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Balanced nutrition is fundamental to health and immunity. For herbivorous insects, nutrient-compositional shifts in host plants due to elevated atmospheric CO 2 concentrations and temperature may compromise this balance. Therefore, understanding their immune responses to such shifts is vital if we are to predict the outcomes of climate change for plant–herbivore–parasitoid and pathogen interactions. We tested the immune response of Paropsis atomaria Olivier (Coleoptera: Chrysomelidae) feeding on Eucalyptus tereticornis Sm. seedlings exposed to elevated CO 2 (640 μmol mol −1 ; C E ) and temperature (ambient plus 4 °C; T E ). Larvae were immune-challenged with a nylon monofilament in order to simulate parasitoid or pathogen attack without other effects of actual parasitism or pathology. The cellular ( in vivo melanisation) and humoral ( in vitro phenoloxidase PO activity) immune responses were assessed, and linked to changes in leaf chemistry. C E reduced foliar nitrogen (N) concentrations and increased C:N ratios and concentrations of total phenolics. The humoral response was reduced at C E . PO activity and haemolymph protein concentrations decreased at C E , while haemolymph protein concentrations were positively correlated with foliar N concentrations. However, the cellular response increased at C E and this was not correlated with any foliar traits. Immune parameters were not impacted by T E . Our study revealed that opposite cellular and humoral immune responses occurred as a result of plant-mediated effects at C E . In contrast, elevated temperatures within the tested range had minimal impact on immune responses. These complex interactions may alter the outcomes of parasitoid and pathogen attack in future climates. [ABSTRACT FROM AUTHOR]

Background and aims: Herbivorous insects are important nutrient cyclers that produce nutrient-rich frass. The impact of elevated atmospheric [CO] on insect-mediated nutrient cycling, and its potential interaction with precipitation and temperature, is poorly understood and rarely quantified. We tested these climatic effects on frass deposition in a nutrient-limited mature woodland. Methods: Frass deposition by leaf-chewing insects and its chemical composition was quantified monthly over the first 2 years at the Eucalyptus free-air CO enrichment experiment and contrasted with leaf nitrogen concentration, rainfall and temperature. Results: Leaf-chewing insects produced yearly between 160 and 270 kg ha of frass depositing 2 to 4 kg ha of nitrogen. Frass quantity and quality were influenced by rainfall and average maximum temperatures. In contrast, elevated CO did not impact nitrogen concentrations in fully expanded leaves and frass deposition to the woodland floor. Conclusions: Two years of elevated CO did not alter nutrient transfer by leaf-chewing insects. This may be due to the low nutrient status of this ecosystem, duration of CO fumigation or climatic conditions. However, rainfall co-occurring with seasonally higher temperatures exerted strong effects on nutrient cycling, potentially through shifts in leaf phenology with consequences for insect population dynamics and insect-mediated nutrient transfer. [ABSTRACT FROM AUTHOR]

Eucalyptus is widely cultivated in homogeneous monocultures throughout the world alongside plants of the same age. Furthermore, the productivity of forest stands is highly dependent on how solar radiation is intercepted and used. Meanwhile, it is possible to consider cultivating trees of different ages in the same area, and thus under different regimes of available solar radiation, creating a sequence of plantings and harvestings and to develop Eucalyptus-based agroforestry systems. We have examined biomass accumulation ofEucalyptus camaldulensisalong a shade gradient. Eucalyptus trees presented power-law responses to increasing irradiance for biomass, indicating it has low plasticity and is unable to maintain growth under lower irradiance levels. Biomass partitioning showed no dependence on available irradiation. Leaf density presented very little increase toward sunnier places meaning that an increment in Eucalyptus biomass would be mostly due to its increase in size and thus higher radiation interception. Careful management of shade will be a key consideration for the integration of Eucalyptus into agroforestry. With knowledge of the growth habits of different species, we will have the potential to propose more perennial ways in which to manage land and reduce anthropogenic disturbances by avoiding clear-cuts of areas that removes all plant structures. [ABSTRACT FROM AUTHOR]

The genetic divergence in 20 Eucalyptus spp. clones was evaluated by multivariate techniques based on 167RAPD markers, of which 155 were polymorphic and 12 monomorphic. The measures of genetic distances were obtained by thearithmetic complement of the coefficients of Jaccard and of Sorenso-Nei and Li and evaluated by the hierarchical methods ofSingle Linkage clustering and Unweighted Pair Group Method with Arithmetic Mean (UPGMA). Independent of the dissimilaritycoefficient, the greatest divergence was found between clones 7 and 17 and the smallest between the clones 11 and 14. Cloneclustering was little influenced by the applied procedure so that, adopting the same percentage of divergence, the UPGMAidentified two groups less for the coefficient of Sorenso-Nei and Li. The clones evidenced considerable genetic divergence,which is partly associated to the origin of the study material. The clusters formed by the UPGMA clustering algorithmassociated to the arithmetic complement of Jaccard were most consistent.

This study presents an improved theoretical formulation of the gap probability ( Pgap ) model, typically applied to indirectly estimate LAI in woody ecosystems. Specifically, we present the woody element projection function ( G W ), which characterises the angular contribution of non-leaf facets in woody ecosystems, and explain how it may be used to improve the accuracy of indirect LAI retrieval via the application of the Pgap model. G W enables separate treatment of the leaf and wood projection functions in the theoretical model, important in the typical case when Pgap includes the influence of both leaf and wood canopy elements. This study then validates the improved theoretical model using experimental data. Here, Pgap was calculated from a 3D scattering model, parameterised with highly-detailed 3D explicit tree models reconstructed from empirical data of a sampled forest stand. The experimental data was then used to quantify additional effects of view zenith angle ( VZA ), leaf angle distribution (LAD), and the influence of woody components on the indirect estimation of LAI and within-crown clumping via application of the Pgap model. Additionally, we quantify within-crown clumping of reconstructed tree models for leaf and woody elements both together and separately for the first time. LAI errors up to 25% at zenith were found when ignoring G W and were shown to be a function of VZA . Conversely, at the approximate 57.3° (1 radian) VZA , results show that there was no effect of G W due to the wood projection function converging with leaf projection functions. Within-crown clumping factors for the modelled dataset were as low as 0.35. Consequently, making a common assumption of a random distribution of canopy elements at the crown scale would lead to an LAI error of up to 65% for the 3D forest stand. We also conclude that when estimating LAI via the Pgap model, separate treatment of canopy material projection ‘ G ’ functions are required at VZA’s other than 1 radian. The findings of this study and the extended physical formulation presented here impact upon indirect Pgap LAI retrieval methods from sensors of all platforms in clumped canopy environments or canopies with woody (non-leaf) elements contributing to the extinction of light. [ABSTRACT FROM AUTHOR]

Wetland forests home to the last remaining wild populations of the helmeted honeyeater and lowland Leadbeater's possum are under threat from tree dieback and a lack of natural regeneration, putatively the result of an altered hydrological regime. To restore these critical wetland forests, a better understanding of the flooding tolerance of the seedlings of the dominant tree species, Eucalyptus camphora subsp. humeana L.A.S.Johnson & K.D.Hill, is essential. I tested the effect of flooding on the establishment and growth of E. camphora seedlings in three nursery-based experiments. These experiments involved E. camphora seedlings of different ages (1, 3, and 8 months old) being subjected to different depths and durations (up to 12 months) of flooding. Eucalyptus camphora seedlings were able to survive and grow while flooded for 12 months as long as they were emergent. However, flooding negatively affected the growth of E. camphora seedlings, with these effects increasing with increasing depth and duration of flooding, and decreasing seedling age. The ability of E. camphora seedlings to survive prolonged shallow flooding is considerable, an ability enabled by its rapid and extensive production of aerenchyma tissue and stem-borne adventitious roots under flooded conditions. Nonetheless, conditions for E. camphora seedling establishment and growth are likely to improve with reduced flooding, with an absence of flooding during its growth period (early spring-late summer) most favourable. [ABSTRACT FROM AUTHOR]

