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Net rhizodeposition corresponds to the portion of living root carbon (C) that remains in the soil after microbial processing and partial decomposition. Although it is assumed that this C input exerts an important role in the formation of soil organic matter (SOM), its contribution to distinct SOM pools is still not fully understood. In this study, we aimed to (i) quantify the retention of net rhizodeposition C in the different SOM fractions and in reactive Al and Fe mineral phases and (ii) investigate how rhizodeposition drives the spatial distribution of microbial communities in the rhizosphere. To track the transfer of net rhizodeposition into the soil, we used artificially labeled eucalypt (Eucalyptus spp.) seedlings under a 13C-CO2 atmosphere (multiple-pulse labeling). Combining physical SOM fractionation and the chemical extraction of aluminum (Al) and iron (Fe) reactive phases, we studied the distribution of net rhizodeposition into different soil fractions. We also assessed the 13C incorporation into microbial phospholipid fatty acids (PLFAs) at different distances from the roots. Our results show that 76 % of the net rhizodeposition 13C was retained within the mineral-associated organic matter (MAOM) fraction. About 28 % of net rhizodeposition 13C within the MAOM fraction was retained within the Al and Fe reactive phases, indicating that this is a sizeable mechanism for the retention of net rhizodeposition in soil. Rhizodeposition increased the abundance of microbial PLFAs exclusively in the soil close to the roots (0–4 mm), with prominent incorporation of net rhizodeposition 13C into fungal biomarkers. Overall, our findings underscore the importance of mineral associations for the retention of net rhizodeposition in the soil. We also highlight the role of fungi in transferring the root-derived C beyond the root vicinity and promoting the formation of occluded SOM.

Wood residues, as well as those from poultry farming, are generally disposed of irregularly, which causes damage to the environment, and thus poses a great challenge in terms of their use, a possible alternative is the manufacture of particleboards. For this, the following mechanical properties of the panels were evaluated: static bending (elasticity – MOE and rupture – MOR), internal bond strength (IB), Janka hardness (DJ), screw withdrawal resistance (SW), thickness swelling (TS), water absorption (WA), moisture, apparent density (DA) and density profile, in addition to morphological characterization by scanning electron microscope image. With the results obtained, it was possible to observe that the amount of residue influenced the density of the panel. The panel compaction ratio showed little variation (1.22–1.32), remaining close to the value considered ideal of 1.33. The percentage of waste added to the panels also influenced the increase in WA and TS, limiting the use of the panels to environments without humidity. The addition of the eggshell in the process negatively affected the mechanical characteristics of formulated particleboards, except for Janka hardness. The application of the resin together with the wood particles and eggshells can improve the mechanical properties. Based on the findings from this study, the medium-density particleboard produced can be used for making furniture and room partitioning without structural character.

IntroductionTranslocation is a valuable and increasingly used strategy for the management of both threatened and overabundant wildlife populations. However, in some instances the translocated animals fail to thrive. Differences in diet between the source and destination areas may contribute to poor translocation outcomes, which could conceivably be exacerbated if the animals’ microbiomes are unsuited to the new diet and cannot adapt.MethodsIn this study we tracked how the faecal microbiome of a specialist Eucalyptus folivore, the koala (Phascolarctos cinereus), changed over the course of a year after translocation. We assessed microbiome composition by 16S rRNA amplicon sequencing of faecal pellets.ResultsWe found no significant overall changes in the faecal microbiomes of koalas post-translocation (n = 17) in terms of microbial richness, diversity or composition when compared to the faecal microbiomes of koalas from an untranslocated control group (n = 12). This was despite the translocated koalas feeding on a greater variety of Eucalyptus species after translocation. Furthermore, while differences between koalas accounted for half of the microbiome variation, estimated diets at the time of sampling only accounted for 5% of the variation in the koala microbiomes between sampling periods. By contrast, we observed that the composition of koala faecal microbiomes at the time of translocation accounted for 37% of between koala variation in post-translocation diet. We also observed that translocated koalas lost body condition during the first month post-translocation and that the composition of the koalas’ initial microbiomes were associated with the magnitude of that change.DiscussionThese findings suggest that the koala gut microbiome was largely unaffected by dietary change and support previous findings suggesting that the koala gut microbiome influences the tree species chosen for feeding. They further indicate that future research is needed to establish whether the koalas’ gut microbiomes are directly influencing their health and condition or whether aspects of the koala gut microbiomes are an indicator of underlying physiological differences or pathologies. Our study provides insights into how animal microbiomes may not always be affected by the extreme upheaval of translocation and highlights that responses may be host species-specific. We also provide recommendations to improve the success of koala translocations in the future.

Abstract Comments are presented on an article published in October 2020 in Ecology and Evolution (“Predictive ability of a process‐based versus a correlative species distribution model”) by Higgins et al. This analyzed natural distributions of Australian eucalypt and acacia species and assessed the adventive range of selected species outside Australia. Unfortunately, inappropriate variables were used with the MaxEnt species distribution model outside Australia, so that large climatically suitable areas in the Northern Hemisphere were not identified. Examples from a previous analysis and from the use of the freely available spatial portal of the Atlas of Living Australia are provided to illustrate how the problem can be overcome. The comparison of methods described in the Higgins et al. paper is worthwhile, and it is hoped that the authors will be able to repeat their analyses using appropriate variables with the correlative model.

Austropuccinia psidii is a biotrophic fungus that causes myrtle rust. First described in Brazil, it has since spread to become a globally important pathogen that infects more than 480 myrtaceous species. One of the most important commercial crops affected by A. psidii is eucalypt, a widely grown forestry tree. The A. psidii–Eucalyptus spp. interaction is poorly understood, but pathogenesis is likely driven by pathogen-secreted effector molecules. Here, we identified and characterized a total of 255 virulence effector candidates using a genome assembly of A. psidii strain MF-1, which was recovered from Eucalyptus grandis in Brazil. We show that the expression of seven effector candidate genes is modulated by cell wax from leaves sourced from resistant and susceptible hosts. Two effector candidates with different subcellular localization predictions, and with specific gene expression profiles, were transiently expressed with GFP-fusions in Nicotiana benthamiana leaves. Interestingly, we observed the accumulation of an effector candidate, Ap28303, which was upregulated under cell wax from rust susceptible E. grandis and described as a peptidase inhibitor I9 domain-containing protein in the nucleus. This was in accordance with in silico analyses. Few studies have characterized nuclear effectors. Our findings open new perspectives on the study of A. psidii–Eucalyptus interactions by providing a potential entry point to understand how the pathogen manipulates its hosts in modulating physiology, structure, or function with effector proteins.

