O eucalipto é uma das espécies arbóreas mais plantadas no mundo atualmente, principalmente devido ao seu uso como matéria prima para as indústrias de celulose, papel e madeireira. Eucalyptus globulus e seus híbridos possuem baixos teores de lignina e despertam grande interesse da indústria, já que essa característica facilita e diminui o custo do processo de extração da celulose. Entretanto, essa espécie é recalcitrante ao enraizamento adventício, o que dificulta a propagação vegetativa de suas mudas. Com o objetivo de melhor entender os mecanismos moleculares envolvidos na recalcitrância ao enraizamento em E. globulus, o presente estudo envolveu análises de parâmetros morfológicos, anatômicos e moleculares durante a rizogênese adventícia nesta espécie. A exposição à auxina exógena reverteu o fenótipo recalcitrante em E. globulus, aumentando significativamente a porcentagem de enraizamento. O câmbio vascular foi identificado como uma região de acúmulo de auxina e local de origem das raízes adventícias. Através de análises da expressão gênica em células do câmbio, observou-se que TOPLESS e IAA12, repressores da sinalização de auxina, e ARR1, envolvido na rota de sinalização de citocininas, parecem atuar como reguladores negativos do enraizamento adventício. A alta expressão destes genes em plantas controle foi significativamente diminuída com aplicação de auxina exógena. Comparativamente, em espécie de fácil enraizamento, E. grandis, a expressão destes genes se manteve em níveis mais baixos em ambas as condições de tratamento, e a concentração de ácido indol-3-acético endógeno em plantas controle mostrou-se mais elevada. Análises do padrão proteico durante o enraizamento em plantas de E. globulus tratadas ou não com auxina exógena identificaram proteínas envolvidas em diversos processos biológicos, principalmente estresse oxidativo e metabolismo energético. Diferenças interessantes foram identificadas ao comparar as diferentes condições e fases do enraizamento. Várias proteínas foram claramente relacionadas com o respectivo fenótipo apresentado pela planta em cada situação, principalmente considerando plantas controle. Os resultados aqui apresentados representam avanços relevantes no conhecimento sobre a rizogênese adventícia em plantas lenhosas, podendo ser utilizados como ferramentas no desenho de estratégias visando melhorar o enraizamento em genótipos recalcitrantes de valor para a indústria. / Eucalyptus is one of the most planted tree species in the world today, mainly due to its use as raw material for paper, cellulose and wood industries. Eucalyptus globulus and its hybrids have low lignin contents and are of great interest to industry, as this feature facilitates and reduces costs of the cellulose extraction process. However, this species is recalcitrant to adventitious rooting, making vegetative propagation by cuttings difficult. Aiming at a better understanding of the molecular mechanisms involved in rooting recalcitrance in E. globulus, this study analyzed changes in morphological, anatomical and molecular patterns during adventitious rooting in this species. Exogenous auxin exposure reversed the recalcitrant phenotype in E. globulus, significantly increasing rooting percentage. The vascular cambium was identified as a region of auxin accumulation and also the site from where adventitious roots originated. Gene expression analysis in cambium cells indicated that TOPLESS and IAA12, auxin signaling repressors, and ARR1, involved in cytokinin signaling pathway, appear to act as negative regulators of adventitious rooting. The high expression of those genes in control plants was significantly decreased by exogenous auxin treatment. Comparatively, in an easy-to-root species, E. grandis, the expression of these genes was significantlylower in both treatment conditions, and the concentration of endogenous indole- 3-acetic acid in control plants was higher. Analysis of the protein pattern during rooting in E. globulus plants treated or not with exogenous auxin allowed the identification of proteins involved in diverse biological processes, mainly oxidative stress and energy metabolism. Interesting differences were identified when comparing different rooting conditions or phases. Several proteins were clearly associated with the respective plant phenotype in each situation, particularly considering control plants. These results represent relevant advances in the knowledge about adventitious rooting in woody plants and can be used as tools in the design of strategies aiming at improving adventitious rooting in recalcitrant genotypes of industrial value.