O efeito de rizobactérias promotoras do crescimento foi avaliado sobre a produção de biomassa radicular, número de miniestacas por minicepa e produtividade de minijardins clonais (número de miniestacas x porcentagem de enraizamento) de eucalipto, em viveiro. Com exceção do clone 57, em todos os demais testados foi observado incremento da biomassa radicular, com média igual a 53, 52 e 69%, respectivamente, nos clones 129, 1274 e 7074. Em geral, verificaram-se diferenças significativas em produção de miniestacas, mas não no índice de produtividade. O isolado S1 destacou-se quanto à produção de miniestacas, com incrementos que variaram de 11 a 23% para os clones 129 e 1274, respectivamente. Para o clone 7074, o incremento médio foi de 15%. Os resultados indicam claramente que rizobactérias podem ser utilizadas para maximizar a propagação vegetativa do eucalipto, por estaquia.The effect of plant growth promoting rhizobacteria was evaluated for root biomass of cuttings, number of mini-cuttings per mini-stump and productivity of mini-clonal hedges (number of mini-cuttings x rooting percent) of eucalyptus in the nursery. Except for clone 57, all other showed increase in root biomass, with an average of 53, 52 and 69% for clones 129, 1274, and 7074 respectively. In general, significant differences were found for mini-cutting production, but not for the productivity index (number of mini-cuttings x rooting percent). Isolate S1 had a substantial effect on the production of mini-cuttings, with increases varying from 11 to 23% for clones 129 and 1274 respectively. For clone 7074, the average increase was 15%. The results clearly indicated that rhizobacteria could be employed to maximize the vegetative propagation of eucalyptus by cutting.

Atualmente, a produção de mudas de Eucalyptus, em larga escala, é realizada pela miniestaquia, sob condições controladas. Todavia, ainda hoje não existe um critério técnico para determinar a idade ótima das mudas para plantio, o que pode refletir negativamente sobre a qualidade, sobretudo do sistema radicular, e, conseqüentemente, grandes perdas podem ocorrer no campo. Assim, o presente trabalho estabeleceu um critério técnico com base nas curvas de velocidade de crescimento e no intercepto entre as curvas de incremento corrente diário e incremento médio diário das variáveis altura, biomassa radicular e da parte aérea. Em virtude da restrição de volume explorável pelo sistema radicular, constataram-se reduções significativas na velocidade de crescimento das mudas que devem ser plantadas, preferencialmente, com 80 (clone A) a 100 (clone B) dias de idade, uma vez que mudas mais velhas sofrem redução na velocidade de crescimento e tendem a desenvolver problemas de malformação radicular. As implicações da baixa qualidade do sistema radicular residem na mortalidade de plantas, principalmente em períodos menos favoráveis, e na conseqüente influência na operação de replantio, bem como na realização dos testes clonais e na maior suscetibilidade das plantas aos estresses do ambiente.Presently, mass vegetative propagation of Eucalyptus is carried out by mini-cuttings, under controlled conditions. Despite the advances of this technique, there is no criterion to determine the optimum age of the cuttings for planting, which can reflect negatively on the quality, mainly on the root system, and consequently losses may occur in the field. Hence, in the present work was established a technical criteria based on the growth speed curves and intercrossing of daily current increasing curves and daily average increasing for the variables height, root, stem and shoot biomass. Due to the restriction of exploitable volume by the root system, significant reductions in the growth speed of cuttings were found, and they must be planted preferentially from 80 (clone A) to 100 (Clone B) days of age, once older cuttings undergo a reduction in the growth speed and tend to develop root malformation problems. The implications of the low quality of the root system are the mortality of plants in the field, mainly in less favorable periods, and the consequent influence on the replanting operation, as well as on the clonal tests and a greater susceptibility of plants to environment stresses.

O objetivo deste trabalho foi avaliar a decomposição e liberação de nutrientes da serapilheira foliar em um plantio de Eucalyptus grandis de primeira rotação, com 8 anos, e em rebrotas com 2 e 5 anos de idade, por meio da técnica de sacos de serapilheira. A temperatura média anual foi de 19,5 ºC e a precipitação pluvial anual, de 850 mm, com 54% das chuvas concentradas no período de outubro a dezembro. Os resultados indicaram que foi similar o porcentual de perda de massa, bem como a liberação de frações orgânicas (lignina, celulose e polifenol) e de nutrientes (N, P, K, Ca e Mg) da serapilheira foliar para o plantio de primeira rotação e as rebrotas. O porcentual de perda de massa, média dos três povoamentos, ajustou-se a um modelo quadrático (y = 99,443 + 0,0348x - 0,0003x²; R²=0,92; p=0,0225). Somente no período de maiores precipitações observou-se a efetiva perda de massa (29 - 33%), assim como a liberação de celulose (40 - 51%), de polifenóis (54 - 70%) e, em pequena quantidade, de lignina (3 - 14%). Entre os nutrientes avaliados, houve liberação de N (6 - 19%), K (49 - 60%), Ca (18 - 20%) e Mg (27 - 39%), enquanto o P foi acumulado (-20 e -40%). Na região norte fluminense, a dinâmica da decomposição e liberação de nutrientes da serapilheira foliar de eucalipto, durante 382 dias, evidenciou a liberação de K > Mg > Ca > N e a imobilização de P, sendo marcadamente influenciada pela precipitação pluvial.This work aimed to evaluate the decomposition and nutrient release of leaf litter in 8-year old Eucalyptus grandis first rotation and 2 and 5-year old regrowth systems through litter bag technique. The annual average temperature was 19.5 ºC and annual rainfall was 848 mm, with 54% of rains concentrated in the period from October to December. The results showed that the dry weight loss, nutrient release (N, K, Ca and Mg) and organic fraction release (lignin, cellulose and polyphenols) were similar for the first rotation and regrowth systems. The mass loss percentage, mean of three sites, fitted a quadratic model (y = 99.443 + 0.0348x - 0.0003x²; R²=0.92; p=0.0225). Only in the rainfall period, effective mass loss (29 - 33%), cellulose release (40 - 51%), polyphenols (54 - 74%) and low lignin release (3 - 14%) was observed. Among the nutrients, release of N (6 - 19%), K (49 -60%), Ca (18 - 20%), Mg (39 - 27 %) and immobilization of P (-20 and -40%) was observed. In northern Rio de Janeiro State, the eucalypt leaf litter decomposition dynamics showed release of K > Mg > Ca > N , over 382 days, and immobilization of P, markedly influenced by rainfall.

