. radiata; extent, abundance and effect per individual. The borders of 29 P. radiata plantations in NSW were surveyed in order to quantify the current level of invasion and to identify factors facilitating pine spread. Of particular interest was the role of propagule pressure, vegetation type and fire in the invasion process. The area of land in NSW currently invaded by P. radiata was estimated at almost 4 500 ha, although this is likely to be an underestimate due to an inability to detect wildlings (self-sown pines) at long distances from the plantation. Twenty six of the 29 plantations produced wild pines, however most of the sites are in the very early stages of invasion. Noticeable wildling populations were recorded at nine sites indicating that P. radiata is capable of establishing within native vegetation. Pine spread was most severe in the world heritage listed Blue Mountains region where pine densities reached up to 2000 per hectare in areas adjacent to the plantation and isolated pines were recorded up to 4 km from the source. The presence of isolated pines within intact native vegetation suggests that disturbance is not required for pine establishment in forested environments. Furthermore, high pine emergence and survival rates in eucalypt woodland and evidence of self reproduction by wildlings suggest that in the absence of adequate control measures pines may become established invaders in the Australian landscape. While low levels of current invasion at many sites hindered the ability to examine the factors facilitating invasion some variables that appear to be driving pine success were identified. At the landscape scale plantation size and residence time were significant predictors of the level of invasion at a site. Areas of native vegetation vi adjacent to plantations less than 40 years experienced very low levels of invasion suggesting a lag period between plantation establishment and invasion. However, pines with diameters up to 60 cm were observed growing adjacent to plantations younger than 40 years implying that the first colonisers are capable of establishing soon after plantation trees become reproductive. Propagule pressure was also found to have a strong influence on invasion success on a smaller scale manifesting in a significant positive relationship between the age of a plantation compartment and the likelihood of invasion. A negative relationship between plantation size and level of invasion was a surprising result and was influenced by just two large sites that happened to be located in areas of high rainfall. All sites receiving more than 1300 mm annual rainfall experienced low levels of invasion suggesting that this is a limiting factor for pine spread in NSW. There were significant differences in the level of invasion between vegetation types implying that some communities are more susceptible to invasion. Patterns of spread confirmed ideas regarding the facilitative effect of disturbance in the invasion process and the resistance of wet sclerophyll forest to invasion in Australia. An absence of wildlings in cleared land and areas of remnant bushland was attributed to high levels of grazing pressure. Wind direction did not appear to influence the distribution of pines close to the plantation, but evidence of long distance wind dispersal of pines was provided by an investigation of pine spread from the air at one site where large pines were found growing 10 km downwind from a mature plantation. Fire was found to have both a positive and negative influence on the invasion process. High intensity wildfires are capable of destroying large pines with diameters exceeding 50 cm. However, fire can stimulate seed release from cones resulting in large post-fire recruitment pulses. Seedling densities of up to 3050 per hectare were recorded almost 3 years after wildfire, suggesting that follow up control prior to recruits reaching coning age, i.e. within 5 years, would be beneficial. Surveys of wildling pines exposed to low intensity hazard reduction burns suggest that the majority of pines greater than 3 m in height and with a diameter of more than 10 cm will survive the fire. Low intensity prescribed fires that are carried out after pines have reached this size will fail to control wildling populations. To examine the influence of P. radiata once it has established in the native community this study focused on two mechanisms of impact, the addition of pine litter and increased shade due to an increase in canopy cover. Collection of pine litterfall vii within an invaded eucalypt woodland over a 2 year period recorded rates of up to 1400 kg/ha/year in the most heavily invaded area with a pine basal area of 11.3m2/ha. More than 70 % of pine litter fell directly below the pine canopy suggesting that the most severe litter effects will be limited to these areas. Glasshouse and field experiments were conducted to examine the influence of this increased litter load on the emergence of P. radiata and two native species. Recruitment of native plant species was impeded by litter levels of 6000 kg/ha, the equivalent of approximately 4 years of pine litterfall. Both P. radiata and the two natives responded similarly to pine and eucalypt litter suggesting the two litter types are influencing the recruitment phase equally. However, where pines are added to the system, increased litterfall rates could potentially result in the doubling of the litter load and hence a greater barrier to seedling establishment. Pine invaded eucalypt woodlands are also subjected to three fold increases in canopy cover. Trends in reduced emergence of native species under a pine canopy suggest that the addition of pines to eucalypt forests is likely to have a negative influence on native recruitment and may result in a shift towards a shade tolerant community. However, reversal of trends in emergence below pine canopy between seasons implies that quantifying invasion impacts requires a consideration of temporal variation. Increased levels of disturbance, forest fragmentation and an increasing pine estate are likely to lead to the infestation of new areas. Furthermore the lag phase associated with pine spread means that even if no new plantations are established the number of invasion events will increase. This study has identified a number of risk factors that can be used to guide plantation establishment and the management of invasion events. Minimising disturbance at plantation borders and increasing the ‘no planting’ zone will help to reduce the impacts of pines. Where possible new plantations should be established upwind of cleared land or at least, wet sclerophyll forest. Frequent monitoring of the borders of plantations yet to source invasions, particularly those greater than 40 years of age, will help identify problem areas before control becomes difficult and costly. Maps of the 29 plantations marked with areas of pine infestation will help prioritise sites for control and provide base level knowledge for future monitoring of pine spread. Stringent legislation that binds plantation managers to control wildlings beyond their boundaries is critical for the effective management of pine invasions. With infinite numbers of invaders and limited funds to dedicate to their control, a method of triaging species for management is critical. This is particularly difficult viii when information is typically biased towards invaders that are already widespread. By focussing on the ecological impacts of invaders it becomes possible to rank species on the basis of the threat they pose to native communities. Ecological research is capable of providing the knowledge to quantify invasion impacts and must remain at the centre of policy decisions.

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32

Minchin, Rhys. "Effect of a Trichoderma bio-inoculant on ectomycorrhizal colonisation of Pinus radiata seedlings." Lincoln University, 2010. http://hdl.handle.net/10182/1751.