The usage of laccases is a sustainable and environmentally friendly approach to modifying the Kraft lignin structure for use in certain applications. However, the inherent structure of Kraft lignin, as well as that resulting from laccase modification, still presents challenges for fundamental comprehension and successful lignin valorization. In this study, bacterial and fungal laccases were employed to modify eucalypt Kraft lignin. To evaluate the type and range of the chemical and structural changes of laccase-treated lignins, different NMR techniques, including solution 1H and 2D NMR (heteronuclear single quantum correlation (HSQC)), and solid-state 13C NMR, were applied. Size exclusion chromatography and infrared spectroscopy were also used. Interestingly, HSQC analysis showed substantial changes in the oxygenated aliphatic region of lignins, showing an almost complete absence of signals corresponding to side-chains due to laccase depolymerization. Simultaneously, a significant loss of aromatic signals was observed by HSQC and 1H NMR, which was attributed to a deprotonation of the lignin benzenic rings due to polymerization/condensation by laccase reactions. Then, condensed structures, such as α-5′, 5-5′, and 4-O-5′, were detected by HSQC and 13C NMR, supporting the increment in molecular weight, as well as the phenolic content reduction determined in lignins.

Kraft lignin, a side-stream from the pulp and paper industry, can be modified by laccases for the synthesis of high added-value products. This work aims to study different laccase sources, including a bacterial laccase from Streptomyces ipomoeae (SiLA) and a fungal laccase from Myceliophthora thermophila (MtL), for kraft lignin polymerization. To study the influence of some variables in these processes, a central composite design (CCD) with two continuous variables (enzyme concentration and reaction time) and three levels for each variable was used. The prediction of the behavior of the output variables (phenolic content and molecular weight of lignins) were modelled by means of response surface methodology (RSM). Moreover, characterization of lignins was performed by Fourier-transform infrared (FTIR) spectroscopy and different nuclear magnetic resonance (NMR) spectroscopy techniques. In addition, antioxidant activity was also analyzed. Results showed that lignin polymerization (referring to polymerization as lower phenolic content and higher molecular weight) occurred by the action of both laccases. The enzyme concentration was the most influential variable in the lignin polymerization reaction within the range studied for SiLA laccase, while the most influential variable for MtL laccase was the reaction time. FTIR and NMR characterization analysis corroborated lignin polymerization results obtained from the RSM.

Downy mildew (Plasmopara viticola) is the primary disease in viticulture worldwide, and your control requires synthetic fungicides applications to avoid quality and yield loss in the grapevines. However, alternatives to reduce synthetic fungicides are needed to ensure the consumer’s health and the environment. Essential oils (EOs) are amongst the most promising natural plant protection alternatives because of their antifungal properties on several crop diseases. The present study objective was to determine the effect of Eucalyptus staigeriana EO in vitro and in vivo against P. viticola. The EO exhibited the highest activity in vitro, inhibiting 90% of the incidence and severity of disease caused by P. viticola in leaves of grapevines in the greenhouse. In the field (in vivo), treatment with EO could not control the disease; however, treatment with EO in consortium with conventional treatment reduced approximately 50% of the incidence and more than 90% of the severity of downy mildew disease in leaves, decreasing the application of synthetic fungicides by 50%.

Despite the reported allelopathic nature of the Eucalyptus genus, eucalypt leachates have unknown effects on the trophic base of stream green food webs. Eucalypt plantations have increased worldwide, including riparian ecosystems. We aimed to test whether short-term eucalypt leachates might alter water chemistry, periphytic algal biomass and diatoms, and herbivorous invertebrates’ (i.e., scrapers). We studied two oligotrophic and well-preserved headwaters from NW Spain. The experiment followed a before-after control-impact paired (BACIp) design, with weekly sampling before and after eucalypt leaves addition to streams. In the stream with lower discharge, the eucalypt treatments seemed to affect increases in biomass accrual (Chl-a) and diatom assemblages, disfavouring sensitive species (e.g., Eunotia minor and Achnanthidium pyrenaicum). Therefore, the ecological status was reduced from high to good. In the stream with higher discharge, invertebrate assemblages changed with scrapers having their abundances modified in comparison with the control (e.g., Habrophlebia sp. and Elmidae). Results suggest that eucalypt leaves leachates exert toxic effects on periphyton and on diatom and invertebrate assemblages, and this effect might be mediated by discharge. Alterations at the base of stream food webs may compromise their good ecological status. Further studies are necessary to identify whether this toxicity is due to allelopathic processes.

This article presents a method, based on orbital remote sensing, to map the extent of forest plantations in São Paulo State (Southeast Brazil). The proposed method uses the random forest machine learning algorithm available on the Google Earth Engine (GEE) cloud computing platform. We used 30 m annual mosaics derived from Landsat-5 Thematic Mapper (TM) images and from Landsat-8 Operational Land Imager (OLI) images for the 1985 to 1995 and 2013 to 2021 time periods, respectively. These time periods were selected based on the planted areas’ rotation, especially the eucalypt’s short rotation. To classify the forest plantations, green, red, NIR, and MIR spectral bands, NDVI, GNDVI, NDWI, and NBR spectral indices, and vegetation, shade, and soil fractions were used for both sensors. These indices and the fraction images have the advantage of reducing the volume of data to be analyzed and highlighting the forest plantations’ characteristics. In addition, we also generated one mosaic for each fraction image for the TM and OLI datasets by computing the maximum value through the period analyzed, facilitating the classification of areas occupied by forest plantations in the study area. The proposed method allowed us to classify the areas occupied by two forest plantation classes: eucalypt and pine. The results of the proposed method compared with the forest plantation areas extracted from the land use and land cover maps, provided by the MapBiomas product, presented the Kappa values of 0.54 and 0.69 for 1995 and 2020, respectively. In addition, two pilot areas were used to evaluate the classification maps and to monitor the phenological stages of eucalypt and pine plantations, showing the rotation cycle of these plantations. The results are very useful for planning and managing planted forests by commercial companies and can contribute to developing an automatic method to map forest plantations on regional and global scales.

ABSTRACT One of the factors that may affect and limit the production in eucalypt plantations is the attack of defoliating insects. Among those, the brown eucalypt caterpillar, Thyrinteina arnobia (Stoll, 1782) (Lepidoptera: Geometridae), stands out for being the major defoliating pest of Eucalyptus spp. in Brazil. Thus, the present study aimed to investigate the food consumption of T. arnobia, in its native host, guava (Psidium guajava L.), and in the different E. urograndis clones (VE 41, I 144, TP 361 and VCC 865). To assess T. arnobia food consumption, choice and non-choice tests were carried out using the native and the exotic host, alone or in combination. In non-choice tests, it was observed a higher consumption for the VE 41 clone and the native host (guava). The food consumption evaluation in choice tests indicated no food preference of T. arnobia between guava and E. urograndis clones, with the exception for the TP 361 clone, which was significantly less consumed than guava. In choice tests between the different E. urograndis clones, the clone I 144 presented a tendency towards lower food preference, being consumed only after 48 hours. In addition, the leaf consumption was similar between the VE 41, I1 14 e VCC 865 clones. In choice tests using the E. urograndis clones in pairs, the VE 41 clone was more consumed while the I 144 clone was less consumed when compared to the TP 361 clone. The obtained results provide basic information for the indication of eucalypt clones, and the understanding of the interaction and ecological relationships, assisting in the development of Forest Integrated Pest Management (Forest IPM) programs for the control of T. arnobia.