O objetivo deste estudo foi determinar o regime de manejo mais rentável, dentre as variações de idade e intensidades de desbaste, índice de local, taxas de juros, preços de madeira e idades de corte final. Para tanto, utilizaram-se dados de um experimento de desbaste instalado na Empresa Copener Florestal Ltda., Bahia. O sistema de prognose empregado foi desenvolvido por Clutter (1963). O método de avaliação financeira utilizado foi o Benefício Periódico Equivalente (BPE). Os resultados indicaram que o regime com desbaste foi mais rentável economicamente, comparado ao regime sem desbaste. No entanto, à medida que aumentou a intensidade de desbaste, os valores de BPE tenderam a diminuir. Pôde-se observar, também, que menores taxas de juros e maiores índices de local tenderam a aumentar a rentabilidade dos regimes. O regime que proporcionou maior rentabilidade foi o do desbaste realizado aos 4 anos e o corte final aos 9 anos. Não houve influência significativa das variáveis índice de local, taxa de juros e custo de implantação, na determinação do regime mais rentável, ou seja, o regime mais rentável permaneceu sendo do desbaste aos 4 e corte final aos 9 anos. No entanto, a variável preço da madeira do desbaste influenciou a determinação do regime mais rentável, e o aumento no preço de acordo com a idade de colheita resultou em desbaste aos 6 anos e o corte final aos 9 anos, como o regime mais rentável. Da mesma forma, a elevação no preço da madeira do corte final, de acordo com a idade de corte, resultou em desbaste aos 4 anos e corte final aos 12 anos, como o regime mais rentável. A simulação de elevação no preço da madeira do desbaste e do corte final, simultaneamente ao mesmo tempo, gerou como regime de manejo mais rentável o desbaste aos 6 anos e o corte final aos 12 anos. Concluiu-se que houve influência direta das variáveis preço da madeira do desbaste e do corte final na determinação do regime mais rentável.The objective of this work was to determine the most profitable management method, among the variation of age and thinning intensities, site index, interest rates, wood prices and last cutting age. To achieve this goal, data of a thinning experiment established at Empresa Copener Florestal Ltda, Bahia, were used. The prediction system used was developed by Clutter (1963). The economic evaluation method used was the Equivalent Periodic Benefit (BPE). The results showed that the method with thinning was economically better than the method without thinning, but as the thinning intensity increased the BPE values tended to decrease. Also, lower interest rates and higher site indexes were observed to increase the method profits. The method that provided the greatest profit was obtained with thinning at four and last cut at nine years of age. The variables site index, interest rate and establishment cost did not significantly influence the determination of the most profitable method, that is, the most profitable method remained the thinning at four and last cut at nine years of age. On the other hand, the variable thinned wood price influenced the determination of the most profitable method. The increase in price according to the harvesting age resulted in thinning at six and last cut at nine years of age as the most profitable method. Similarly, the increase in wood price of the last cut according to the cutting age resulted in thinning at four and last cut at 12 years of age as the most profitable method. The simulation of increasing the price of thinned and last cut wood, at the same time, generated as the most profitable method thinning at six and last cut at 12 years of age. It was concluded that there was a direct influence of variables prices of thinned and last cut wood on the determination of the most profitable method.

In this study the effect of resin content and press time of particleboard from Date palm residues, Eucalyptus camaldulensis, Tamarix residues and prosopis (Mesquite) producted were investigated in southern of Iran.Variable factors as resin content (9, 10 and 11 percent) and press time (5, 6 and 7 minutes) and total of 27 boards were fabricated. Other factors such as type of resin (UF), hardener content (2 percent) type of hardener (NH4Cl) press closing time (4.5 mm/sec.), board density (0.7 gr/cm3) press pressure (30 kg/cm2) and press temperature (160 °C)were held constant.All boards were tested according to DIN-68763 standard. The factorial experimental design at completely random test was used. The results of this study could be summarized as follows:Increasing the resin content from 9 to 11 percent, MOE and IE and decreased thickness swelling after two and 24 hours immersion in water. The results revealed that the polymerization of resin and wood is better at 11 percentresincontentand6 minutes of press time.

A biologia de Mimallo amilia Cramer (Lepidoptera: Mimallonidae) foi estudada em folhas de Eucalyptus urophylla em laboratório a 25 ± 2 ºC, 60 ± 10% de umidade relativa e fotoperíodo de 12 horas de luz e 12 horas de escuro. Essa espécie teve duração da fase larval de 34,88 dias e cinco estádios larvais. Houve mortalidade de lagartas no primeiro, terceiro e quarto estádios com 5,00; 7,89; e 14,28%, respectivamente. Os períodos de pré-pupa e de pupa foram de 4,33 ± 0,33 e 3,90 ± 0,23 e de 18,78 ± 0,69 e 18,82 ± 0,41 dias para machos e fêmeas, respectivamente. Cada fêmea de M. amilia depositou 4,86 ± 0,48 posturas com 19,84 ± 1,76 ovos por postura. O período de incubação dos ovos foi de 8,60 ± 0,24 dias, com viabilidade de 88,63%. A longevidade de adultos foi de 5,66 ± 0,61 e 9,22 ± 0,79 dias, com envergadura das asas de 42,70 ± 0,32 e 49,70 ± 0,17 mm para machos e fêmeas, respectivamente, e razão sexual de 0,56. As lagartas dessa espécie apresentaram tamanho de 0,90 ± 0,01 mm no primeiro estádio a 4,40 ± 1,42 mm no último.The biology of Mimallo amilia Cramer (Lepidoptera: Mimallonidae) was studied on Eucalyptus urophylla leaves in laboratory conditions (25 ± 2ºC, 60 ± 10% relative humidity and 12L:12D photoperiod). This species showed 33.88 day for the larval stage with five larval instars. Larval mortality occurred during first, third and fourth instars with 5.00, 7.89 and 14.28%, respectively. Pre-pupa and pupa stages lasted 4.33 ± 0.33 and 3.90 ± 0.23, and 18.78 ± 0.69 and 18.82 ± 0.41 days for males and females, respectively. Each female laid 4.86 ± 0.48 egg masses with 19.84 ± 1.76 eggs per egg mass. Incubation period lasted 8.60 ± 0.24 days with 88.63%. egg viability. Adult longevity was 5.66 ± 0.61 and 9.22 ± 0.79 days with adult wingspan of 42.70 ± 0.32 and 49.70 ± 0.17 mm for males and females, respectively, with 0.56 sex ratio. Length of this species' caterpillars was 0.90 ± 0.01 mm at the first instar and 4.40 ± 1.42 mm at the last instar.

Foi observada a ocorrência da coleobroca Sphallenum tuberosum Bates, 1870 (Coleoptera: Cerambycidae) atacando árvores de Eucalyptus cloesiana e Eucalyptus grandis no Município de Prado, Estado da Bahia, em setembro de 2002. As árvores atacadas, saudáveis ou decadentes, apresentavam troncos envoltos por cipós da família Malpighiaceae, gênero Stigmaphyllon, que serviam de suporte para penetração da broca no tronco do eucalipto. As galerias formadas por larvas de S. tuberosum apresentavam direção descendente.The woodborer Sphallenum tuberosum Bates, 1870 (Coleoptera: Cerambycidae) was found damaging Eucalyptus cloesiana and Eucalyptus grandis trees in the Municipality of Prado, State of Bahia, Brazil in September 2002. Damaged trees, either healthy or decadent, had liana of the genus Stigmaphyllon (Malpighiaceae) envolving their trunks which represents a support for the woodborer larvae to penetrate into trunks of eucalyptus forming downward galleries.