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Ectomycorrhizal colonisation potential of Pinus radiata seedlings inoculated with the commercially available Trichoderma species bio-inoculant, Arbor-Guard™, was investigated in a commercial containerised nursery setting and in a separate glasshouse experiment, which included the co-inoculation of specific ectomycorrhizal fungi. Application of Arbor-Guard™ to Pinus radiata seedlings in a containerised commercial nursery had no significant effect on the ability of the naturally occurring ectomycorrhizal (ECM) fungi to colonise the seedlings. Thelephora terrestris was the dominant ectomycorrhizal species colonising the P. radiata root tips and has been described as a species able to rapidly outcompete other ECM species colonisation, particularly in high organic matter media like that used at the containerised commercial nursery investigated. In a similar experiment run to augment the commercial experiment, specific ECM fungi identified as Rhizopogon roseolus, Suillus luteus, and Rhizopogon villosulus were co-inoculated with Arbor-Guard™ to investigate the effect on the colonisation potential of the respective ECM species in combination with Trichoderma. The treatment effect of the addition of Arbor-Guard™ did not negatively impinge on the ECM species found, or the abundance of ECM root tips colonising the P. radiata seedlings. Ectomycorrhizal species in the Thelephoraceae family were the dominant species found colonising the P. radiata root tips. Of the inoculated ECM, S. luteus was the only detected species colonising the P. radiata root tips but was only found in low abundance. Non-conducive abiotic factors for optimum ECM colonisation were considered the most likely reason for the low colonisation of the inoculated ECM species. Any effect of the unintentional co-inoculation of the wood decaying fungi Hypholoma fasciculare and Lentinula edodes, due to misidentification, with the inoculated ECM species was unable to be resolved in this study. However, it was speculated that H. fasciculare may have had a negative effect on the inoculated ECM species colonisation. In vitro dual culture assays were initiated to investigate the specific interactions between each of the candidate ECM fungi inoculated in the glasshouse experiment when challenged with each of the six Trichoderma isolates in Arbor-Guard™. Both competition for nutrients and/ or space were concluded to be the main antagonistic mechanisms potentially used by five of the Trichoderma isolates against all co-inoculated ECM species and L. edodes. Hypholoma fasciculare was not inhibited by the five Trichoderma isolates, however, one Trichoderma isolate (LU 663) competitively antagonised all inoculated ectomycorrhizal/ saprophytic species before the mycelial fronts converged. Agar diffusible secondary metabolites were speculated to be potential mechanism of antagonism expressed by LU 663 over volatile antibiotics such as 6-pentyl-α-pyrone. No direct correlation could be dervived from the in vitro dual culture assays and what was observed in the containerised in planta results. Overall the results indicated no negative impact of the Trichoderma bio-inoculant Arbor-Guard™ on ectomycorrhizal colonisation of Pinus radiata seedlings in a containerised nursery system.

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33

McDonald, Timothy Myles. "Making sense of genotype x environment interaction of Pinus radiata in New Zealand." Thesis, University of Canterbury. School of Forestry, 2009. http://hdl.handle.net/10092/3222.

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In New Zealand, a formal tree improvement and breeding programme for Pinus radiata (D.Don) commenced in 1952. A countrywide series of progeny trials was progressively established on over seventy sites, and is managed by the Radiata Pine Breeding Company (RPBC). Diameter at breast height data from the series were used to investigate genotype x environment interaction with a view to establishing the need for partitioning breeding and deployment efforts for P. radiata. Nearly 300,000 measurements made this study one of the largest for genotype x environment interaction ever done. Bivariate analyses were conducted between all pairs of sites to determine genetic correlations between sites. Genetic correlations were used to construct a proximity matrix by subtracting each correlation from unity. The process of constructing the matrix highlighted issues of low connectivity between sites; whereby meaningful correlations between sites were established with just 5 % of the pairs. However, nearly two-thirds of these genetic correlations were between -1.0 and 0.6, indicating the presence of strong genotype x environment interactions. A technique known as multiple regression on resemblance matrices was carried out by regressing a number of environmental correlation matrices on the diameter at breast height correlation matrix. Genotype x environment interactions were found to be driven by extreme maximum temperatures (t-statistic of 2.03 against critical t-value of 1.96 at 95 % confidence level). When tested on its own, altitude was significant with genetic correlations between sites at the 90 % confidence level (t-statistic of 1.92 against critical t-value of 1.645). In addition, a method from Graph Theory using proximity thresholds was utilised as a form of clustering. However, this study highlighted the existence of high internal cohesion within trial series, and high external isolation between trial series. That is, grouping of sites (in terms of diameter) was observed to be a reflection of the series of trials for which each site was established. This characteristic is particularly unhelpful for partitioning sites into regions of similar propensity to genotype x environment interaction, as the genotype x environment effect is effectively over-ridden by the genotype effect. Better cohesion between past, present and future trial series, and more accurate bioclimatic data should allow more useful groupings of sites to be extracted from the data. Given this, however, it is clear that there are a large number of interactive families contained in the RPBC dataset. It is concluded that partitioning of New Zealand’s P. radiata breeding programme cannot be ruled out as an advantageous option.

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34

Hanstad, Janet Ann. "From Point Lobos to Jack's Peak : diversity in native populations of Pinus radiata /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2004. http://uclibs.org/PID/11984.

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35

Williams, Moira Caroline. "The ecological impacts of invasive Pinus radiata in eucalypt vegetation: pattern and process." Thesis, The University of Sydney, 2007. http://hdl.handle.net/2123/2761.