Abstract Cryptococcosis is a fungal infection caused by members of the Cryptococcus gattii and C. neoformans species complexes. The C. gattii species complex has a strong environmental association with eucalypt hollows (particularly Eucalyptus camaldulensis), which may present a source of infection. It remains unclear whether a specific mycobiome is required to support its environmental survival and growth. Conventional detection of environmental Cryptococcus spp. involves culture on differential media, such as Guizotia abyssinica seed agar. Next‐generation sequencing (NGS)‐based culture‐independent identification aids in contextualising these species in the environmental mycobiome. Samples from 23 Australian tree hollows were subjected to both culture‐ and amplicon‐based metagenomic analysis to characterize the mycobiome and assess relationships between Cryptococcus spp. and other fungal taxa. The most abundant genera detected were Coniochaeta, Aspergillus, and Penicillium, all being commonly isolated from decaying wood. There was no correlation between the presence of Cryptococcus spp. in a tree hollow and the presence of any other fungal genus. Some differences in the abundance of numerous taxa were noted in a differential heat tree comparing samples with or without Cryptococcus‐NGS reads. The study expanded the known environmental niche of the C. gattii and C. neoformans species complexes in Australia with detections from a further five tree species. Discrepancies between the detection of Cryptococcus spp. using culture or NGS suggest that neither is superior per se and that, rather, these methodologies are complementary. The inherent biases of amplicon‐based metagenomics require cautious interpretation of data through consideration of its biological relevance.

Abstract Conservation management often uses information on genetic population structure to assess the importance of local provenancing for ecological restoration and reintroduction programs. For species that do not exhibit complete reproductive isolation, the estimation of population genetic parameters may be influenced by the extent of admixture. Therefore, to avoid perverse outcomes for conservation, genetically informed management strategies must determine whether hybridization between species is relevant, and the extent to which observed population genetic patterns are shaped by interspecific versus intraspecific gene flow. We used genotyping by sequencing to identify over 2,400 informative single nucleotide polymorphisms across 18 populations of Eucalyptus regnans F. Muell., a foundation tree species of montane forests in south‐eastern Australia. We used these data to determine the extent of hybridization with another species, Eucalyptus obliqua L'Hér., and investigate how admixture influences genetic diversity parameters, by estimating metrics of genetic diversity and examining population genetic structure in datasets with and without admixed individuals. We found hybrid individuals at all sites and two highly introgressed populations. Hybrid individuals were not distributed evenly across environmental gradients, with logistic regression identifying hybrids as being associated with temperature. Removal of hybrids resulted in increases in genetic differentiation (FST), expected heterozygosity, observed heterozygosity and the inbreeding coefficient, and different patterns of isolation by distance. After removal of hybrids and introgressed populations, mountain ash showed very little population genetic structure, with a small effect of isolation by distance, and very low global FST(0.03). Our study shows that, in plants, decisions around provenancing of individuals for restoration depend on knowledge of whether hybridization is influencing population genetic structure. For species in which most genetic variation is held within populations, there may be little benefit in planning conservation strategies around environmental adaptation of seed sources. The possibility for adaptive introgression may also be relevant when species regularly hybridize.

Abstract The aim of this study was to develop a general applicability equation to represent the hypsometric relationship of Eucalyptus benthamii Maiden et Cambage stands in Irani, Santa Catarina. The data came from a continuous forest inventory, with a simple random sampling design and the Bitterlich method. The functions to represent the hypsometric relationship were adjusted with their parameters linear function of stands variables, based on the Gauss-Newton algorithm. The models were evaluated according to the criteria of adjustment and precision, accuracy and validation. In general, the Harrison model, adjusted with the coefficient “c” linear function of age, dominant diameter and basal area, presented the best statistical performance to represent the hypsometric relationship of Eucalyptus benthamii.

ABSTRACT Eucalyptus cloeziana is one of the highest-density wood species offering significant added value, frequently used in the construction and furniture industries. Despite its suitability, it may be overlooked on account of its propagation difficulties due either to its low rooting cutting capacity or to its seeds having a low germination rate perhaps attributable to the high proportion of indistinguishable impurities within the seed lots. This study aimed to develop an efficient technique for Eucalyptus cloeziana seed processing to increase the physical purity and, consequently, the physiological quality of the seed lot. Three seed lots, separated by size in sieves with 1.18, 1.00, and 0.84 mm square openings, were used. X-ray analyses were carried out, the number of normal seedlings and germination rate identified and the percentage and speed of seedling emergence under greenhouse conditions ascertained. The greenhouse evaluation showed that the seed retained in the 1.18 mm sieve presented viability and vigor twice that of the control. Therefore, the processing technique by size classification is efficient in terms of improving the physical and physiological performance of Eucalyptus cloeziana seed lots.

Forest Red Gum eucalypt provides a versatile wood and is converted into different purposes. However, such wood is somewhat limited in structural ends, which highlights the need to exploit this gap through diffusion of mechanical properties of such timber. Obtained results should assist engineers and architects in decision-making for its best building application. This paper studied two physical and fourteen mechanical properties evaluation of Eucalyptus tereticornis at two different moisture contents, following the prescriptions of Brazilian (ABNT NBR 7190: 1997) and North American (ASTM D-143-14: 2014) standard documents. Thus, 1091 repeats were carried out for all properties. By a moisture reduction from 30% to 12%, the bulk density and eleven strength properties statistically showed changes such as modulus of rupture (static bending, parallel and perpendicular compressions), modulus of elasticity (perpendicular compression and static bending), shear stress, tangential cleavage, and parallel and perpendicular hardnesses. Then, the Eucalyptus tereticornis timber could be better usable if is further applied for structural construction uses.

Forest Red Gum eucalypt provides a versatile wood and is converted into different purposes. However, such wood is somewhat limited in structural ends, which highlights the need to exploit this gap through diffusion of mechanical properties of such timber. Obtained results should assist engineers and architects in decision-making for its best building application. This paper studied two physical and fourteen mechanical properties evaluation of Eucalyptus tereticornis at two different moisture contents, following the prescriptions of Brazilian (ABNT NBR 7190: 1997) and North American (ASTM D-143-14: 2014) standard documents. Thus, 1091 repeats were carried out for all properties. By a moisture reduction from 30% to 12%, the bulk density and eleven strength properties statistically showed changes such as modulus of rupture (static bending, parallel and perpendicular compressions), modulus of elasticity (perpendicular compression and static bending), shear stress, tangential cleavage, and parallel and perpendicular hardnesses. Then, the Eucalyptus tereticornis timber could be better usable if is further applied for structural construction uses.