O principal objetivo deste estudo foi avaliar as estimativas geradas por um modelo de distribuição diamétrica, do ponto de vista biológico. Também foi objetivo avaliar a eficiência do método dos ingressos porcentuais para determinação da idade técnica do primeiro e do segundo desbaste em plantação de eucalipto. A análise qualitativa do modelo consistiu em avaliar os resultados obtidos pelo método dos ingressos porcentuais, o comportamento das distribuições diamétricas projetadas para idades futuras e o comportamento das distribuições diamétricas remanescentes, após algumas simulações de desbaste, do ponto de vista da teoria, da lógica e do realismo biológico. Pôde-se inferir que o modelo de distribuição diamétrica proposto é biologicamente correto e consistente. A estagnação do crescimento é mais rápida após o desbaste. Concluiu-se, ainda, que o método dos ingressos porcentuais é adequado para determinar a idade técnica do primeiro e do segundo desbaste. O modelo avaliado permite simular diferentes cenários, gerando estimativas consistentes, podendo ser aplicado sem restrições, ou seja, podem ser simulados cenários que contemplem, ou não, as condições observadas no campo.The main objective of this study was to evaluate the estimates generated by a diametric distribution model, under the biologic point of view. Another objective was to evaluate the efficiency of the percentage of entries method to determine the technical age for the first and second thinning in eucalypt stands. The qualitative evaluation of the model was carried out through the evaluation of the results obtained by the percentage of entries method, the behavior of the diametric distributions projected for the future, and the behavior of the remaining distributions after some thinning simulations, theoretically, logically and biologically speaking. According to the results it was concluded that the diametric distribution model proposed is biologically correct and consistent. Growth stagnation is stimulated after thinning. It also was concluded that the percentage of entries method is suitable to determine the technical age for the first and second thinning. The model evaluated allows the simulation of various situations, generating consistent estimates and it can be used without restrictions, that is, situations can be simulated with or without the conditions observed in the field.

Este trabalho foi realizado com o objetivo de especificar um modelo de crescimento e produção, em que a produção volumétrica é função da área basal por hectare e da altura média de plantios de eucalipto. Para isso, foram utilizados dados de parcelas permanentes, localizadas na Bahia, com idades entre 28 e 89 meses. Após as análises, verificou-se que o modelo proposto forneceu estimativas volumétricas mais precisas do que o modelo de Clutter (1963) para povoamentos jovens, independentemente da classe de produtividade. No entanto, o modelo proposto forneceu estimativas volumétricas menos precisas nas idades técnicas de colheita (ITC), na menor e maior classes de produtividade.The objective of this work was to specify a growth and yield model in that volumetric yield is a function of the basal area per hectare and mean height of the eucalyptus plantations. Thus, data of permanent plots located in the state of Bahia-Brazil were used, with ages ranging from 28 to 89 months. After analysis, it was verified that the proposed model provided more precise volumetric estimates than the Clutter model (1963) for young plantations, independently of the productivity class. However, the proposed model provided less precise volumetric estimates in the technical cut age (ITC) for smaller and larger productivity classes.

Antes da recomendação em larga escala de biossólido em plantações florestais, é preciso compreender seus efeitos no solo e na planta. Assim, a fertilidade do solo, o estado nutricional e o crescimento de um povoamento de Eucalyptus grandis fertilizado com biossólido foram avaliados em um experimento na Estação Experimental de Ciências Florestais de Itatinga (SP), ESALQ/USP. O delineamento experimental foi o de blocos casualizados, com quatro blocos e nove tratamentos: (1) Testemunha; (2) Adubação mineral; (3) 5 t ha-1 de bios. + K; (4) 10 t ha-1 de bios. + K; (5) 10 t ha-1 de bios.; (6) 10 t ha-1 de bios. + K + P; (7) 15 t ha-1 de bios. + K; (8) 20 t ha-1 de bios. + K, e (9) 40 t ha-1 de bios. + K. Foram analisadas quimicamente amostras de solo (camadas de 0-5, 5-10 e 10-20 cm) e de folhas. A produção de madeira foi avaliada por meio da colheita e pesagem de árvores. Até 32 meses após a aplicação do biossólido, 36 meses pós-plantio, constataram-se aumentos do pH, dos teores de C orgânico, de P-resina e de Ca trocável nas três camadas, diretamente associados às doses de biossólido aplicadas. Os teores de S-SO4(2-) e K trocável diminuíram 13 meses após a aplicação do biossólido e, 19 meses depois, os teores estavam aumentados. O Al trocável diminuiu com o aumento das doses de biossólido, nas três camadas amostradas. A aplicação de biossólido influiu positivamente na nutrição das plantas, proporcionando uma produção de madeira igual à obtida no tratamento que só recebeu adubação mineral (1,5 t ha-1 de calcário dolomítico e, em kg ha-1, 98 de N, 79,5 de P2O5, 165 de K2O, 1,3 de B e 1,2 de Zn), quando a dose de biossólido foi equivalente a 12 t ha-1.Before recommending biosolids at large scale for forest plantations it is necessary to have an ample understanding of its effects on soil and plant. Thus, it was evaluated the soil fertility, nutritional status and growth of a Eucalyptus grandis plantation fertilized with biosolid (bios). The trial was established at the Experimental Station of Forest Sciences of Itatinga - ESALQ/USP (São Paulo State, Brazil). The experimental design was in complete randomized blocks, with 4 replicates. There were nine treatments, namely: (1) control; (2) mineral fertilization; (3) 5 t ha-1 bios + K; (4) 10 t ha-1 bios + K; (5) 10 t ha-1 bios; (6) 10 t ha-1 bios + K + P; (7) 15 t ha-1 bios + K; (8) 20 t ha-1 bios + K; and (9) 40 t ha-1 bios + K. Soil samples (layers 0-5, 5-10, and 10-20 cm) and leaves were chemically analyzed. The stem wood production was evaluated at harvest by weighing the trees. The pH, soil organic carbon, resin-P, and exchangeable Ca increased in the three soil layers up to 32 months after the biosolid application (36 months after planting) in direct association with the increasing biosolid rates. The S-SO4(2-) and exchangeable K decreased 13 months after the biosolid application and increased again 19 months later. The exchangeable Al in the three sampled soil layers decreased as biosolid dose was increased. The application of 12 t ha-1 of biosolid had a positive influence on plant nutrition and led to a wood yield equivalent to the mineral fertilization treatment (1.5 t ha-1 lime, and in kg ha-1, 98 N, 79.5 P2O5, 165 K2O, 1.3 B, and 1.2 Zn).

O Serviço Nacional de Malária operacionalizou uma fábrica de pesticidas organoclorados utilizados em campanhas de saúde pública (HCH e DDT) entre 1950 e 1965, na Cidade dos Meninos, no município de Duque de Caxias, RJ, visando combater doenças rurais endêmicas. Após denúncia na mídia, em 1989, a FEEMA detectou que, com a desativação da fábrica, foram deixados resíduos da produção dos pesticidas, causando a contaminação do solo. Neste trabalho foram realizadas análises foliares e de solo em dois talhões de espécies de eucalipto (Eucalyptus grandis e Corymbia citriodora (Hook.) K.D. Hill & L.A.S. Jhonson), com o objetivo de avaliar o potencial da espécie como fitorremediador de área contaminada por organoclorados. Coletaram-se cinco amostras compostas de folhas (três do C. citriodora e duas do E. grandis) e uma composta de solo em cada um dos talhões estudados para análise de organoclorados por cromatografia gasosa. As alturas médias dos talhões de E. grandis e C. citriodora foram, respectivamente, de 9,1 e 16,8 com diâmetros médios de 7,8 e 15,95 cm; a média de C. citriodora foi similar à de outros plantios em regiões de mata atlântica, ficando a de E. grandis pouco abaixo. Detectou-se a presença de organoclorados nas folhas analisadas, porém em baixas concentrações. Nos solos, as concentrações encontradas foram altas, sendo maiores no talhão de E. grandis. Os resultados foram comparados com análises prévias na área, indicando que as espécies atuaram como fitorremediadoras, especialmente o C. citriodora, uma vez que houve redução na contaminação do solo e absorção dos organoclorados pelas folhas.The Malaria National Service built a factory of organoclorine pesticides used in public health campaigns (HCH and DDT) between 1950 and 1965, at Cidade dos Meninos, in the municipal district of Duque de Caxias/RJ to control the dissemination of endemic rural diseases. After a media outcry, in 1989, FEEMA investigated and found out that after the factory closure piles of residues were left behind causing the contamination of the soils. Analyses of foliar tissues and soil were conducted in two stands of Eucalyptus (Eucalyptus grandis e Corymbia citriodora (Hook.) K.D. Hill & L.A.S. Jhonson), with the objective of evaluating the potential of the species as phytoremediator of contaminated soils by organochlorines pesticides. A composite soil sample and five samples of leaves were collected in each one of the studied places. Three leaf samples from C. citriodora and two from E. grandis were analized for pesticides organochlorines by gas chromatography. Both species grew on the same conditions, with average heights of 9,1 e 16,8 m and average diameters of 7,8 and 15,95 cm for E. grandis and C. citriodora, respectively. The average height and diameter of C. citriodora were similar to those found for other stands in the Atlantic forest region while the E. grandis was a little bellow those averages. The presence of organochlorine pesticides was detected in the leaves at low concentrations but the concentrations in the soils were high, being greater in the E. grandis plantation. These results were compared to previous analyses and suggested that the species can function as phytoremediators especially the C. citriodora.