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Early recognition of plant invaders is key to their successful management. Yet knowledge of the ecological impacts of species before they become widespread is poor. This thesis examines the ecology of invasive Pinus radiata, a species which is known to spread from introduced plantings in Australia but is currently a low profile invader. Pinus invasions are considered major ecological problems in New Zealand and South Africa where wildlings are beginning to dominate natural areas and suppress native vegetation. Invasion success elsewhere and the large softwood estate in Australia suggest that pines may begin to dominate native eucalypt forests bordering large commercial plantations. This research focused on three components of impact of P. radiata; extent, abundance and effect per individual. The borders of 29 P. radiata plantations in NSW were surveyed in order to quantify the current level of invasion and to identify factors facilitating pine spread. Of particular interest was the role of propagule pressure, vegetation type and fire in the invasion process. The area of land in NSW currently invaded by P. radiata was estimated at almost 4 500 ha, although this is likely to be an underestimate due to an inability to detect wildlings (self-sown pines) at long distances from the plantation. Twenty six of the 29 plantations produced wild pines, however most of the sites are in the very early stages of invasion. Noticeable wildling populations were recorded at nine sites indicating that P. radiata is capable of establishing within native vegetation. Pine spread was most severe in the world heritage listed Blue Mountains region where pine densities reached up to 2000 per hectare in areas adjacent to the plantation and isolated pines were recorded up to 4 km from the source. The presence of isolated pines within intact native vegetation suggests that disturbance is not required for pine establishment in forested environments. Furthermore, high pine emergence and survival rates in eucalypt woodland and evidence of self reproduction by wildlings suggest that in the absence of adequate control measures pines may become established invaders in the Australian landscape. While low levels of current invasion at many sites hindered the ability to examine the factors facilitating invasion some variables that appear to be driving pine success were identified. At the landscape scale plantation size and residence time were significant predictors of the level of invasion at a site. Areas of native vegetation vi adjacent to plantations less than 40 years experienced very low levels of invasion suggesting a lag period between plantation establishment and invasion. However, pines with diameters up to 60 cm were observed growing adjacent to plantations younger than 40 years implying that the first colonisers are capable of establishing soon after plantation trees become reproductive. Propagule pressure was also found to have a strong influence on invasion success on a smaller scale manifesting in a significant positive relationship between the age of a plantation compartment and the likelihood of invasion. A negative relationship between plantation size and level of invasion was a surprising result and was influenced by just two large sites that happened to be located in areas of high rainfall. All sites receiving more than 1300 mm annual rainfall experienced low levels of invasion suggesting that this is a limiting factor for pine spread in NSW. There were significant differences in the level of invasion between vegetation types implying that some communities are more susceptible to invasion. Patterns of spread confirmed ideas regarding the facilitative effect of disturbance in the invasion process and the resistance of wet sclerophyll forest to invasion in Australia. An absence of wildlings in cleared land and areas of remnant bushland was attributed to high levels of grazing pressure. Wind direction did not appear to influence the distribution of pines close to the plantation, but evidence of long distance wind dispersal of pines was provided by an investigation of pine spread from the air at one site where large pines were found growing 10 km downwind from a mature plantation. Fire was found to have both a positive and negative influence on the invasion process. High intensity wildfires are capable of destroying large pines with diameters exceeding 50 cm. However, fire can stimulate seed release from cones resulting in large post-fire recruitment pulses. Seedling densities of up to 3050 per hectare were recorded almost 3 years after wildfire, suggesting that follow up control prior to recruits reaching coning age, i.e. within 5 years, would be beneficial. Surveys of wildling pines exposed to low intensity hazard reduction burns suggest that the majority of pines greater than 3 m in height and with a diameter of more than 10 cm will survive the fire. Low intensity prescribed fires that are carried out after pines have reached this size will fail to control wildling populations. To examine the influence of P. radiata once it has established in the native community this study focused on two mechanisms of impact, the addition of pine litter and increased shade due to an increase in canopy cover. Collection of pine litterfall vii within an invaded eucalypt woodland over a 2 year period recorded rates of up to 1400 kg/ha/year in the most heavily invaded area with a pine basal area of 11.3m2/ha. More than 70 % of pine litter fell directly below the pine canopy suggesting that the most severe litter effects will be limited to these areas. Glasshouse and field experiments were conducted to examine the influence of this increased litter load on the emergence of P. radiata and two native species. Recruitment of native plant species was impeded by litter levels of 6000 kg/ha, the equivalent of approximately 4 years of pine litterfall. Both P. radiata and the two natives responded similarly to pine and eucalypt litter suggesting the two litter types are influencing the recruitment phase equally. However, where pines are added to the system, increased litterfall rates could potentially result in the doubling of the litter load and hence a greater barrier to seedling establishment. Pine invaded eucalypt woodlands are also subjected to three fold increases in canopy cover. Trends in reduced emergence of native species under a pine canopy suggest that the addition of pines to eucalypt forests is likely to have a negative influence on native recruitment and may result in a shift towards a shade tolerant community. However, reversal of trends in emergence below pine canopy between seasons implies that quantifying invasion impacts requires a consideration of temporal variation. Increased levels of disturbance, forest fragmentation and an increasing pine estate are likely to lead to the infestation of new areas. Furthermore the lag phase associated with pine spread means that even if no new plantations are established the number of invasion events will increase. This study has identified a number of risk factors that can be used to guide plantation establishment and the management of invasion events. Minimising disturbance at plantation borders and increasing the ‘no planting’ zone will help to reduce the impacts of pines. Where possible new plantations should be established upwind of cleared land or at least, wet sclerophyll forest. Frequent monitoring of the borders of plantations yet to source invasions, particularly those greater than 40 years of age, will help identify problem areas before control becomes difficult and costly. Maps of the 29 plantations marked with areas of pine infestation will help prioritise sites for control and provide base level knowledge for future monitoring of pine spread. Stringent legislation that binds plantation managers to control wildlings beyond their boundaries is critical for the effective management of pine invasions. With infinite numbers of invaders and limited funds to dedicate to their control, a method of triaging species for management is critical. This is particularly difficult viii when information is typically biased towards invaders that are already widespread. By focussing on the ecological impacts of invaders it becomes possible to rank species on the basis of the threat they pose to native communities. Ecological research is capable of providing the knowledge to quantify invasion impacts and must remain at the centre of policy decisions.

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36

Kirongo, Balozi Bekuta. "Modelling growth responses of juvenile radiata pine (Pinus radiata D. Don) clones subjected to different weed competition levels in Canterbury, New Zealand." Thesis, University of Canterbury. Forestry, 2000. http://hdl.handle.net/10092/7496.