O eucalipto é uma das espécies arbóreas mais plantadas no mundo atualmente, principalmente devido ao seu uso como matéria prima para as indústrias de celulose, papel e madeireira. Eucalyptus globulus e seus híbridos possuem baixos teores de lignina e despertam grande interesse da indústria, já que essa característica facilita e diminui o custo do processo de extração da celulose. Entretanto, essa espécie é recalcitrante ao enraizamento adventício, o que dificulta a propagação vegetativa de suas mudas. Com o objetivo de melhor entender os mecanismos moleculares envolvidos na recalcitrância ao enraizamento em E. globulus, o presente estudo envolveu análises de parâmetros morfológicos, anatômicos e moleculares durante a rizogênese adventícia nesta espécie. A exposição à auxina exógena reverteu o fenótipo recalcitrante em E. globulus, aumentando significativamente a porcentagem de enraizamento. O câmbio vascular foi identificado como uma região de acúmulo de auxina e local de origem das raízes adventícias. Através de análises da expressão gênica em células do câmbio, observou-se que TOPLESS e IAA12, repressores da sinalização de auxina, e ARR1, envolvido na rota de sinalização de citocininas, parecem atuar como reguladores negativos do enraizamento adventício. A alta expressão destes genes em plantas controle foi significativamente diminuída com aplicação de auxina exógena. Comparativamente, em espécie de fácil enraizamento, E. grandis, a expressão destes genes se manteve em níveis mais baixos em ambas as condições de tratamento, e a concentração de ácido indol-3-acético endógeno em plantas controle mostrou-se mais elevada. Análises do padrão proteico durante o enraizamento em plantas de E. globulus tratadas ou não com auxina exógena identificaram proteínas envolvidas em diversos processos biológicos, principalmente estresse oxidativo e metabolismo energético. Diferenças interessantes foram identificadas ao comparar as diferentes condições e fases do enraizamento. Várias proteínas foram claramente relacionadas com o respectivo fenótipo apresentado pela planta em cada situação, principalmente considerando plantas controle. Os resultados aqui apresentados representam avanços relevantes no conhecimento sobre a rizogênese adventícia em plantas lenhosas, podendo ser utilizados como ferramentas no desenho de estratégias visando melhorar o enraizamento em genótipos recalcitrantes de valor para a indústria. / Eucalyptus is one of the most planted tree species in the world today, mainly due to its use as raw material for paper, cellulose and wood industries. Eucalyptus globulus and its hybrids have low lignin contents and are of great interest to industry, as this feature facilitates and reduces costs of the cellulose extraction process. However, this species is recalcitrant to adventitious rooting, making vegetative propagation by cuttings difficult. Aiming at a better understanding of the molecular mechanisms involved in rooting recalcitrance in E. globulus, this study analyzed changes in morphological, anatomical and molecular patterns during adventitious rooting in this species. Exogenous auxin exposure reversed the recalcitrant phenotype in E. globulus, significantly increasing rooting percentage. The vascular cambium was identified as a region of auxin accumulation and also the site from where adventitious roots originated. Gene expression analysis in cambium cells indicated that TOPLESS and IAA12, auxin signaling repressors, and ARR1, involved in cytokinin signaling pathway, appear to act as negative regulators of adventitious rooting. The high expression of those genes in control plants was significantly decreased by exogenous auxin treatment. Comparatively, in an easy-to-root species, E. grandis, the expression of these genes was significantlylower in both treatment conditions, and the concentration of endogenous indole- 3-acetic acid in control plants was higher. Analysis of the protein pattern during rooting in E. globulus plants treated or not with exogenous auxin allowed the identification of proteins involved in diverse biological processes, mainly oxidative stress and energy metabolism. Interesting differences were identified when comparing different rooting conditions or phases. Several proteins were clearly associated with the respective plant phenotype in each situation, particularly considering control plants. These results represent relevant advances in the knowledge about adventitious rooting in woody plants and can be used as tools in the design of strategies aiming at improving adventitious rooting in recalcitrant genotypes of industrial value.