Foi feita uma análise temporal da curva de enraizamento de dois clones híbridos de eucalipto (C1 - E. grandis x E. urophylla; C2 - E. grandis x E. saligna), visando determinar o tempo ótimo de permanência dos propágulos vegetativos na casa de enraizamento, sob o ponto de vista técnico e do risco de incidência de doenças. Constatou-se que o tempo ótimo necessário para induzir a rizogênese depende do clone de eucalipto e que o conhecimento do modelo temporal pode fornecer subsídios ao gerenciamento de viveiros florestais. Além disso, foram estabelecidos dois critérios úteis para determinar o tempo ótimo de indução do enraizamento, sendo estes o intercepto da curva de incremento corrente diário (ICD) e incremento médio diário (IMD) e o tempo em que ocorre o máximo valor da velocidade de enraizamento. Para os clones 1 e 2, pelo critério do intercepto das curvas de ICD e IMD, 20 e 30 dias foram definidos como tempo ótimo, enquanto pelo critério de máxima velocidade de enraizamento os valores foram de 15 e 22 dias, respectivamente, sendo este último critério o mais indicado, levando-se em consideração o custo das instalações e o risco de incidência de doenças na propagação clonal do eucalipto.A temporal analysis of the rooting curve of two hybrid clones of eucalypt (C1 - E. grandis x E. urophylla; C2 - E. grandis x E. saligna) was carried out to determine the optimum time for permanence of the vegetative propagules in the rooting house, considered under the technical viewpoint and risk of disease incidence. It was found out that the optimum time needed to induce rhyzogenesis depended on the Eucalyptus clone and that a knowledge of temporal model may provide a basis for the management of forest nurseries. Besides, two useful criteria were established to determine the optimum time to induce rooting, i.e., the intercept of the daily current increase curve (DCI) and daily average increase (DAI) and the time during which the maximum rooting velocity value occurs. For clones 1 and 2, respectively, 20 and 30 days were defined as optimum times, based on the criterium of the intercept of the DCI and DAI curves, while15 and 22 days were defined as optimum times, based on the maximum rooting velocity criterium, with the latter criterium being the most indicated, taking into account installation cost and risk of incidence of diseases in eucalyptus clonal propagation.

In this study, the breeding perspectives of 41 open-pollinated progenies of Eucalyptus grandis were evaluated based on their wood traits. The progenies were distributed in two experiments in a randomized complete block design, with three replicates and linear plots containing six plants each. The traits were assessed at eight years of age. Two trees from each plot were selected for this assessment based on better growth, stem form and phytosanity. Significant differences in basic density, sapwood/heartwood ratio, bowing, specific gravity, parallel compression and static bending were detected among the progenies. These traits were potentially promising for breeding programs, with heritability coefficients that varied from 0.34 to 0.61 on a progeny mean basis. There was no genetic variation in the moisture content, board end-splitting, log volume under bark, log eccentricity, bark content, crooking, and shear strength of the progenies. Intermediate to highly significant genetic correlations were detected among the physical and mechanical properties, as well as between pairs of traits such as basic density and log end-splitting, basic density and bowing, specific gravity and bowing, sapwood/heartwood ratio and bowing, log volume and bowing, and log volume and log end-splitting. These results show that the levels of growth stress in trees can be reduced by selection using indirect traits such as the sapwood/heartwood ratio and bowing.

Estudou-se a atividade florestal no município de Viçosa-MG, a partir de questionário aplicado aos agricultores cujas propriedades rurais possuíam florestas plantadas. Foi amostrado um total de 63 propriedades rurais, abrangendo uma área de 2.096,95 ha. As áreas de floresta nativa e plantada, na amostra, foram de 372,00 e 260,17 ha, o que corresponde, respectivamente, a 17,74 e 12,41% da área amostrada. O tipo de floresta nativa predominante foi a capoeira (67,55%), e a espécie preferida para o reflorestamento foi o eucalipto (92,68%). O uso médio da mão-de-obra nas fases de implantação, manutenção e colheita dos plantios florestais foi estimado em 30,21, 13,64 e 61,25 dias-homem/ha, respectivamente, totalizando 105,10 dias-homem/ha, sendo a participação da mão-de-obra familiar de 25,24%. Os custos inerentes à atividade florestal foram estimados em R$419,30/ha para implantação; R$146,49/ha e R$80,34/ha para manutenção no primeiro e segundo ano, respectivamente; e R$2,11/m³ para colheita da madeira. Os plantios florestais concentram-se nas áreas de encostas, e o número médio de empregos gerados pelo reflorestamento (eucalipto) foi 0,042 emprego/ha. Concluiu-se, de modo geral, que o reflorestamento é considerado atividade pouco atrativa, não identificando propriedades tipicamente florestais, sendo recomendada a elaboração de políticas públicas de incentivo ao reflorestamento.Forest activity was studied in Viçosa-MG, through a questionnaire applied to farmers who planted forests. A total of 63 farms were sampled, comprising an area of 2,096.95 ha. The natural and planted forest areas sampled were of 372.00 ha and 260.17 ha, corresponding to 17.74% and 12.41%, respectively. The predominant natural forest was the secondary forest (capoeira) (67.55%), and the species chosen for reforestation was eucalypt (92.68%). Average labor use in the phases of implementation, maintenance and harvest of the forest plantations was estimated at 30.21, 13.64 and 61.25 days-man/hectare, respectively, totalling 105.10 days-man/hectare, with family labor participation of 25.24%. Forest activity costs (R$/ha) were estimated at R$419.30 for implementation; R$146.49 and R$80.34 for first and second year maintenance, respectively, and R$2.11/m³ for wood harvesting cost. The forest plantations are concentrated at the hillside areas and the average number of jobs generated by reforestation (eucalypt) was 0.042 jobs/hectare. It was concluded that, overall, reforestation was considered a rather unattractive activity, with typical forest properties remaining unidentified. Thus, it is recommended the elaboration of public policies to encourage reforestation.