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For a given site, species, genotype and management regime, tree growth is related to the amount, and temporal- and spatial-distribution of foliage, as governed by the prevailing below- and above-ground environment and intercepted photosynthetically active radiation. Canopy foliage budgets, therefore can provide first hand information about how trees cope with adverse environmental conditions and resource deficits in more subtle ways than height and diameter which are not as sensitive to changes in resource availability as leaf area. Process-oriented research, aimed at quantifying needle mortality within canopies and foliage growth dynamics of young radiata pine clones growing under varying competition gradients, therefore has the potential to improve decision tools for foresters charged with establishing tree crops. During this study growth responses of juvenile radiata pine (Pinus radiata D. Don) clones to variable weeding micro-environments during the first 3 years after outplanting were evaluated. The study was established in a dry site on the Canterbury plains of the South Island of New Zealand. A complete randomised block design replicated three times in a split-plot layout was used. Four weeding treatments; 1) complete weeding, 2) 2 m diameter spots, 3) 1 m diameter spots around plants and 4) a control, formed the main plots while seven clones formed the sub-plots. Leaf area and specific leaf area spatial distribution as well as fascicle mortality in time and space were quantified. Annual crown foliage budgets of 3 of the clones were evaluated using regressions developed from limited destructive sampling and image analysis techniques. Changes in mean relative growth rate (RGR) with tree size and age were evaluated by quantifying the morphological and physiological terms of the RGR expansion, to allow for changes in these terms; RGR = ULR * SLA * LWR where, RGR = relative growth rate, ULR = unit leaf rate, SLA = specific leaf area and LWR = leaf weight ratio. Relative growth rate declined with tree age and size for trees in all weeded treatments but increased with age and size for trees in the unweeded control. The decline in RGR was mainly due to reduced ratio of dry matter turn over to leaf area i.e. unit leaf rate. Of tree age and size, size was the major factor influencing the decline in RGR. Of the 3 clones studied in detail, clone 3 had a different above ground carbon allocation strategy to clones 1 and 2, especially as regards leaf weight ratio and leaf area ratio. Weeding influenced tree growth considerably. Significant clonal differences in height and basal-basal area were found. Trees growing in weed-free environments made favourable use of their micro-environments and significant genotype-by weeding interaction was present for height. However, no "rich-kid" effect (some trees growing in weed-free micro-environments performing poorly) was found. Provisional models of height, basal-basal area and tree survival integrating weeding and clonal effects were also developed. One of the significant findings from this study was the strong evidence against the constant RGR model which has been used by many researchers of tree growth analysis. The results further demonstrated that trees growing with weeds were predisposed to perform poorly due to reduced canopy production as well as having higher proportions of older, less efficient foliage. The results from this study lay the framework to explicitly quantify clonal responses to resource deficits arising from management inputs using variables directly involved in canopy production (i.e. leaf area).

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37

Walbert, Katrin. "Ectomycorrhizal communities associated with a Pinus radiata plantation in the North Island, New Zealand." Lincoln University, 2008. http://hdl.handle.net/10182/658.

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Aboveground and belowground ectomycorrhizal (ECM) communities associated with different age classes of the exotic plantation species Pinus radiata were investigated over the course of two years in the North Island of New Zealand. ECM species were identified with a combined approach of morphological and molecular (restriction fragment length polymorphism (RFLP) and DNA sequencing) analysis. ECM species richness and diversity of a nursery in Rotorua, and stands of different ages (1, 2, 8, 15 and 26 yrs of age at time of final assessment) in Kaingaroa Forest, were assessed above- and belowground; furthermore, the correlation between the above- and belowground ECM communities was assessed. It was found that the overall and stand specific species richness and diversity of ECM fungi associated with the exotic host tree in New Zealand were low compared to similar forests in the Northern Hemisphere but similar to other exotic plantations in the Southern Hemisphere. Over the course of this study, 18 ECM species were observed aboveground and 19 ECM species belowground. With the aid of molecular analysis the identities of Laccaria proxima and Inocybe sindonia were clarified. In the aboveground study, five species were found associated with P. radiata that were previously not reported with this host in New Zealand (Inocybe sindonia, Lactarius rufus, Lycoperdon gunii, Rhizopogon pseudoroseolus and Wilcoxina mikolae). Belowground, the species Psudotomentella sp., P. tristis, R. luteorubescens, Tomentella sp., Wilcoxina mikolae were found as new associates of P. radiata in New Zealand, additionally nine ECM types were found that could not be identified with molecular analysis. There was little correlation between the species fruiting and the species colonising root tips. Only seven species were found in common between the above- and belowground communities, furthermore the dominant species aboveground were not observed in the belowground ECM communities. The influence of host age on the above- and belowground ECM communities of different age classes of P. radiata plantations was investigated. The aboveground species richness increased from the nursery to the oldest age group investigated (26 yrs), while diversity increased to the 15 yr old age group and decreased slightly to the oldest stand. A clear sequence of ECM species changes was observed to be related to stand age with a growing complexity over the chronosequence. The belowground ECM communities showed a different picture and richness and diversity initially decreased from the nursery to the outplanting but increased thereafter. Belowground no change in ECM composition that was directly related to the age of the host was observed, but two distinct groups of ECM species were found – a 'young' and a 'plantation forest' group, with the respective discriminating species being Rhizopogon rubescens and Type unknown Basidiomycete/Amanita muscaria. Another aspect of the study was the fate of the nursery ECM species in the outplanting and the arrival of non-nursery species. The ECM communities of seedlings in the nursery were investigated in 2006 and these seedlings were followed up over eight assessments in the field for one year, furthermore data from the 1-, 2 and 8 yr old plantation stands was analysed. It was found that the nursery species do survive the first year of outplanting and are dominant in the first year. The first non-nursery species occurred six months after outplanting but was only in minor abundance. Nursery ECM were dominant for two years after the seedlings were planted, and were completely replaced after seven years. Rhizopogon rubescens was found to be the most persistent and dominant species in the outplanting, facilitating the successful establishment of the seedlings in the plantation forest.

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38

Duran, Sandoval Alvaro Jorge. "Determination and characterization of the causal agent of Pinus radiata needle blight in Chile." Thesis, University of Pretoria, 2010. http://hdl.handle.net/2263/31415.

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The leaf and shoot blight disease known locally as Daño Foliar del Pino (DFP) is the most important problem affecting Chilean Pinus radiata plantations. The disease is typified by needle infections, exudation of resin at the bases of needle brachyblasts and necrotic lesions in the cambium of younger trees, which eventually girdle branches. The disease causes death of seedlings young trees and mature trees can also succumb after a few years of successive infection. DFP emerged very recently and its cause was unknown. Studies that make up this thesis led to the identification of the causal agent of DFP, which was described as the new species Phytophthora pinifolia A. Durán, Gryzenh. & M.J. Wingf. This is the first discovery of a Phytophthora sp. infecting needles and shoots of a Pinus sp. anywhere in the world. Two diagnostic procedures were developed to screen large numbers of samples rapidly and cost effectively for the pathogen. Population genetic studies showed that the P. pinifolia population in Chile is a single clonal lineage that exists in the absence of sexual recombination. This suggests strongly that P. pinifolia is an introduced pathogen in Chile although its origin and natural host-range is uknown. In order to promote effective management of P. pinifolia, three fungicides were screened in vitro and in planta. Mefenoxam was shown to be the most effective compound, also providing the most consistent results. DFP is recognized as one of the most important disease problems to strike non-native pine plantation forestry in recent times. Studies in this thesis represent the first ever on the disease and its causal agent and they provide a foundation for the many studies that must follow to ensure that P. pinifolia does not lead to disease disasters elsewhere in the world.
Thesis (PhD)--University of Pretoria, 2010.
Microbiology and Plant Pathology
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39

Camacho, Focacci Felipe Ignacio. "Productividad primaria bruta y neta en plantaciones de Pinus radiata D. Don en la Región del Bío Bío, Chile." Tesis, Universidad de Chile, 2016. http://repositorio.uchile.cl/handle/2250/150827.