Made available in DSpace on 2014-06-12T15:52:48Z (GMT). No. of bitstreams: 2 arquivo5096_1.pdf: 254073 bytes, checksum: 5827be40ecff661f6d409cc3b9ebfe20 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2003 / Nesse estudo, avaliamos a toxicidade pré-clínica aguda e crônica de 03 fitoterápicos, amplamente consumidos pela população brasileira para o tratamento de afecções respiratórias. A formulação dos três compostos contém mel de abelha e extrato de própolis acrescida de extrato fluído de Mikania glomerata (fitoterápico A), extrato fluído de Eucalyptus globulus (fitoterápico B) ou extratos fluídos de Zingiber officinale e Allium sativum (fitoterápico C), os fitoterápicos A e B são apresentados sob a forma de xarope e o fitoterápico C sob a forma de spray . O ensaio de toxicidade aguda dose única (7,5, 15, 25 ou 35 ml/kg; v.o.), em camundongos Swiss de ambos os sexos (n=10animais/grupo), demonstrou baixa ordem de toxicidade para os três compostos. Os fitoterápicos A e C, em doses de até 25 ml/Kg, não produziram mortalidade nos animais dos respectivos grupos, enquanto que na dose de 35 ml/kg foi verificado um percentual de 30% e 70% de mortalidade para os fitoterápico C e A, respectivamente. Em relação ao fitoterápico B, nos animais submetidos ao tratamento com doses de até 15 ml/kg, não foi verificado nenhum registro de morte. Entretanto, para as doses de 25 e 35 ml/kg foram observados mortalidade de 20% e 40%, respectivamente. Nos três estudos não foi possível determinar a DL50 dos fitoterápicos em função da impossibilidade de administração de volume superior ao volume máximo (1 ml), já utilizado na administração da dose de 35 ml/kg, permitido para a espécie estudada. Nas observações gerais, o tratamento agudo com os três fitoterápicos (7,5 e 15 ml/kg) não evidenciou nenhum indicativo de toxicidade, quando comparado ao grupo controle, do início até o 14o dia após o tratamento, para os animais sobreviventes. No estudo de toxicidade crônica em ratos de ambos os sexos, o tratamento com o fitoterápico A (7,5 ou 15 ml/kg; v.o.) não apresentou diferença no perfil hematológico e bioquímico dos grupos tratados em relação ao controle, após 90 dias de tratamento. O perfil hematológico dos grupos tratados com os fitoterápicos B ou C (7,5 ou 15 ml/kg; v.o.) também não diferiram do controle. Os animais do grupo tratado com o fitoterápico B (7,5 ml/kg), apresentaram um aumento significativo (p<0,01) na concentração plasmática de triglicérides (102,2±8.8 para machos e 100,0±8.8 mg/dl para fêmeas), em relação ao grupo controle salina (86,8±8.8 para machos e 84.6±8.8mg/dl para fêmeas). Os animais do grupo tratado com o fitoterápico C (15 ml/kg) apresentaram diferenças significantes (p<0,01) em relação à concentração plasmática de glicose (86,8±4,7 nos machos e 77,2&#1048690;4,7 mg/dl nas fêmeas), em relação aos valores do controle (66,7&#1048690;4,7 para os machos e 68,5&#1048690;4,7 mg/dl para as fêmeas). Os valores relativos à concentração de triglicérides (127,0&#1048690;11,0 nos machos e 96,0&#1048690;11,0 mg/dl nas fêmeas) também diferiram significantemente (p<0,05) em relação ao controle (86,8&#1048690;11,0 nos machos e 84,6&#1048690;11,0 mg/dl nas fêmeas). A nível clínico, estas diferenças constatadas, não parecem ser significativas, uma vez que os valores observados se encontra dentro da faixa de referência considerada normal para a espécie estudada. Após a administração crônica, o comportamento geral dos animais não apresentou alteração e a evolução do peso corporal dos grupos tratados não apresentou nenhuma diferença significante em relação ao controle. A análise macroscópica de órgãos vitais tais como pulmões, fígado, coração, rins e estômago não revelaram nenhuma alteração em relação ao grupo controle. Em relação ao peso desses órgãos, foi possível constatar que, somente nos grupos de machos tratados com o fitoterápico A foram observadas diferenças estatisticamente significativas (p<0,05) em relação ao peso do fígado e rim, para o grupo tratado com 7,5ml/kg, e do baço para o grupo tratado com 15 ml/kg. Porém, tais alterações não foram dose dependente e restringiram-se apenas aos machos. A análise desses resultados leva a conclusão que, em doses equivalentes em termos humanos, os três fitoterápicos (7,5 ou 15 ml/kg), não apresentaram efeitos tóxicos (agudo e crônico) relevantes do ponto de vista clinico, em camundongos Swiss e ratos Wistar de ambos os sexos