Este experimento foi instalado com o objetivo de estudar os parâmetros morfológicos nas avaliações da qualidade de mudas de Eucalyptus grandis produzidas em diferentes tamanhos de tubetes. O substrato utilizado foi uma mistura de 80% de composto orgânico (CO) e de 20% de moinha de carvão (MC), adubados com a presença e ausência dos elementos N, P e K. Como embalagens foram utilizados quatro tamanhos de tubetes de plástico rígido, com volumes de 50, 110, 200 e 280 cm³. A adoção da altura e da relação altura/peso de matéria seca da parte aérea deve ser considerada, por terem sido estes os parâmetros que apresentaram boa contribuição relativa à qualidade das mudas, sem contudo ser um processo destrutivo. A adoção somente da altura para estimar a qualidade de mudas, aos 90 dias de idade no tubete de 110 cm³ de volume, poderá ser utilizada por apresentar boa contribuição relativa e por ser um parâmetro de fácil determinação e não ser um método destrutivo, além de sua medição ser muito fácil.An experiment was carried out to study the morphological parameters used to evaluate the quality of Eucalyptus grandis seedlings producedin different tube sizes. A mixture of 80% organic compound (CO) and 20% charcoal powder fertilized with and without N, P and K was used as substrate. Four sizes of hard plastic tubes at the volumes of 50, 110, 200 and 280 cm³ were used as packaging. Height and height/weight relationship of the aerial part dry matter should be considered, since although providing a satisfactory contribution to seedling quality pattern, the parameters did not present a destructive process. The use of height only to estimate the quality of Eucalyptus grandis seedlings in the 110 cm³ volume tube when they were 90-day old should be used, since it presents a satisfactory relative contribution, besides being a nondestructive, easily determined and measured parameter.

Forest tree hybrid zones provide a wealth of novel genetic variation that can be harnessed to safeguard populations in changing climates. In the past 30 years, natural and artificial forest hybrid zones have facilitated significant contributions to selective breeding programs, conservation, and our understanding of the evolutionary processes and mechanisms that influence the maintenance of species and community interactions. This review highlights advances in these areas using forest hybrid zones. Taking examples from well-known genera, including eucalypt, poplar, oak and spruce, this review details the important role hybrid zones play in managing conservation of genetic variation, the environmental and non-environmental factors that influence barriers to reproduction, and the impact that genetic ancestry may have on community biodiversity. Given increasing concern surrounding species adaptability under rapidly changing conditions, we describe how the study of forest hybrid zones, using quantitative and genomic approaches, can facilitate conservation of genetic diversity and long-term species management.

• Wildfires (WF) frequency has increased along of the years in Mediterranean region. • WF runoff may comprise dangerous impacts to freshwater ecosystems. • Ashes exposure caused growth rate (GR) inhibition and changes at biochemical level. • The larger GR inhibition was observed to Lemna exposed to high severity WF ashes. • Eucalypt ashes showed be more toxic to the macrophytes, than the pine ashes. Wildfires are a social and environmental concern to the world due to their many adverse effects, including risk to the public health and security, economic damages in prevention and fight, ecosystems pollution, land usage sustainability, and biodiversity. In the Mediterranean region, these events have increased in the last years. Although several studies evaluated the impacts of the wildfires on the structure and function of the ecosystems and their communities, there is a lack of information at the biochemical level beyond the toxicological effects to the organisms. So, aiming to evaluate the potential toxic and biochemical effects of pine and eucalypt ash from high and low severity burned areas in the aquatic environments, L. minor growth, fatty acid and carbohydrate profiles were studied. Data showed that the wildfires ash from high severity burned areas are more toxic, with a higher growth inhibition than when exposed to ash from low severity burned areas. Considering the ash from low severity burned areas, eucalypt ash revealed to be more noxious to the macrophyte than pine ash. Furthermore, it was observed a decrease in the diversity and abundance of fatty acids content, comparing with the control. An opposite trend was observed in carbohydrates which increased with the organisms' exposure to almost all ash types, except in case of the organisms exposed to eucalypt ash from high severity burned areas, where carbohydrate content decreased. [ABSTRACT FROM AUTHOR]

• Soil seed banks of wet temperate forests provide a storage effect. • Fire-cued germination concentrated in ant-dispersed species. • Germination of shade-tolerant species not enhanced by fire cues. • Edaphic variability and structural complexity promote plant diversity. • Practices that generate heterogenous environments will benefit biodiversity. Our understanding of how environmental heterogeneity shapes plant community dynamics is largely based on above-ground diversity despite the importance of seed banks as reservoirs of genetic and taxonomic diversity that buffer plant populations and influence vegetation following disturbance. Using a plant functional trait approach, this study examined the importance of fire-related germination cues and environmental determinants of plant community turnover in wet forests of south-eastern Australia – forests of both high conservation value and the focus of current timber harvesting. We surveyed extant vegetation, soil seed banks, forest structure and edaphic properties across 62 sites burnt in 1939 and not subsequently affected by wildfire or logging. A total of 46 families, and 99 species were identified in extant vegetation with 43 and 126 respectively in the soil seed bank, with only 32% of species co-occurring in both species' pools. Despite historically long fire return intervals, the soil seed bank demonstrated a clear positive response to fire-related germination cues (heat in combination with smoke) that were concentrated in hard-seeded species dispersed by ants. Seeds from early successional species showed no response to fire cues, while species typical of the wetter margins of these forests were killed by high heat. The soil seed bank was dominated by species associated with early successional stages, consistent with the initial floristics model of succession. Woody species were largely restricted to extant vegetation and replacement is most likely to occur from future seed rain. Spatially structured environmental heterogeneity shaped plant turnover with the relative strength of environmental controls differing among functional types and pools of diversity. Differential response of the combined species pool relative to extant vegetation demonstrates that the soil seed bank provides a storage effect. Forest management practices that generate patchy and heterogenous environments, including the intensity of regeneration burns and density of overstorey species, will benefit biodiversity conservation through overstorey structural controls on resource availability and diversity of understorey vegetation, that is transferred to soil seed banks via tight abiotic controls and seed inputs. [ABSTRACT FROM AUTHOR]

El tamaño de una población y sus variaciones en el tiempo y espacio son variables importantes que permiten determinar el funcionamiento de una comunidad de insectos en el campo. De esta manera, con el uso de trampas etanólicas de intercepción, fue estudiada la fluctuación poblacional de Scolytidae en plantaciones de Eucalyptus grandis. El estudio fue realizado por un período de dos años en la región de Antonio Dias, Minas Gerais, Brasil, donde los insectos fueron recolectados y analizados en función de la temperatura y precipitación. Fueron recolectadas 16 especies de la familia Scolytidae, con predominancia de Xyleborus paraguayensis, Xyleborus affinis y Xyleborus ferrugineus, las cuales representaron el 96.27 % del total de individuos capturados. La temperatura y precipitación fueron las variables que influenciaron directamente en la fluctuación poblacional de estos insecto. Las dos primeras especies presentaron mayores poblaciones durante la época seca, mientras que X. ferrugineus presentó mayor número de individuos en los meses con mayor precipitación.The size of a population and its variations through time and space are important variables that can be used to determine insect community structure in the field. For this reason ethanolic traps were used to study population fluctuation of Scolytidae species in plantations of Eucalyptus grandis. This study was developed during two years in Antônio Dias, State of Minas Gerais, Brazil where these insects were collected and analyzed in function of temperature and rainfall. Out of 16 Scolytidae species collected those with higher number of individuals were Xyleborus paraguayensis, Xyleborus affinis and Xyleborus ferrugineus (96.27 % of individuals). Temperature and rainfall affected numbers of these insects collected with ethanolic traps. The first two species presented larger populations during periods of low rainfall while X. ferrugineus presented the opposite pattern.