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Memoria para optar al Título Profesional de Ingeniero Forestal
Se realizaron inventarios forestales mensuales y mediciones fisiológicas trimestrales en plantaciones de Pinus radiata D. Don en la Región del Bío Bío en las cuatro principales zonas de crecimiento para esta especie (IV, V, VI y VII) durante 24 meses entre Agosto de 2010 y Agosto de 2012. Los predios donde se ubicaron los ensayos fueron Lomas Coloradas en la Comuna de San Pedro de la Paz, Nacimiento en la Comuna de Nacimiento, Santa Bárbara en la Comuna de Santa Bárbara y Tapihue en la Comuna de Cabrero. Para cada sitio se consideraron tres clases de edad (0-7, 7-14 y 14+ años). En cada uno de las 12 instancias de Zona-Edad, se procedió a instalar un conglomerado de 3 parcelas permanentes de 1.000 m2, totalizando 36 parcelas. Estos predios y rodales se ubicaron a menos de 10 km de las estaciones meteorológicas de Escuadrón (Lomas Coloradas), Pichún (Nacimiento), Santa Bárbara (Santa Bárbara) y Trilahue (Tapihue), pertenecientes a Forestal Mininco S.A.

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40

Rojas, Retamal Emilio Arturo. "Índice de área foliar en plantaciones de Pinus radiata D. Don en la la Región del Bío Bío, Chile." Tesis, Universidad de Chile, 2014. http://repositorio.uchile.cl/handle/2250/151645.

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Memoria para optar al Título Profesional de Ingeniero Forestal
Se midió mensualmente el índice de área foliar en plantaciones de Pinus radiata D. Don en la región del Bío Bío en las cuatro principales zonas de crecimiento para esta especie (IV, V, VI y VII) durante 24 meses entre Octubre de 2010 y Octubre de 2012. Los predios donde se ubicaron los ensayos fueron San Pedro de la Paz (predio Lomas Coloradas), Nacimiento (predio Nacimiento), Santa Bárbara (predio Santa Bárbara) y Cabrero (predio Tapihue). Para cada sitio se consideraron tres clases de edad ([0-7), [7-14) y [14+)). En cada uno de los 12 puntos de Zona-Edad, se procedió a instalar un conglomerado de 3 parcelas permanentes de 1.000 m2, totalizando 36 parcelas, entre los meses de Agosto y Septiembre de 2010. Estos predios y rodales se ubican a menos de 10 km de las estaciones meteorológicas de Escuadrón (Lomas Coloradas), Pichún (Nacimiento), Santa Bárbara (Santa Bárbara) y Trilahue (Tapihue) que mantiene Forestal Mininco S.A. La edad se correlacionó positivamente con el índice de área foliar (L) como era de esperar. Además se aprecia que el L crece fuertemente desde la clase de edad [0-7) a la [7-14), comparado con el crecimiento entre la clase de edad [7-14) a [14+). Lo anterior implica que el mayor crecimiento en área foliar se genera antes de los 14 años. Además a lo largo de los 24 meses se observa que el L aumenta fuertemente en la clase de edad [0-7), en menor cuantía en la clase de edad [7-14), y muestra un crecimiento prácticamente imperceptible en la clase [14+) años.

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41

Ferguson, George. "Calculating the potential increase in Pinus radiate stem value through selection for higher stiffness." Thesis, University of Canterbury. School of Forestry, 2014. http://hdl.handle.net/10092/10464.

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New Zealand grown Pinus radiata is limited in its application for structural purposes by its stiffness deficiencies. This dissertation aims to estimate potential improvements in stem value through selection for improved stiffness. A new method to model and value volumes of structural wood grades within a stem was used to calculate these value improvements. Data for each stem from a stand in Kaingaroa Forest bred for improved wood quality was used to perform this analysis. This data was from a stand bred for improved wood quality and included information on the stiffness, density and width of each growth ring for each stem. The data was in the form of cores. Height and volume data was not recorded and therefore needed to be modelled. The volumes of MSG8, MSG11 and MSG13 wood were estimated by modelling the stem volume at the age when wood is produced that is stiff enough to qualify for each grade. The majority of stems had merchantable volumes between 1-2.5m3 with the largest stems containing 3.6m3. Average stiffness ranged between 5.2GPa and 11.3GPa with the stand average being 8.4GPa. There was no relationship between average stiffness and merchantable volume. Stem values were found to range between $60-$131/m3 with the stand average being $91/m3. The 10 most valuable stems had a total stem value ($318) twice that of the stand average ($157). The most valuable stem ($411) showed a 160% increase in stem value from the average. The increases in value/m3 were caused by large increases in the proportion of MSG11 and MSG13 wood held within the merchantable volume. These potential gains in stem value could help tree breeders assign an accurate economic weighting to stiffness improvements. Forest managers wanting to justify using a more expensive, improved stiffness seedlot may also find these results valuable.

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42

Ramírez, Farfán Álvaro Felipe. "Comportamiento al biodeterioro de madera de pino radiata (Pinus radiata D.Don) tratado con cobre-azol (CA-B), contra hongos de pudrición y termita subterránea." Tesis, Universidad de Chile, 2017. http://repositorio.uchile.cl/handle/2250/151377.