Memoria para optar al Título Profesional de Ingeniero de la Madera

This thesis concerns the development of semiochemical identification expertise and methodology at the University of Pretoria. The Eucalyptus snout beetle Gonipterus scutellatus was used as a model insect in developing these methods, firstly because it is a known pest in the Eucalyptus forestry industry of South Africa. Secondly, nothing is known about its chemical ecology and lastly, it is a relatively large insect that is easily worked on. Three main techniques were used namely: Electroantennography (EAG), Gas Chromatography Electroantennography Detection (GC-EAD) and Gas Chromatog- raphy Mass Spectrometry (GC-MS). EAG was used to difierentiate and identify certain Eucalyptus species that were expected to contain compounds that may function as either kairomones or allomones for G. scutellatus. The EAG process revealed that G. scutellatus responds more intensely to damaged Eucalyptus leaves as compared to undamaged leaves. The crushed foliage of the known hosts Eucalyptus globulus and E. viminalis gave larger responses than the crushed foliage from a known non-host E. citriodora. We sampled the volatiles from the crushed foliage of these three species and tentatively identified sixteen compounds from the E. globulus volatile profile that was antennally active for G. scutellatus females. The presence of these volatiles were subsequently investigated for E. viminalis and E. citriodora. The green leaf volatiles, (Z)-3 hexenyl acetate, (Z)-3-hexen-1-ol and (E)-2-hexenal and aromatic compounds, 2-phenylethanol, benzyl acetate and ethylphenylacetate often gave larger responses than the terpenes such as α-pinene, β-pinene and camphene. Crushed E. globulus leaves contained 2-phenyl ethanol, benzyl acetate, ethylphenylacetate, eucalyptol, α-pinene, (Z)-3 hexenyl acetate, (Z)-3-hexen-1-ol and (E)-2-hexenal that were antennally active. The E. viminalis profile had very little 2-phenylethanol and virtually no benzyl acetate. The E. citriodora volatile profile contained very little (Z)-3-hexen-1-ol, (E)-2-hexenal, 2-phenylethanol, benzyl acetate and ethylphenylacetate. These compounds may influence the host selection behaviour of G. scutellatusfemales. These volatiles can be tested in a behavioural bioassay in order to determine their effect on the Eucalyptus snout beetle G. scutellatus. / Dissertation (MSc)--University of Pretoria, 2010. / Chemistry / unrestricted

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第19194号 / 農博第2133号 / 新制||農||1034(附属図書館) / 学位論文||H27||N4940(農学部図書室) / 32186 / 京都大学大学院農学研究科森林科学専攻 / (主査)教授 髙野 俊幸, 教授 西尾 嘉之, 教授 梅澤 俊明 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM

Eucalyptus globulus is the subject of intense debate in California. Its invasive potential, aggressive growth, reproductive biology, and association with fire make the prediction of spread important in California. Two modeling simulations, Climex and Maxent, will illustrate the distribution and potential growth range of E. globulus in California based on climate and presence. Modeling the potential range of growth will predict invasive spread. The anticipated result is the continued spread of E. globulus in coastal regions with adequate moisture and suitable climate. Predicting the range of E. globulus in California dictates management strategy and is key for preventing further introduction, establishment, and dispersal.