O objetivo deste trabalho foi estudar os efeitos dos períodos de convivência e de controle de Brachiaria decumbens sobre o desenvolvimento inicial de clones de Eucalyptus grandis x Eucalyptus urophylla. Para isso, um ensaio foi conduzido, no município de Três Lagoas-MS, no período de janeiro a dezembro de 1997. Os tratamentos experimentais consistiram de diferentes épocas e períodos de convivência das plantas daninhas na cultura do eucalipto. As épocas foram divididas em dois grupos. No primeiro, a convivência se iniciava no transplante das mudas e era estendida até 28, 56, 84, 112, 140, 168, 224, 252 e 364 dias após. No segundo grupo, a convivência se iniciava aos 0, 28, 56, 84, 112, 140, 168, 224 e 252 dias após o transplante e era estendida até o final de um ano. As principais plantas daninhas que ocorreram na área experimental foram Brachiaria decumbens e Spermacocea latifola. As plantas jovens de eucalipto foram bastante suscetíveis à interferência das plantas daninhas, apresentando um período anterior à interferência inferior a 14-28 dias. Para assegurar o desenvolvimento da cultura, o período total de prevenção à interferência foi de 140 dias, e o período crítico de prevenção à interferência, de 14-28 a 140 dias após o transplante, considerando o índice de 5% de redução em diâmetro.A field trial was carried out in Três Lagoas-MS, Brazil, from January to December of 1997, to study the effects of control and coexistence period of Brachiaria decumbens on the growth of Eucalyptus grandis x Eucalyptus urophylla clones. The experimental design was a complete randomized block design, with four replications. The treatments consisted of different periods of weed-eucalypt association. The periods were divided in two groups. In the first one, the weed-eucalypt coexistence initiated during the eucalypt transplanting, continuing up to 28, 56, 112, 140, 168, 224, 252 and 364 days after it. In the second group, the weed coexistence began at 0, 28, 56, 112, 140, 168, 224 and 252 days after the transplanting and ended 364 days later. The main infesting weeds were Brachiaria decumbens and Spermacocea latifola. The young eucalypt plants were very susceptible to weed interference. To assure normal crop development it was necessary to maintain a weed free period of 140 days after transplanting.

This study aimed at the fractionation of lignin by a simple acid precipitation from hardwood and softwood Kraft black liquors to propose new value-added applications. The precipitation was made sequentially by acidification at five different pHs (9, 7, 5, 3 and 1). The different lignin fractions were analyzed in terms of yield, ash content, elemental analysis, thermal analysis, FTIR, 1 H NMR and GPC. Hardwood lignins showed distinct relative molecular mass distributions, while softwood lignins showed similar relative molecular mass distributions in the three fractions obtained at higher pHs (pH 9, 7 and 5). This simple acid precipitation was shown to be an effective method to obtain relatively high yields of lignin. Molecular characterization by FTIR (carbonyl band) indicated that hardwood lignin was most oxidized mainly in the low pH fractions (5, 3 and 1), while the softwood lignin only presented discrete oxidized products in the lowest pHs (3 and 1). Interestingly, precipitation at pH 3 produced ash-free hardwood and softwood lignin fractions, which is a valuable product for the development of better end uses. [ABSTRACT FROM AUTHOR]

The effect of pulp pretreatment with hot acid hydrolysis on high consistency ozone bleaching was evaluated. An experimental plan was set up involving the full optimization of the A-stage and its application in Elemental Chlorine Free–ECF–[A/(aZe)DP and A(aZe)DP] and Total Chlorine Free–TCF–[A/(aZe)(EP)P and A(aZe)(EP)P] sequences for eucalypt kraft pulp bleaching. The A-stage removed a significant amount of lignin and HexA from the pulp, and the subsequent Z-stage remained efficient after completion of the A-stage. The chemical savings caused by the A-stage were significant (∼7 kg ClO2/adt). The optimum conditions for the A-stage were pH 3.0, 90°C for 120 min, and 10% consistency. The strength properties of pulps bleached with the (aZe)DP (reference) and A/(aZe)DP ECF sequences were similar, but the TCF sequence A/(aZe)(EP)P delivered slightly lower strength properties than the ECF sequences. Fiber peeling studies indicated that the HexA present in the kraft pulp is not concentrated on the fiber surface, as previously thought. [ABSTRACT FROM AUTHOR]

Browsing cascades have strong implications for biodiversity conservation and fire management. The associational resistance and associational susceptibility hypotheses suggest different mechanisms. We tested the veracity of these two hypotheses by using small dry eucalypt forest and woodland trees. At 67 sites, we measured the height of the browse line and estimated the proportion of foliage remaining below it for all adult individuals of small trees within a 50 x 50 m area, recorded scat numbers, browsing damage to tree seedlings by species and environmental data. The 110-130-cm browse line, and strong relationships between macropod scat numbers and the remaining foliage below the browse line, suggested that Bennetts wallabies (Macropus rufogriseus Shaw) were the main cause of umbrella-shaped trees. The browsers preferred Exocarpos cupressiformis Labill. and Bursaria spinosa Cav. At the other extreme, adult Acacia dealbata Link suffered no browsing damage. All species were browsed as seedlings. Associational resistance occurred in some species and associational susceptibility in others, with the degree of difference in palatability between alternative sources of browse possibly resolving this apparent contradiction. Low browsing pressure is likely to cause woody thickening, an increase in fire hazard and a decrease in biodiversity. Extremely high browsing pressure had no such effects. Animal browsing can transform tree and forest. We found that wallabies and pademelons preferred to eat prickly box and native cherries, and avoided many wattles, but would eat all small trees as seedlings. Their browsing appeared to keep dry forests more open, and less prone to fire damage, than would otherwise have been the case. [ABSTRACT FROM AUTHOR]

A reproducible procedure for induction of somatic embryogenesis (SE) from adult trees of Eucalyptus globulus Labill. and the hybrid E. saligna Smith × E. maidenii F. Muell. has been developed for the first time. Somatic embryos were obtained from both shoot apex and leaf explants of all three genotypes evaluated, although embryogenic frequencies were significantly influenced by the species/genotype, auxin and explant type. Picloram was more efficient for somatic embryo induction than naphthaleneacetic acid (NAA), with the highest frequency of induction being obtained in Murashige and Skoog medium containing 40 μM picloram and 40 mg l-1 gum Arabic, in which 64% of the shoot apex explants and 68.8% of the leaf explants yielded somatic embryos. The embryogenic response of the hybrid was higher than that of the E. globulus, especially when NAA was used. The cultures initiated on picloram-containing medium consisted of nodular embryogenic structures surrounded by a mucilaginous coating layer that emerged from a watery callus developed from the initial explants. Cotyledonary somatic embryos were differentiated after subculture of these nodular embryogenic structures on a medium lacking plant growth regulators. Histological analysis confirmed the bipolar organization of the somatic embryos, with shoot and root meristems and closed procambial tissue that bifurcated into small cotyledons. The root pole was more differentiated than the shoot pole, which appeared to be formed by a few meristematic layers. Maintenance of the embryogenic lines by secondary SE was attained by subculturing individual cotyledonary embryos or small clusters of globular and torpedo embryos on medium with 16.11 μM NAA at 4- to 5-week intervals. Somatic embryos converted into plantlets after being transferred to liquid germination medium although plant regeneration remained poor. [ABSTRACT FROM AUTHOR]