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Memoria para optar al Título Profesional de Ingeniero Forestal
La madera de pino radiata, principal recurso maderero del país, es de baja durabilidad. Hongos e insectos, entre otros factores de su deterioro, son usualmente los más relevantes. Del grupo de los insectos, en particular la termita subterránea “Reticulitermes flavipes”, representa hoy la mayor preocupación, por su agresividad y avance permanente en áreas pobladas del país. El arseniato de cobre cromado (CCA) fue, por décadas, el preservante más utilizado en todo el mundo para proteger la madera, sin embargo, preocupaciones medioambientales, hace más de diez años, dieron paso a un cambio hacia otros productos. El uso de cobreazoles (CA) y en particular el de tipo B, junto con cobreazol micronizado, han sido los cambios más importantes desde entonces a nivel mundial. Su incorporación al mercado local, sin embargo, ha sido muy lenta, básicamente por costo y por no existir un marco legal que regule el uso de madera tratada con CCA. Sobre la base de los requisitos exigidos por la Australian Standard®, AS 1604.1-2012, para madera tratada con CA-B, el objetivo del estudio fue evaluar el comportamiento de madera de Pino radiata tratada con CA-B, a retenciones menores a las exigidas por la Norma Chilena, frente al ataque de hongos de pudrición y termita subterránea. Los métodos empleados fueron; “Standard Test Method for Wood Preservatives by Laboratory Soil-Block Cultures”, descrito en la ASTM Designation: D1413 − 07ɛ1 y la Norma Chilena NCh 3060.Of 2007, para el estudio con hongos y termita subterránea respectivamente. En el estudio con Lentinus lipideus, todos los grupos de retención presentaron efecto positivo en el control del hongo y diferencias estadísticamente significativas respecto a las probetas testigo. En el caso de Coriolus versicolor, solo los grupos de retención 1,4 y 1,8 kg/m3 se diferenciaron estadísticamente del testigo en el control del hongo. En el estudio contra termita subterránea, la retención necesaria de CA-B para el control de Reticulermes flavipes se ubicó entre las retenciones 1,4 y 1,8 kg/m3 (concordante con la Norma NCh 819:2012). Una retención menor en pino radiata tratado con CA-B, no pudo ser validada para el control de termita subterránea, Reticulermes flavipes.

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Basilio, Paula Rachel Rabelo Correa. "Caracterizaçao de isolados de Sphaeropsis sapinea e avaliaçao da resistencia em progenies de Pinus radiata." reponame:Repositório Institucional da UFPR, 2013. http://hdl.handle.net/1884/15879.

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Sphaeropsis sapinea é conhecido como um importante patógeno de várias espécies de Pinus, causando a seca de ponteiros e a morte de árvores em plantios comerciais. Esse patógeno foi introduzido no Brasil, provavelmente, durante as introduções do gênero Pinus. Seu primeiro relato ocorreu na década de 1940, com os primeiros plantios de P. radiata no estado de São Paulo, os quais foram dizimados. Um projeto de reintrodução dessa espécie florestal no Brasil foi delineado para a seleção de famílias de P. radiata resistentes a S. sapinea. Desse modo, este estudo objetivou a caracterização morfológica, molecular e patogênica de isolados de S. sapinea, para escolher os isolados mais agressivos para uso na seleção de material resistente. Quatro isolados da região Sul do Brasil foram obtidos e a caracterização morfológica e patogênica indicou que os isolados estudados pertencem ao morfotipo “A” de S. sapinea. Houve diferenças na agressividade e na diversidade genética dos isolados em todos os testes in vitro e in vivo. A maior herdabilidade de P. radiata para tamanho das lesões foi obtida com o isolado SS1.3 (H2 M = 0,3357870), enquanto que para secamento dos ponteiros a maior herdabilidade foi obtida com o isolado SS2.4 (H2 M = 0,256347). Os resultados mostraram a possibilidade de seleção precoce de material resistente à seca de ponteiros em mudas de P. radiata

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Slui, Benjamin Thomas. "The effect of plot co-registration error on the strength of regression between LiDAR canopy metrics and total standing volume in a Pinus radiata forest." Thesis, University of Canterbury. School of Forestry, 2014. http://hdl.handle.net/10092/10460.

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Background: The objective of this study was to verify the effect that plot locational errors, termed plot co-registration errors, have on the strength of regression between LiDAR canopy metrics and the measured total standing volume (TSV) of plots in a Pinus radiata forest. Methods: A 737 hectare plantation of mature Pinus radiata located in Northern Hawkes Bay was selected for the study. This forest had been measured in a pre-harvest inventory and had aerial LiDAR assessment. The location of plots was verified using a survey-grade GPS. Least square linear regression models were developed to predict TSV from LiDAR canopy metrics for a sample of 204 plots. The regression strength, accuracy and bias was compared for models developed using either the actual (verified) or the incorrect (intended) locations for these plots. The change to the LiDAR canopy metrics after the plot co-registration errors was also established. Results: The plot co-registration error in the sample ranged from 0.7 m to 70.3 m, with an average linear spatial error of 10.6 m. The plot co-registration errors substantially reduced the strength of regression between LiDAR canopy metrics and TSV, as the model developed from the actual plot locations had an R2 of 44%, while the model developed from the incorrect plot locations had an R2 of 19%. The greatest reductions in model strength occurred when there was less than a 60% overlap between the plots defined by correct and incorrect locations. Higher plot co-registration errors also caused significant changes to the height and density LiDAR canopy metrics that were used in the regression models. The lower percentile elevation LiDAR metrics were more sensitive to plot co- registration errors, compared to higher percentile metrics. Conclusion: Plot co-registration errors have a significant effect on the strength of regressions formed between TSV and LiDAR canopy metrics. This indicates that accurate measurements of plot locations are necessary to fully utilise LiDAR for inventory purposes in forests of Pinus radiata.

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Zoric, Branislav. "Modelling the influence of stocking on longitudinal and radial variation in wood properties of Pinus radiata on a warm Northland site." Thesis, University of Canterbury. School of Forestry, 2009. http://hdl.handle.net/10092/2564.

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The objective of this study was to determine how final stocking influences tree growth and radial and longitudinal variation in wood properties at a Pinus radiata D. Don plantation located at one of the warmest forest sites in New Zealand, Forsyth Downs forest in Northland. This thesis addressed both the effect of stocking on stand basal area, height, diameter and branch diameter and the effect of stocking on wood properties microfibril angle (MFA), module of elasticity and density. Finally, how ring width influences wood properties and whether this variable accounts for the treatment effects was investigated. Stocking, height and ring number and all interactions between these variables significantly affected ring width. Ring width by itself was significant as a predictor of density, but when it was combined with other class level variables it was insignificant (i.e. does not account for treatment effects), and it did not add anything to a model with only class effects. There was a significant impact of ring number on density while ring width was insignificant in the same model. MFA was significantly affected by ring width, height and ring number in the tree, and all interactions, apart from the three way interaction, but not by stocking. Ring width was significant in the MFA model both by itself and when it was combined with other variables. Ring width accounted for the stocking effect. The best model of MOE included the class level effects of stocking, height and ring number within the tree, and all interactions between these variables, and ring width, as a continuous variable. While there was a significant effect between stockings this was relatively weak compared to the other main effects. Ring width largely accounted for the effect of stocking, but not that of ring number, or height.