Mixed-species plantations of eucalypts and acacias have the potential to improve stand productivity over that of respective monocultures through the facilitative effect of nitrogen-fixation by acacias, and increased resource capture through above- and belowground stratification. However, growth in mixed-species plantations may not be improved compared to that of monocultures when competitive interactions outweigh the effects of improved nutrient availability and resource capture. Careful selection of sites and species is therefore critical to successfully improving stand productivity using mixed-species plantations. This study set out to examine some of the processes and interactions that occur in mixed-species plantations, and the effect nutrient and water availability can have on the growth of mixtures. In three out of four mixed-species field trials examined in this study, growth was not increased in mixtures compared to monocultures. However, in the fourth field trial, heights, diameters, stand volume and aboveground biomass were higher in mixtures of E. globulus and A. mearnsii from 3-4 years after planting. The range in outcomes from mixing species in these four trials shows that a fundamental understanding of the underlying processes is required to enable a greater predictive capacity for the circumstances under which mixtures will be successful. Therefore the growth dynamics, processes and interactions were examined in the mixtures of E. globulus and A. mearnsii. The difference in productivity between mixtures and monocultures in this trial increased with time up to age 11 years, when 1:1 mixtures contained twice the aboveground biomass of E. globulus monocultures. The positive growth response of trees in mixture compared to monocultures was the result of accelerated rates of nutrient cycling, a shift in C allocation and reductions in light competition through canopy stratification. Nitrogen contents of foliage and soil clearly showed that A. mearnsii influenced the N dynamics in this trial. If these changes in N contents were due to N fixation by A. mearnsii, then about 51 and 86 kg N ha-1 yr-1 was fixed in the 1:1 mixtures and A. mearnsii monocultures, respectively. Nitrogen fixation was also examined using the natural abundance method. The delta15N values of foliage collected at 10 years were grouped according to the mycorrhizal status of the host plant. Therefore the discrimination of 15N during transfer from mycorrhizae to the host plant appeared to vary with mycorrhizal status, and the natural abundance of 15N was not used to quantify N fixation. Rates of N and P cycling in litterfall were significantly higher in stands containing at least 25% A. mearnsii (more than 31 kg N ha-1 yr-1 and more than 0.68 kg P ha-1 yr-1) compared to E. globulus monocultures (24 kg N ha-1 yr-1 and 0.45 kg P ha-1 yr-1). Rates of litter decomposition and N and P release were about twice as high in 1:1 mixtures compared to E. globulus monocultures and were even higher in A. mearnsii monocultures. It is therefore important to select N-fixing species that are capable of cycling nutrients quickly between the plant and soil, and that have readily decomposable litter. The total belowground C allocation was not significantly different between mixtures and monocultures (14 to 16 Mg C ha-1 yr-1). However, since aboveground net primary production was greater in 1:1 mixtures, the changes in nutrient availability appears to have increased total productivity (both above- and belowground), and reduced the proportion of C allocated belowground in mixtures compared to E. globulus monocultures. In a pot trial containing mixtures of E. globulus and A. mearnsii both species grew larger in mixture than in monoculture at low N levels, and mixtures were more productive than monocultures. However, at high N levels, E. globulus suppressed A. mearnsii and mixtures were less productive than E. globulus monocultures. Similar effects were found for high and low levels of P. Therefore resource availability can have a strong influence on the interactions and growth of mixtures. The productivity of mixtures may only be increased on sites where the resource for which competition is reduced in mixture is a major limiting growth resource. For example, if N is not a limiting growth factor then an increase in N availability from N-fixation may not increase growth, and the N-fixing species may compete for other resources such as soil P, moisture or light. This study has shown that mixtures containing a N-fixing trees and a non-N-fixing trees can be more productive than monocultures, but that this increase in productivity will only occur on certain sites. Examination of the growth, interactions and processes that occurred in mixtures in this study provide useful information that can aid the selection of species combinations and sites.

[Truncated abstract] Eleven sites, each with the trio of land uses: Eucalyptus globulus plantation, pasture and natural vegetation, representing from the Mediterranean climate, high rainfall region (<550 mm annually) of south-western Australia were investigated to assess medium-term changes in the P-supplying capacity of soils in eucalypt plantations growing on agricultural land. The natural vegetation soils were a benchmark for comparing soil P change since land clearing and development for agriculture. The experimental framework provided an ideal basis for studying changes in P forms since land clearing and fertilization for agriculture and the ensuing conversion to plantations (on an average 9 years ago). Conventional soil P indices measure plant available P that is more relevant to short duration annual crops and pastures. To predict medium-term P availability, P forms were determined using Hedley et al.’s (1982) fractionation scheme and fractions were grouped using the Guo and Youst (1998) criteria into readily, moderately and sparingly available P. The P species were also determined by 31P NMR spectroscopy of 0.5M NaOH-0.1M EDTA extracts. Hedley et al.’s (1982) inorganic P extracted by anion exchange resin and by NaHCO3 are widely considered to be approximations to the actual plant available P. The availability to plants of other P fractions is less certain and this is examined in an experiment to compare the plant availability of various P fractions in soils from fertilized and unfertilized land uses following exhaustive cropping in the glasshouse. The soil texture for the sites studied included coarse sand, loamy sand, clayey sand, and sandy loam. Surface soils (0-10 cm) have pH(CaCl2) in the acidic range (mean 4.4) and there is no significant difference due to differences in land use (P<0.05). The soils are of low EC (1:5 H2O) - 6 mS m-1. There is an almost 5-fold variation in organic C among sites (from 1.4% to 8%) but organic C values did not show any significant effect (P<0.05) of changes in land use. To evaluate the degree of similarity of soils within each triplet set at a site principal component analysis was carried out on those soil chemical⁄mineralogical characteristics that were least likely to be affected by changes in land use practices. This analysis showed good matching of the triplet of sub-sites on the whole, especially for the duo of pasture and plantation land uses. This degree of matching of the trio of land uses was considered while interpreting the effects of land use on the forms and behaviour of soil P, and variations due to various extents of mismatch were mostly addressed using statistical techniques including regression analysis to interpret sub-site difference

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2005. / Härtill 5 uppsatser.