Leaf biochemical traits indicating early symptoms of plant stress can be assessed using imaging spectroscopy combined with radiative transfer modelling (RTM). In this study, we assessed the potential applicability of the leaf radiative transfer model Fluspect-Cx to simulate optical properties and estimate leaf biochemical traits through inversion of two native Australian eucalypt species: Eucalyptus dalrympleana and E. delegetensis. The comparison of measured and simulated optical properties revealed the necessity to recalibrate the refractive index and specific absorption coefficients of the eucalypt leaves’ biochemical constituents. Subsequent validation of the modified Fluspect-Cx showed a closer agreement with the spectral measurements. The average root mean square error (RMSE) of reflectance, transmittance and absorptance values within the wavelength interval of 450–1600 nm was smaller than 1%. We compared the performance of both the original and recalibrated Fluspect-Cx versions through inversions aiming to simultaneously retrieve all model inputs from leaf optical properties with and without prior information. The inversion of recalibrated Fluspect-Cx constrained by laboratory-based measurements produced a superior accuracy in estimations of leaf water content (RMSE = 0.0013 cm, NRMSE = 6.55%) and dry matter content (RMSE = 0.0036 g·cm−2, NRMSE = 21.28%). The estimation accuracies of chlorophyll content (RMSE = 8.46 µg·cm−2, NRMSE = 24.73%), carotenoid content (RMSE = 3.83 µg·cm−2, NRMSE = 30.82%) and anthocyanin content (RMSE = 1.69 µg·cm−2, NRMSE = 37.12%) were only marginally better than for the inversion without any constraints. Additionally, we investigated the possibility to substitute the prior information derived in the laboratory by non-destructive reflectance-based spectral indices sensitive to the retrieved biochemical traits, resulting in the most accurate estimation of carotenoid content (RMSE = 3.65 µg·cm−2, NRMSE = 29%). Future coupling of the recalibrated Fluspect with a forest canopy RTM is expected to facilitate retrieval of biophysical traits from spectral air/space-borne image data, allowing for assessing the actual physiological status and health of eucalypt forest canopies.

ABSTRACT Over the years, the species of eucalyptus has become a multipurpose raw material. In addition, the most relevant aspect of the use for various purposes is related to the production of a high quality wood, coming from short duration plantations, which is fundamental to the current demand of the industries. However, its use in civil construction has not yet reached a level of importance, due to the low knowledge of many of its resistance properties and the consequent popular fear in the use of reforestation woods, in particular the Eucalyptus grandis. This research investigated its main mechanical properties, aiming to reinforce its constructive applications in wood structures. For this, two physical properties and fourteen mechanical properties, in two different moisture conditions of the samples were evaluated, according to the norm NBR 7190 (1997). In the first moisture content, the samples were stabilized at 30%, while the second level considered the content of 12%. It was obtained 3580 determinations for the sixteen properties. From the 14 mechanical properties, only 7 had significant increases with the moisture reduction (30% to 12%), consisting of the rupture modulus in the parallel and normal compressions, normal traction and static bending; modulus of elasticity in normal compression and static bending and in shear strength.

Abstract Woody debris plays an important role in many ecosystem functions, including nutrient and carbon cycling, providing substrates for plant recruitment and habitat for fauna. Fires can affect woody debris stocks, through generating new pieces by killing or severing plant parts and consuming pre‐existing woody debris. We develop a model of woody debris dynamics with variation in time since fire and prior fire interval applicable to obligate‐seeder forests and woodlands, considering down woody debris and standing dead trees as discrete components. We then test predictions of change in woody debris derived from this model in Eucalyptus salubris woodlands in South‐Western Australia, using a multi‐century chronosequence with recent fires varying between having short (50 yr, but often much longer) prior intervals. As per our woody debris dynamics model, most attributes measured were affected by time since fire, prior fire interval, or their interaction. Woody debris biomass was greatest shortly after fire, reflecting high quantities of standing dead trees resulting from stand‐replacement disturbance. Standing dead tree density and biomass then declined with increasing time since fire, but individual dead tree size was high beyond 200 yr since fire. Down woody debris biomass remained relatively stable with time since fire, but piece size increased. Dimensions of woody debris were strongly influenced by prior fire interval, with long prior intervals resulting in pieces at least twice the size than those occurring after short prior intervals. Fire management to maximize the availability of large woody debris pieces for fauna should aim to minimize short fire intervals, while from a carbon management perspective, all fires in obligate‐seeder forests and woodlands set in train large and prolonged emissions of carbon.

O presente trabalho teve como objetivo analisar o crescimento e taxa de sobrevivência de um plantio florestal experimental com quatro espécies do gênero Eucalyptus, E. dunnii, E. benthamii, E. cloesiana e E. saligna, na cidade de Canoinhas – SC. O talhão florestal contém 10 linhas com 25 árvores cada, a um espaçamento 3 m x 3 m em área de 2.250 m2 com idade de 5 anos. O censo florestal foi realizado com trena e fita métrica para a medição do diâmetro e hipsômetro para a medição em altura. As medições foram realizadas nos anos de 2012, 2013, 2014, 2015 e 2016. Foram calculados a taxa de sobrevivência, o Incremento Médio Anual – IMA e o Incremento Corrente Anual – ICA ao longo dos anos. Também foram avaliadas a distribuição diamétrica e a altura média para cada espécie. Os melhores IMAs foram de E. benthamii, E. dunnii e E. saligna, respectivamente 46,21, 42,87 e 40,77 m3 .ha-1.ano-1. A espécie com o pior desempenho foi E. cloesiana com 12,24 m3 .ha-1.ano-1. As espécies E. benthamii, E. dunnii e E. saligna atingiram a idade técnica de corte. As taxas de sobrevivência foram de 96% para E. dunniii, 94% para E. saligna, 82% para E. benthamii e 80% para E. cloesiana. Os resultados permitem dizer que a espécie E. cloesiana é a menos adaptada para o clima do local de estudo, com baixa taxa de sobrevivência e menor crescimento. The present work aimed to analize the growth and survival rate of an experimental forest plantation with four species of the genera Eucalyptus, E. dunnii, E. benthamii, E. cloesiana and E. saligna, in the city of Canoinhas – SC. The forest area contains 10 lines with 25 trees each, at a spacing of 3 m x 3 m with an area of 2,250 m2 and five years old. The forest census was carried out with measuring tape for diameter measurement and hypsometer for height measurement. Measurements were made in 2012, 2013, 2014, 2015 and 2016. The survival rate, the Mean Annual Increment – MAI and the Periodic Annual Increment – PAI over the years were calculated. The diameter distribution and mean height for each species were also evaluated. The best MAIs were E. benthamii, E. dunnii and E. saligna, respectively 46.21, 42.87 and 40.77 m3 .ha-1.year-1. The species with the worst performance was E. cloesiana with 12.24 m3 .ha-1.year-1. The species E. benthamii, E. dunnii and E. saligna reached the technical cutting age. The survival rates were 96% for E. dunniii, 94% for E. saligna, 82% for E. benthamii and 80% for E. cloesiana. The results suggest that the E. cloesiana species is less adapted to the climate of the study site, with a lower survival rate and lower growth.

One-year seedlings of five species of eucalypt: E. camaldulensis, E. microtheca, E. viminalis, E. globulus and E. gunnii were treated for 14 weeks in growth season, tilting a branch to c. 60° in every successful ones. We investigated the anatomical features of stems wood after 15 days and every 2 weeks according to IAWA list of features afterwards.The results showed that tilted stems formed more tension wood in the form of gelatinous fibers than straight (untreated) ones. The formation of gelatinous fibers was considered to be closely related to tension wood formation. The formation of gelatinous fibers was considered to be closely related to tension wood formation. Excluding E. globulus, all the other species formed growth eccentricity and tension wood. Although the significant differences between the species and between different locations in the branches, there were no significant differences between the percent of tension wood among the species studied.