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Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Global climate change is expected to increase the length of drought periods in many tropical regions. Although large amounts of potassium (K) are applied in tropical crops and planted forests, little is known about the interaction between K nutrition and water deficit on the physiological mechanisms governing plant growth. A process-based model (MAESPA) parameterized in a split-plot experiment in Brazil was used to gain insight into the combined effects of K deficiency and water deficit on absorbed radiation (aPAR), gross primary productivity (GPP), and light-use efficiency for carbon assimilation and stem biomass production (LUEC and LUEs) in Eucalyptus grandis plantations. The main-plot factor was the water supply (undisturbed rainfall vs. 37% of throughfall excluded) and the subplot factor was the K supply (with or without 0.45 mol K m−2 K addition). Mean GPP was 28% lower without K addition over the first 3 years after planting whether throughfall was partly excluded or not. K deficiency reduced aPAR by 20% and LUEC by 10% over the whole period of growth. With K addition, throughfall exclusion decreased GPP by 25%, resulting from a 21% decrease in LUEC at the end of the study period. The effect of the combination of K deficiency and water deficit was less severe than the sum of the effects of K deficiency and water deficit individually, leading to a reduction in stem biomass production, gross primary productivity and LUE similar to K deficiency on its own. The modeling approach showed that K nutrition and water deficit influenced absorbed radiation essentially through changes in leaf area index and tree height. The changes in gross primary productivity and light-use efficiency were, however, driven by a more complex set of tree parameters, especially those controlling water uptake by roots and leaf photosynthetic capacities. [ABSTRACT FROM AUTHOR]

Australia houses some unusual biota (insects included), much of which is undescribed. Cystococcus Fuller (Hemiptera : Sternorrhyncha : Coccoidea : Eriococcidae) currently comprises two species, both of which induce galls exclusively on bloodwoods (Myrtaceae: Corymbia Hill & Johnson). These insects display sexual dichronism, whereby females give birth first to sons and then to daughters. Wingless first-instar females cling to their winged adult brothers and are carried out of the maternal gall when the males fly to find mates – a behaviour called intersexual phoresy. Here, we use data from two gene regions, as well as morphology and host-use of the insects, to assess the status of a previously undescribed species. We describe this newly recognised species as Cystococcus campanidorsalis, sp. nov. Semple, Cook & Hodgson, redescribe the two existing species – C. echiniformis Fuller and C. pomiformis (Froggatt), designate a lectotype for C. echiniformis, and provide the first descriptions of adult males, and nymphal males and females for the genus. We have also reinterpreted a key morphological character of the adult females. This paper provides a foundation for further work on the genus, which is widespread across northern Australia and could prove to be useful for studies on biogeography and bloodwood ecosystems. [ABSTRACT FROM AUTHOR]

Land-use change can have significant impacts on soil and aboveground carbon (C) stocks and there is a clear need to identify sustainable land uses which maximize C mitigation potential. Land-use transitions from agricultural to bioenergy crops are increasingly common in Europe with one option being Short Rotation Forestry ( SRF). Research on the impact on C stocks of the establishment of SRF is limited, but given the potential for this bioenergy crop in temperate climates, there is an evident knowledge gap. Here, we examine changes in soil C stock following the establishment of SRF using combined short (30 cm depth) and deep (1 m depth) soil cores at 11 sites representing 29 transitions from agriculture to SRF. We compare the effects of tree species including 9 coniferous, 16 broadleaved and 4 Eucalyptus transitions. SRF aboveground and root biomass were also estimated in 15 of the transitions using tree mensuration data allowing assessments of changes in total ecosystem C stock. Planting coniferous SRF, compared to broadleaved and Eucalyptus SRF, resulted in greater accumulation of litter and overall increased soil C stock relative to agricultural controls. Though broadleaved SRF had no overall effect on soil C stock, it showed the most variable response suggesting species-specific effects and interactions with soil types. While Eucalyptus transitions induced a reduction in soil C stocks, this was not significant unless considered on a soil mass basis. Given the relatively young age and limited number of Eucalyptus plantations, it is not possible to say whether this reduction will persist in older stands. Combining estimates of C stocks from different ecosystem components (e.g., soil, aboveground biomass) reinforced the accumulation of C under coniferous SRF, and indicates generally positive effects of SRF on whole-ecosystem C. These results fill an important knowledge gap and provide data for modelling of future scenarios of LUC. [ABSTRACT FROM AUTHOR]

The aim was to determine the yield of Eucalyptus benthamii and Eucalyptus grandis in the process of the sawing. The methodology involved two diameter classes (20-25 cm and 25.1-30 cm) and two systems sawing (tangential and radial). The yield of sawing was obtained through the relationship between the volume of logs and lumber, being separated into gross yield, no splits, no trimming and liquid. The analysis yield was adopted the Analysis of Variance and Tukey test. The results demonstrated that the system of tangential sawing showed better utilization of raw-material. The treatments consisted of the E. benthamii and tangential system presented the greatest yield reduction due to the removal of parts of the split pieces, while for the loss due to destopo, the percentages found were similar for both species. In the final yield of the process, there was no reduction of yield in lumber with the increase of the diameter of the logs for both species. [ABSTRACT FROM AUTHOR]

Artificial neural networks (ANN) have great potential as an alternative to conventional regression analysis because of its learning capacity of data set information and the generalization of learning to unknown data. So, the aim of this study was to apply RNAs to estimate relative diameter, total and commercial volume, as well as to compare their performance in relation to conventional taper functions. Data from 47 trees of Eucalyptus sp. were used in the training and validation of ANNs and in adjusting Hradetzky and Garay taper functions. The performance of ANNs were similar to the taper functions for diameter estimative, furthermore the estimative of commercial and total volume applying ANNs were more accurate and presented less residues scattering than Garay and Hradetzky function. ANNs were accurate and appropriate for the estimation of volume and relative diameter. [ABSTRACT FROM AUTHOR]

Wood utilization for pulp and paper and biorefinery applications requires some kind of mechanical and/or physical–chemical pretreatment. Among the chemical treatments the alkaline ones are the most used worldwide, although acid and solvent treatments have also being used. This paper deals with eucalypt wood deconstruction with alkaline processes including soda-AQ, soda-AQ-O 2 , soda-O 2 , and kraft. The kraft process is largely used by the pulp industry and is evaluated here only to serve as a reference. The behavior of the four eucalypt clones selected in chapter 2 were investigated when submitted to the aforementioned processes regarding their screened yield, chemical demands and pulp quality at different kappa number levels (15, 35, 50, and 70). The two most promising processes (kraft and soda-AQ) were chosen for producing pulps (kappa 15 and 20) which were studied in depth (content of carbohydrates, uronic acid, hexenuronic acid, polysaccharide molecular weight, residual lignin structure, etc.), as well as their respective black liquors (heating value, solid content, elemental analysis, and lignin structure). The main findings of this work were: (1) the wood of the four different hybrid eucalypt clones behave similarly in the various alkaline deconstruction treatments; (2) the soda-AQ and Kraft were considered the most suitable processes for producing pulp on the basis of yield, chemical demands and pulp fiber integrity; (3) the soda-AQ process can potentially replace the kraft for a high degree of wood delignification (kappa number 15); (4) the alkaline processes using oxygen (soda-AQ-O 2 and soda-O 2 ) are more suitable for wood deconstruction aimed at biofuels; and (5) the soda-AQ process resulted black liquor of more suitable burning characteristics than the kraft. [ABSTRACT FROM AUTHOR]

Do alien invasive species exhibit life history characteristics that are similar to those of native species that have become pests in their continent of origin? We compared eucalypt specialists that have become pests in Australian plantations (natives) to those that have established overseas (aliens) using 13 life history traits and found that although traits that support rapid population build-up were shared, overall, aliens and native colonisers differed significantly. Distance from source (New Zealand vs. other) had no significant effect, but species that established more than 50 years ago exhibited different life history traits from those that established within the last 50 years, possibly because of more effective quarantine. Native and alien eucalypt insect invaders differed predominantly in traits that facilitate long-distance movement (pathway traits), compared to traits that facilitate establishment and spread. Aliens had longer adult flight seasons, were smaller and more closely host-associated (cryptic eggs and larvae), had lower incidence of diapause (i.e. were more seasonally plastic) and more generations per year than natives. Thus, studies of species invasive within their country of origin can shed light on alien invasions. [ABSTRACT FROM AUTHOR]