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Van, Zyl Salmon Johannes. "Biomass potential and nutrient export of mature pinus radiata in the southern Cape region of South Africa." Thesis, Nelson Mandela Metropolitan University, 2015. http://hdl.handle.net/10948/4321.

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South Africa lags behind the rest of the world with regard to the availability of allometric biomass information. There is a complete lack of site specific allometric data for Pinus radiata in the southern Cape region, impeding investment in the renewable energy sector. This shortcoming was addressed by developing up-scalable, single tree biomass models. These models quantify the aboveground biomass of rotation age P. radiata grown in the southern Cape across a range of site conditions. The models use diameter at breast height (DBH) to predict the aboveground component biomass. A nutrient loss risk potential was assigned to each biomass component. Nineteen trees were destructively harvested using a full fresh weight sampling approach. Basic density was determined using a water displacement method, while Newton’s volume equation was used for stemwood volume determination. Log linear models were simultaneously regressed through seemingly unrelated regression (SUR) using the “Systemfit” R statistical package to force component additivity. A categorical variable was applied to the models, grouping the data into two Site Index (SI) based categories, namely “Low” SI and “Medium to High” SI, to account for inter-site variability. The corrected Akaike Information Criteria (AICc) and coefficient of determination (R2) was used to determine the goodness of fit of the models. The McElroy R2 for the SUR system was 0.95. Biomass models were developed that are able to predict various tree component masses at high levels of certainty within site and stand attribute ranges similar to this study. The importance of accurate, site specific wood basic density was demonstrated by its substantial weighting on stem and hence total biomass. Results showed that the stemwood mean basic density range was between 503 kg m-3 and 517 kg m-3 for the “Low” SI sites and 458 kg m-3 for the “Medium to High” SI sites. Site quality can have a major impact on the models, particularly on poorer sites where stemwood production is proportionally less than other tree components. Total aboveground biomass was estimated to range between 58.61 odt ha-1 and 70.85 odt ha-1 for “Low” SI sites, and 185.31 odt ha-1 to 266.58 odt ha-1 for “Medium to High” SI sites. Stemwood biomass accounted for 65% of the total aboveground biomass for “Low” SI sites and 70% for “Medium to High” SI sites.

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Pagliarini, Maximiliano Kawahata. "Genotype by environment interaction in slash pine and methodologies comparison for radiata pine wood properties /." Ilha Solteira, 2016. http://hdl.handle.net/11449/141895.

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Orientador: Ananda Virginia de Aguiar
Abstract: Exotic forest species have been introduced in Brazil in order to promote improvements in socioeconomic development and help to reduce the pressure caused to native forests. With growing demand for these species, research on genetic improvement has increased to find new, more productive germplasm and preferably in less time. Two species were used in the study: slash pine (Pinus elliottii Engelm. var. elliottii) and radiata pine (Pinus radiata D. Don). The first part of the study had the purpose to identify the stability, adaptability, productivity and genetic parameters, in addition to selection gain and genetic divergence in slash pine open pollinated second generation progenies considering phenotypic trait. Two tests were established, one in Ponta Grossa-PR with 24 progenies and one in Ribeirão Branco-SP with 44 progenies, both in Brazil, to identify the most productive genotypes for commercial planting areas in both sites. There was significant variation (p<0.01) among progenies for growth and form traits. The high coefficients of genetic variation for wood volume (14.31% to 16.24% - Ribeirão Branco-SP and 31.78% to 33.77% - Ponta Grossa-PR) and heritability (0.10 to 0.15 – Ribeirão Branco-SP and 0.36 to 0.48 – Ponta Grossa-PR) have shown low environmental influence on phenotypic variation, which is important for the prediction of genetic gain by selecting and confirming genetic potential in both places, especially Ponta Grossa. The effect of genotype x environment interact... (Complete abstract click electronic access below)
Resumo: Espécies exóticas de Pinus foram introduzidas no Brasil para promoverem o crescimento socioeconômico do país e ajudar na redução da pressão causada pelo uso de florestas nativas Com a crescente demanda por essas espécies, pesquisas em melhoramento genético tem aumentado na busca de novos germoplasma mais produtivos em menor tempo. Duas espécies foram utilizadas no presente trabalho: Pinus elliottii Engelm. var. elliottii e Pinus radiata D. Don. A primeira parte do trabalho teve a finalidade de identificar a estabilidade, a adaptabilidade, a produtividade e os parâmetros genéticos, além do ganho de seleção e diversidade genética em progênies de polinização aberta de segunda geração de P. elliottii var. elliottii considerando os caracteres fenotípicos. Foram estabelecidos dois testes, um em Ponta Grossa-PR com 24 progênies e outro em Ribeirão Branco-SP com 44 progênies visando identificar os genótipos mais produtivos para áreas de plantio comercial em ambos locais. Foi observada variação significativa (p<0,01) entre as progênies para os caracteres de crescimento e alguns caracteres de forma. Os altos coeficientes de variação genética para volume de madeira (14,31% a 16,24% - Ribeirão Branco e 31,78% a 33,77% - Ponta Grossa) e herdabilidade (0,10 a 0,15 – Ribeirão Branco e 0,36 a 0,48 – Ponta Grossa) mostraram baixa influência do ambiente na variação fenotípica, o que é importante para a predição do ganho genético mediante a seleção e confirmam potencial genético em ambos os loc... (Resumo completo, clicar acesso eletrônico abaixo)
Doutor

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Ow, Lai Fern. "Thermal acclimation of photosynthesis and respiration in Pinus radiata and Populus deltoides to changing environmental conditions." Thesis, University of Canterbury. Biological Sciences, 2008. http://hdl.handle.net/10092/2000.