The objective of this work was to evaluate the initial growth and the physiological characteristics of eucalypt submitted to different managements of signalgrass. The experiment was conducted in a protected environment, using a randomized blocks design with five repetitions. The treatments were arranged in a (5 x 2) + 1 factorial design, and the first factor corresponded to the types of weed management (no control; chemical control keeping the signalgrass shoot on the soil; chemical control with removal of the signalgrass shoot; mechanical control keeping the signalgrass shoot on the soil, and mechanical control with removal of the signalgrass shoot); the second factor corresponded to the two weeds species (U. brizantha and U. decumbens) and a control relative to the eucalypt in monoculture. The eucalypt growth was not affected by the presence of the Urochloa species until 50 days after treatments (DAT). However, the coexistence of these species with eucalypt for 107 DAT reduced the collar diameter, total dry matter, and the leaf area, but did not alter the characteristics related to photosynthesis and transpiration. The control method adopted, with removal or maintenance of the signalgrass shoot, regardless of species, did not change the initial eucalypt growth. It can be concluded that the coexistence of eucalypt with Urochloa decumbens or Urochloa brizantha for 105 days reduces the eucalypt growth. However, the use of chemical or mechanical control, with or without removal of signalgrass residue, were effective methods to prevent interference of these weeds.

Aim of the study was to estimate the influence of the fiber length and basic density on microfibril angle of Eucalyptus microcorys wood. The study area was in an experimental planting at the Universidade Federal de Lavras, Minas Gerais State, Brazil. Three 37 year-old Eucalyptus microcorys trees were used, from whose stems six centimeter-thick discs were removed, cut at a high of three meters. The disks were sanded and planed to highlight the growth rings. Specimens were taken every 1.5 cm across the radius from pith to bark for determining microfibril angle, fiber length and wood basic density. The microfibril angles were determined by use of polarized light microscopy, while the fiber morphology and basic density were determined by usual methods. The averages found for microfibril angle (12.6°), fiber length (968 µm) and basic density (480 kg.m-3) are, in general, within the range of values reported for these characteristics of wood. The microfibril angle showed accentuated reduction of the average values in the pith-bark direction. The fiber length and basic density showed the opposite behavior. We observed that the density and fiber length may be used as an microfibril angle predictor, accounting for 96% and 79% of its variation, respectively.

In the Baixo Vouga region of north-central Portugal, forests occupy half of the territory, of which two thirds are Eucalypts plantations. The hydrological implications of this large-scale introduction of eucalypt are unknown and the aim of this exploratory study, realized in the Caramulo Mountains, was to describe overland flow (OLF), subsurface flow (SSF) and stream flow (Q) in a catchment dominated by Eucalyptus plantations. The main conclusions are that annual OLF rate is low, spatially heterogeneous between 0.1% and 6% and concentrated during the wet season as saturation excess, particularly as return flow. Infiltration-excess OLF due to the strong soil water repellence (SWR) is dominant during dry season, but produces residual runoff amount. SSF is the principal mechanism of runoff formation. It originates from matrix flow and pipe flow at the soil-bedrock interface, principally during the wet season. Matrix flow is correlated with soil moisture (SM) content, with a threshold of 25 %. Pipe flow starts with saturation of soil bottom but without saturation of the entire soil profile, due to a large network of macropores. Stream flow response is highly correlated with matrix flow behaviour in timing and intensity. SWR induces a very patchy moistening of the soil, concentrates the fluxes and accelerates them almost 100 times greater than normal percolation of the water in the matrix.

As diversas formas de se amostrar a madeira para o estudo de suas propriedades levam em consideração a acurácia, o tempo e o custo de processamento e coleta do material. No entanto, a forma e intensidade da amostragem considerada pode não captar corretamente a variabilidade dessas propriedades ou até mesmo negligenciá-la. O objetivo deste trabalho foi estimar o número de árvores necessárias para a estimativa da densidade básica média da árvore em um clone de híbrido de Eucalyptus urophylla x Eucalyptus grandis considerando diferentes formas de amostragem e classes de diâmetro. Foram utilizadas 50 árvores de um clone do hibrido, aos 5,6 anos. As árvores foram distribuídas em três classes de diâmetro e amostradas na forma de discos, a partir de três propostas: tradicional (0%, 25%, 50%,75% e 100% da altura comercial Hc); alternativa (2%, 10%, 30% e 70% Hc) e de metro em metro a partir do DAP. Não houve diferença entre o número de árvores requeridas para a estimativa da densidade do clone por forma de amostragem, admitindo-se um erro de 5% e intervalo de confiança de 95%. A amostragem alternativa foi a mais eficiente considerando a intensidade da amostragem no tronco e o coeficiente de variação. A classificação diamétrica resultou em um número maior de árvores para estimar a densidade média, em função da maior variação da propriedade dentro de classes do que dentro do método de amostragem. There are several methods of collecting wood samples for the study of their properties, which consider the accuracy, time and cost of collecting and processing the material. However, often the variation pattern of ownership in the tree is neglected. Depending on the shape and size of the sample in the study the variability of the properties of the wood cannot be properly captured. The aim of this study was to estimate the number of trees needed to estimate the average basic density of the tree in a Eucalyptus urophylla x Eucalyptus grandis hybrid clone, considering different longitudinal sampling and diameter classes. For this, 50 trees were used to hybrid from clone with 5.6 years. The trees were divided into three diameter classes and sampled in the form of discs, three ways: traditional (0%, 25%, 50%, 75% and 100% of the commercial height Hc); alternative (2%, 10%, 30% and 70% Hc) and every meter from DAP. There was no difference between the number of trees required to estimate the density of the clone regardless sampling form, assuming an error of 5% and a confidence interval of 95%. Alternative sampling was considered most effective, considering the sample size along the stem and the coefficient of variation. Classification by diameter resulted in a greater number of trees to estimate the average density due to greater property variation within diameter classes than within the sampling method

A knot is a natural defect that degrades the quality of softwood and hardwood veneer. To improve efficiency, the plywood industry needs a rapid, inexpensive method of knot identification that is easy to operate and industrialize. Although a non-contact knot-detection technology based on NIR spectroscopy and soft independent modeling of class analogy (SIMCA) has been successful in detecting softwood knots, it has not yet been explored in eucalypt (hardwood) veneer. This study investigated the interaction between knot size, spectral pretreatment methods, and wavelength range selections on this model’s classification accuracy of knots and normal eucalypt wood. The study found that classification results were accurate up to 94.4% for large knot samples (10 to 15 mm in diameter) and up to 100% for knot-free samples. Spectral data for small knots (< 5 mm in diameter) impeded the model’s classification accuracy because of confusion between small knots and both large knots and normal wood. Calibration models developed with second-derivative spectra exhibited the highest accuracy, followed by models built with first-derivative spectra, models based on spectra transformed by vector normalization, and the model based on the raw spectroscopy. Wavelength ranges of 1100 to 2500 nm enabled greater classification accuracy than wavelength ranges of 780 to 1100 nm or 780 to 2500 nm.

Low temperature is the main limiting factor for cultivation expansion, fast growth, and high yield of Eucalyptus species. To investigate the mechanism of their cold tolerance, a cDNA subtraction library representing the cold-induced genes of Eucalyptus dunnii was constructed using suppression subtractive hybridization (SSH) technique. A gene encoding a calmodulin-binding protein (CaMBP) was identified from the SSH library, and the expression pattern of CaMBP under cold stress was further evaluated through reverse transcription - quantitative polymerase chain reaction (RT-qPCR). The expressions of EguCBF1a and EdCaMBP increased already after 4 h of the cold stress, supporting the idea that the CaMBP gene may have a function in the survival of Eucalyptus during winter. A full-length mRNA sequence of 1 808 bp was obtained via a rapid amplification of cDNA ends method, and the sequence was subsequently deposited to GenBank (accession No. JX401571). The CaMBP cDNA of E. dunnii contained a single open reading frame of 1 362 bp, a 5t' untranslated region of 175 bp, and a 3t' untranslated region of 268 bp. Multiple sequence alignment and phylogenetic analysis indicated that CaMBP of E. dunnii shared 56 to 84 % identities with the CaMBPs of other plants and was similar to that of Ricinus communis, Medicago truncatula, and Gossypium hirsutum.

RESUMO O objetivo deste trabalho foi avaliar os estoques de biomassa, carbono e nitrogênio da serapilheira acumulada em um fragmento de Floresta Estacional Semidecidual Montana e dois plantios florestais puros (um de Pterogyne nitens e outro de Eucalyptus urophylla), no sudoeste da Bahia. As amostragens da serapilheira foram realizadas nos períodos chuvoso e seco. A biomassa da serapilheira acumulada foi superior no povoamento de eucalipto (13,1 Mg.ha–1) e inferior no povoamento de P. nitens (1,5 Mg.ha–1), atingindo valores intermediários na floresta nativa (6,3 Mg.ha–1). Essa mesma sequência foi verificada para os estoques de carbono: 5,6 Mg.ha–1 (eucalipto), 2,7 Mg.ha–1 (floresta nativa) e 0,6 Mg.ha–1 (P. nitens). O povoamento P. nitens apresentou teores de N da serapilheira foliar compatíveis aos da floresta nativa. As maiores diferenças de biomassa, carbono e nitrogênio da serapilheira acumulada entre as estações chuvosa e seca foram verificadas nos povoamentos puros.

Compared with purpose-built units, excavator-based harvesters offer many advantages, but they also face one main limitation: a much higher fuel consumption, which also results in higher CO2 emission levels. The fuel efficiency of excavator-based harvesters can be increased by a better interface between the excavator and the harvester head. This study aimed to determine the performance of a new adaptation kit, specifically designed to improve the communication between these two components. The new kit offers real-time adjustment between the power demand of the harvester head and the power output of the excavator, which should help reducing fuel consumption while stabilizing hydraulic fluid temperature. The test was conducted on 53 excavator-based harvesters purchased and managed by a large Brazilian company. Time use, fuel consumption and production were monitored continuously for one full month, before and after installation of the kit. Overall, the study covered 40,000 h of work, during which the harvesters cut, processed, and debarked 4.5 million trees, or 650,000 m3 of wood, under bark. Fuel consumption amounted to 900,000 liters. After installing the adaptation kit, productivity increased 6%, while fuel consumption per hour decreased 3.5%. Fuel consumption and CO2 emissions per product unit decreased 10%, as an average. The effect of random variability typical of an observational study prevented formulating an accurate figure for the amount of fuel that can be saved by installing the adaptation kit. Yet, one may confidently state that, in most cases, installing the kit results in a reduction of fuel use, and that such reduction is most often in the range from −10 to −20% on a per m3 basis.

O preparo de solo é uma das práticas mais antigas no cultivo de plantas. Atualmente, a subsolagem é o método mais difundido e utilizado em povoamentos florestais. Apesar disso, poucos estudos apresentam a produtividade madeireira ao final do ciclo em Eucalyptus cultivados através da subsolagem comparando-a a métodos de intensidades distintas, como o coveamento e a gradagem pesada. Assim, o objetivo do trabalho foi avaliar a produtividade Eucalyptus grandis x Eucalyptus urophylla clonal ao final do ciclo sob diferentes métodos de preparo de solo. Avaliou-se o Incremento Médio Anual, aos 72 meses, em dois tipos de solo representativos de plantios florestais: Neossolo Quartzarênico com 3% de argila e Latossolo Vermelho com 45% de argila. Comparou-se a subsolagem na profundidade de 60 centímetros com o coveamento manual e com a gradagem pesada, que correspondem a preparos menos e mais intensivos, respectivamente. A produtividade madeireira do coveamento aos 72 meses foi 16 e 17% inferior àquela obtida com a subsolagem para o Neossolo Quartzarênico e para o Latossolo Vermelho, respectivamente. Já a gradagem pesada não apresentou diferença de produtividade em relação à subsolagem. Os resultados evidenciam que mesmo em solos arenosos, que possuem baixa susceptibilidade à compactação, a subsolagem deve ser realizada a depender da intensidade de tráfego de máquinas em rotações anteriores. Além disso, com os resultados obtidos se valida a subsolagem como um método adequado de preparo para solos argilosos, não necessitando um método mais intensivo, que proporciona maior risco à erosão e custos mais elevados quando comparado à subsolagem. Soil preparation is one of the oldest practices in the cultivation of plants. Currently, subsoiling is the most widespread and used practice in forest stands in Brazil. Nevertheless, few studies have measured timber productivity at the end of rotation in Eucalyptus under soil subsoiling comparing with different methods, such as pitting and disk harrowing. So, the objective of the study was to evaluate the productivity of Eucalyptus grandis x Eucalyptus urophylla at the end of rotation under different methods of soil preparation. We evaluated the Mean Annual Increment of an Eucalyptus plantation 72 months-old in two soil types representative of forest plantations: a Quartzarenic Neosol with 3% clay content and a Red Oxisol with 45% of clay content. Subsoiling with 60 centimeters depth was compared with manual pitting and disc harrowing corresponding to more and less intensity preparation, respectively, the most widely used method to establish Eucalyptus. The wood productivity with pitting at 72 months was 16 and 17% lower than that obtained with subsoiling to Neosol and Oxisol, respectively. Disc harrowing showed the same productivity in relation to subsoiling. The results show that even in sandy soils, which have low susceptibility to soil compaction, subsoiling should be performed depending on the traffic intensity of machines in previous rotations. Furthermore, the results obtained consider subsoiling a method of soil preparation enough for the two soil types and does not require a more intensive soil preparation, which provides greater erosion risk and a higher cost when compared to subsoiling.