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Although it has long been recognized that physiological acclimation of photosynthesis and respiration can occur in plants exposed to changing environmental conditions (e.g. light, temperature or stress), the extent of acclimation in different tissues (i.e. pre-existing and new foliage) however, has not received much attention until recently. Furthermore, few studies have investigated the extent of photosynthetic and respiratory acclimation under natural conditions, where air temperatures vary diurnally and seasonally. In this study, the effects of variations in temperature on respiratory CO2 loss and photosynthetic carbon assimilation were examined under both controlled and natural environments. The purpose of the investigations described in this thesis was to identify the effects acclimation would have on two key metabolic processes in plants exposed to temperature change, with emphasis also placed on the role of nutrition (nitrogen) and respiratory enzymatic characteristics on the potential for acclimation in two contrasting tree species, Pinus radiata and Populus deltoides. Controlled-environment studies (Chapter 2 and 3) established that rates of foliar respiration are sensitive to short-term changes in temperature (increasing exponentially with temperature) but in the longer-term (days to weeks), foliar respiration acclimates to temperature change. As a result, rates of dark respiration measured at any given temperature are higher in cold-acclimated and lower in warm-acclimated plants than would be predicted from an instantaneous response. Acclimation in new foliage (formed under the new temperature environment) was found to result in respiratory homeostasis (i.e. constant rates of foliar respiration following long-term changes in temperature, when respiration is measured at the prevailing growth temperature). Available evidence suggests that substantial adjustments in foliar respiration tend to be developmentally dependent. This may in part explain why respiratory homeostasis was only observed in new but not in pre-existing tissues. Step changes in temperature (cold and warm transfers) resulted in significant changes in photosynthetic capacity. However, in stark contrast to the findings of respiration, there was little evidence for photosynthetic acclimation to temperature change. The results obtained from field studies (Chapter 4) show that in the long-term over a full year, dark respiration rates in both tree species were insensitive to temperature but photosynthesis retained its sensitivity, increasing with increasing temperature. Respiration in both species showed a significant downregulation during spring and summer and increases in respiratory capacity were observed in autumn and winter. Thermal acclimation of respiration was associated with a change in the concentration of soluble sugars. Hence, acclimation of dark respiration under a naturally changing environment is characterized by changes in the temperature sensitivity and apparent capacity of the respiratory apparatus. The results from controlled and natural-environment studies were used to drive a leaflevel model (which accounted for dark respiratory acclimation) with the aim of forecasting the overall impact of responses of photosynthesis and respiration in the long term (Chapter 5). Modellers utilise the temperature responses of photosynthesis and respiration to parameterize carbon exchange models but often ignore acclimation and use only instantaneous responses to drive such models. The studies here have shown that this can result in erroneous estimates of carbon exchange as strong respiratory acclimation occurs over longer periods of temperature change. For example, it was found here that the failure to factor for dark respiratory acclimation resulted in the underestimation of carbon losses by foliar respiration during cooler months and an overestimation during warmer months - such discrepancies are likely to have an important impact on determinations of the carbon economy of forests and ecosystems. The overall results substantiate the conclusion that understanding the effect of variations in temperature on rates of carbon loss by plant respiration is a prerequisite for predicting estimates of atmospheric CO2 release in a changing global environment. It has been shown here that within a moderate range of temperatures, rate of carbon uptake by photosynthesis exceeds the rate of carbon loss by plant respiration in response to warming as a result of strong respiratory acclimation to temperature change. This has strong implications for models which fail to account for acclimation of respiration. At present, respiration is assumed to increase with increasing temperatures. This erroneous assumption supports conclusions linking warming to the reinforcement of the greenhouse effect.

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Lee, Justin Chee Vui. "Development of a predictive model for the hypochlorite bleaching of CE-prebleached Pinus radiata Kraft pulp." Thesis, University of Canterbury. Chemical and Process Engineering, 1990. http://hdl.handle.net/10092/8782.

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A study was done to determine the kinetics and stoichiometry of hypochlorite bleaching of pinus radiata kraft pulp obtained from the extraction stage of a chlorine, caustic extraction and hypochlorite (CEH) bleaching sequence. The "differential method" of experimentation was used, where bleaching chemicals are charged at the start of the experiment and allowed to decrease as bleaching proceeds. The bleaching rate is found to be dependent on temperature, chromophore concentration (approximated by the specific light absorption coefficient), hypochlorite ion concentration (OCl-) and hydroxide ion concentration (alkalinity, OH-). Bleaching rate increases with chromophore concentration and hypochlorite ion concentration but decreases with increasing alkalinity. The bleaching rate, [formula here], for the hypochlorite bleaching of CE-prebleached pinus radiata kraft pulp can be expressed by the following kinetic equation. [formula here] where Ck : specific light absorption coefficient at 457 nm, [m² kg-¹]. [OH-] : hydroxide ion concentration, [mol 1-¹]. [OCl-] : hypochlorite ion concentration, [mol 1-¹] and the Arrhenius' activation energy is approximately 64 kJ mol-¹ The stoichiometry of the bleaching reaction can be described by the following two equations. [formulas here] Where Cko : initial specific light absorption coefficient, [m²kg-¹] OCo : initial hypochlorite charge, [moles per kg O.D. pulp] OCl : hypochlorite charge at time=t, [moles per kg O.D. pulp].

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Lambert, M. J. "Stem breakage of Pinus radiata during mechanical felling in Kinleith Forest, Central North Island, New Zealand." Thesis, University of Canterbury. Forestry, 1996. http://hdl.handle.net/10092/10380.

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This report examines stem breakage of Pinus radiata as a result of mechanical felling in Kinleith forest. Four machines were studied, two Bell TF120 feller-bunchers and two Timbco T445 hydro-bunchers. The machines broke between 84% and 100% of the trees felled. Most causes of breakage could not be determined. Of that which could, falling trees striking stumps and previously felled logs accounted for the majority of the breakage. The machine operators and the machine types studied were deemed to be significantly different and thus separate breakage functions were derived for each operator and machine type. The breakage function currently used by Carter Holt Harvey Forests Kinleith, produced from manual felling data, was compared with the newly developed mechanical functions and found to be different. For this reason a mechanical breakage function was created. Nested analysis showed that most of the variation in relative break heights was due to differences in individual trees, not differences in machines or differences in operators. Two sets of statistically significant equations between height and machine type and the breakpoint variables diameter at the break point and relative break height were identified. Although the models account for some of the breakage, none of the relationships developed completely explain how the variables influence stem breakage. Further research is required into operator and the landing environment variables and how these affect felling breakage.

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Dissertations / Theses on the topic 'Pinus radiata'

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