O avanço das pragas exóticas do gênero Eucalyptus, no Brasil, está cada vez maior. A vespa-da-galha Leptocybe invasa Fisher & La Salle (Hymenoptera: Eulophidae) já é encontrada em nove estados brasileiros. O objetivo do trabalho foi avaliar a eficiência de inseticidas sistêmicos aplicados no viveiro de mudas, via rega, para controle de L. invasa. O experimento foi conduzido no viveiro da ESALQ/USP, em Piracicaba–SP, com mudas de Eucalyptus camaldulensis. O teste utilizou os inseticidas Imidacloprid e Tiametoxam nas dosagens 4,1, 8,3 e 12,5 g.m-2 e 37,5, 75 e 112,5 g.m-2, respectivamente. A eficiência foi determinada pelo total de galhas encontradas nas mudas. A eficicácia foi de 84,41% e 61,03%, nas doses de 12,5 g.m-2 e 112,5 g.m-2, respectivamente. O efeito residual dos inseticidas variou de quatro a oito semanas, sem manifestação de fitotoxidade. Os melhores resultados foram obtidos com o Imidacloprid, quando comparado com o Tiametoxam, tanto em eficiência quanto no efeito residual.The advancement of exotic pests of Eucalyptus in Brazil is increasing. The blue gum chalcid wasp (Leptocybe invasa Fisher & La Salle) is already found in nine Brazilian states and there is still no effective control method. The purpose of this study was to determine the efficiency of systemic insecticides to control Leptocybe invasa in nursery seedlings. The experiment was conducted in the nursery of ESALQ/USP, in Piracicaba–SP, with seedlings of Eucalyptus camaldulensis. The test used the insecticides Imidacloprid and Thiamethoxam at doses 4.1, 8.3 and 12.5 g.m-2 and 37.5, 75 and 112.5 g.m-2. Efficiency was determined by the total galls found in seedlings. The insecticides showed efficiency of 84.41% and 61.03% at doses of 12.5 g.m-2 and 112.5 g.m-2. The residual period of insecticides ranged from four to eight weeks with no manifestation of phytotoxicity. The Imidacloprid obtained better results than Thiamethoxam, both in efficiency and in the residual effect.

The purpose of this study was to assess how terracing affected overland flow and associated sediment losses, at the micro-plot scale (0.25 m2), in recently burnt stands of the two principal forest types in north-central Portugal, i.e. mono-specific stands of Maritime Pine and Eucalypt. Terracing is an increasingly common practice of slope engineering in the study region but its impacts on runoff and erosion are poorly studied. Non-terraced plots at the Eucalypt and the Pine site revealed similar median runoff coefficients (rc: 20-30%) as well as comparable median sediment losses (15-25 g m-2) during the first seven months following wildfire. During the ensuing, slightly wetter 18-month period, however, non-terraced plots at the Pine site lost noticeably more sediments (in median, 90 vs. 18 g m-2), in spite the runoff response had remained basically the same (median rc: 33 vs. 28%). By contrast, terraced plots at the same Pine site lost hugely more sediments (in median, 1,200 g m-2) during this 18-month period. Terraced plots at the Eucalypt site even lost three times more sediments (in median, 3,600 g m-2). Ground cover and resistance to shear stress seemed to be key factors in the observed/inferred impacts of terracing.

Salinity effects on plant can often be related to mineral ion content alteration, including phosphate. Under saline conditions, phosphate levels were reported to decrease in plants. Such effects could indirectly affect intracellular phosphate levels, leading to phosphate deficiency, which in turn leads to increased activities of phosphate uptake mechanisms. This research was aimed to investigate the effects of salinity on the expression changes of phosphate transporter genes isolated from E. camaldulensis x E. globulus hybrid clones subjected to salt concentrations of 0 (control), 50, 100, and 150 mMNaCl. Fragments of genes (1164bp long and encodes 304 amino acid polypeptides) known to be involved in phosphate uptake were identified and isolated by RACE from these hybrids, encoding a Phosphate Transporter (Ecg PT). Expression studies using Northern-Blot analysis revealed that the expression of EcgPT was found to be affected by salt, suggesting a direct effect of salinity on phosphate uptake. EcgPT was expressed differently in different clones, indicating different degrees of phosphate transporter activation in order to tolerate salt stress. Molecular data are discussed in relation to measurements of ion levels in different organs of different clones and under various salt regimes during the course of the hydroponic experiment.

Pruning of live branches is a management option to enhance wood quality in plantation trees. It may also alter whole-tree water use, but little is known about the extent and duration of changes in transpiration. In this study, sap flow sensors were used to measure transpiration for 14 days prior to, and 75 days following the removal, through pruning, of the lower 50% of the live-crown length of 10–11 m tall four-year old Eucalyptus pilularis Sm. and E. cloeziana F. Muell. trees. Pruning had no effect on stem growth, sapwood water content or radial pattern of sap velocity in either species. Pruning reduced mean daily water use by 39% in E. pilularis and 59% in E. cloeziana during the first eight days after pruning. Thirty six days after pruning there were no longer any significant differences in transpiration rates between pruned and unpruned trees in either species. Our results show that pruning of live branches had only a short-term effect on whole-tree transpiration in these sub-tropical eucalypt species.

In order for a lignocellulosic bioenergy feedstock to be considered sustainable, it must possess a high rate of growth to supply biomass for conversion. Despite the desirability of a fast growth rate for industrial application, it is unclear what effect growth rate has on biomass composition or saccharification. We characterized Klason lignin, glucan, and xylan content with response to growth in Corymbia interspecific F1 hybrid families (HF) and parental species C. torelliana (CT) and C. citriodora subspecies variegata (CCV) and measured the effects on enzymatic hydrolysis from hydrothermally pretreated biomass. Analysis of biomass composition within Corymbia populations found similar amounts of Klason lignin content (19.7-21.3%) among parental and hybrid populations, whereas glucan content was clearly distinguished within CCV (52%) and HF148 (60%) as compared to other populations (28-38%). Multiple linear regression indicates that biomass composition is significantly impacted by tree size measured at the same age, with Klason lignin content increasing with diameter breast height (DBH) (+0.12% per cm DBH increase), and glucan and xylan typically decreasing per DBH cm increase (-0.7% and -0.3%, respectively). Polysaccharide content within CCV and HF-148 were not significantly affected by tree size. High-throughput enzymatic saccharification of hydrothermally pretreated biomass found significant differences among Corymbia populations for total glucose production from biomass, with parental CT and hybrids HF-148 and HF-51 generating the highest amounts of glucose (~180 mg/g biomass, respectively), with HF-51 undergoing the most efficient glucan-to-glucose conversion (74%). Based on growth rate, biomass composition, and further optimization of enzymatic saccharification yield, high production Corymbia hybrid trees are potentially suitable for fast-rotation bioenergy or biomaterial production.

The leaf area index (LAI) is a key characteristic of forest ecosystems. Estimations of LAI from satellite images generally rely on spectral vegetation indices (SVIs) or radiative transfer model (RTM) inversions. We have developed a new and precise method suitable for practical application, consisting of building a species-specific SVI that is best-suited to both sensor and vegetation characteristics. Such an SVI requires calibration on a large number of representative vegetation conditions. We developed a two-step approach: (1) estimation of LAI on a subset of satellite data through RTM inversion; and (2) the calibration of a vegetation index on these estimated LAI. We applied this methodology to Eucalyptus plantations which have highly variable LAI in time and space. Previous results showed that an RTM inversion of Moderate Resolution Imaging Spectroradiometer (MODIS) near-infrared and red reflectance allowed good retrieval performance (R2 = 0.80, RMSE = 0.41), but was computationally difficult. Here, the RTM results were used to calibrate a dedicated vegetation index (called “EucVI”) which gave similar LAI retrieval results but in a simpler way. The R2 of the regression between measured and EucVI-simulated LAI values on a validation dataset was 0.68, and the RMSE was 0.49. The additional use of stand age and day of year in the SVI equation slightly increased the performance of the index (R2 = 0.77 and RMSE = 0.41). This simple index opens the way to an easily applicable retrieval of Eucalyptus LAI from MODIS data, which could be used in an operational way.

The objective of this study was to evaluate the efficiency of use of the Frechet function for modeling the diameter structure of eucalypt. We used data from permanent plot inventory, measured at ages 28, 40, 52, 64, 76 and 84 months. Set for every occasion and share with the function Frechet 3 and 2 parameters and using the location parameter of the stand as the minimum diameter (γ = dapmin). The function was fitted by maximum likelihood method. The adhesion function to the data was verified by applying the Kolmogorov-Smirnov (K-S. The construction of the diametric distribution model based on the correlation of the pdf parameters stand characteristics. All adjustments to the data presented adherence by K-S test.The equations that comprise the model of the diameter distribution of 2P and γ = dapmin showed no bias in their estimates, and may be used to describe the diameter distribution of even-aged stands.

Native or exotic woody plants can proliferate in dry and moist eucalypt ecosystems shading out many other native species, contributing to chronic decline of eucalypts and reinforcing unnatural fire regimes and nutrient cycling processes. Whether native or exotic, they proliferate as a consequence of disturbances which impact directly on these ecosystems. The most extensive ongoing disturbance since European occupation of Australia has been the disruption of frequent mild burning by humans. This burning maintained dynamically stable nutrient cycling processes and a competitive balance in dry and moist eucalypt systems and prevented plant “invasions”.

The knowledge of breeding impacts on the genetic diversity of hybrids of Eucalyptus is crucial to the exploration of genetic resources. We estimated genetic polymorphic parameters of 112 hybrids of Eucalyptus spp. using 10 genomic simple sequence repeats (SSR) markers and 10 expressed sequence tags (EST) microsatellite markers. According to Student's t-test, there were no significant differences between genomic SSR and EST-SSR markers. Our results also revealed high polymorphism in the hybrids analyzed, indicating that both markers are appropriate for use in genetic breeding programs.

The objective of this work was to evaluate some wood properties of a clone of Eucalyptus urophylla in the radial direction and in two positions along the trunk. The studied material came from Votorantim Metais Zinco S.A., and the plantations, located in Vazante, State of Minas Gerais, Brazil, were six years old. Six trees were harvested from which were cut two logs with three meter long each. Those logs were sawed into thick diametral slabs. A one-meter sample was obtained from these planks in the radial direction. Following this,samples were taken for the evaluation of specific gravity and apparent density, shrinkage from green or from 12% moisture, fiber and vessel sizes and static bending properties. It was foundthat basic and apparent specific gravities, total longitudinal shrinkage, fiber length, vessel diameter and moduli of rupture and elasticity tended to increase in the bark-to-pith direction,while partial longitudinal shrinkage, the tangential/radial ratios and the vessel frequency were reduced. Radial and tangential shrinkages, width, lumen diameter and fiber wall thickness showed different patterns of variation. Only partial volumetric, radial shrinkages and vessel frequency showed different values between the two logs taken from the same tree. The main correlations observed were between modulus of elasticity and of rupture with either specific gravity or apparent density and between fiber lumen diameter with specific gravity, total longitudinal shrinkage and with modulus of rupture in static bending.

Tree planting with drought tolerant species, particularly Acacia and Eucalyptus species may be considered as a logical method for rehabilitation of marginal lands which can potentially meet the needs of local people in terms of wood, fuel wood, fodder, edible fruits, etc. These goals may be much better attained when the trees are planted in floodwater spreading (FWS) systems which drastically change the desert ecosystems through provision of more water and better rooting environments. In 1994, a pilot project was carried out in FWS systems in Gareh Baygan Plain in Fars Province of Iran to study the growth and performance of four Eucalyptus and four Acacia species which had previously been tested successfully in a preliminary adaptation experiment. A randomized complete block design with four replications was employed to establish the experiment. Each replication comprised of eight plots (species) and each plot contained 49 trees with 3m×3m spacing. The seedlings were irrigated only by rain and ephemeral floodwaters. In a ten year period, growth parameters including survival percentage, height and diameter at breast height were assessed or measured every year. The existence of pests or diseases and the viability of the trees were also monitored annually and the final evaluation was made at the age of ten. Survival and growth performance of the trees were quite satisfactory. Eucalyptus camaldulensis, E. oleosa, Acacia victoriae, A. salicina, and E. microtheca were all promising species, showing over eighty percent survival in the final year of experiment and were not significantly different from each other. The survival of E. fruticetorum was significantly different (p=0.0001) from those of the other species. Eucalyptus camaldulensis showed the highest growth in terms of height and diameter, while A. saligna ranked the lowest. It may be concluded that E. camaldulensis, E. oleosa, E. microtheca, E. fruticetorum, A. salicina, and A. victoriae were highly promising species and may be recommended for large-scale plantations in arid zones of southern Iran, using floodwater spreading systems. Moreover, further tests of cold resistant provenances of A. cyanophylla and A. saligna are recommended.

The objectives of the present work were to establish the minimal lethal dose of the selective agent to determine the type and concentration of appropriate antibiotics for the elimination of Agrobacterium tumefaciens inoculated explants, without interfering with the regenerative potential of the E. camaldulensis cotyledonary explants. Non-transformed explants were cultivated in medium supplemented with kanamycin. The results showed that the antibiotic was suitable for the selection of transformed cells in the concentration of 9 mg L-1 as it inhibited the growth of non-transformed cells. Cotyledons infected with A. tumefaciens were cultivated in MS N/2 medium supplemented with BAP, ANA, Km and cefotaxime or AugmentinÒ . The highest average of regenerated shoots by explant (5,4) was observed in the presence of 300 mg L-1 of AugmentinÒ /15 days, followed by 150 mg L-1/15 days and 100 mg L-1/30 days.O presente trabalho teve como objetivos determinar o tipo e a concentração de antibióticos adequados para a eliminação de Agrobacterium tumefaciens de explantes inoculados e estabelecer a dose letal mínima do agente seletivo canamicina (Km), sem interferir com o potencial regenerativo do explante cotiledonar de E. camaldulensis. Para a avaliação da eficiência dos antibióticos, cotilédones infectados com A. tumefaciens foram cultivados em meio MS N/2 com BAP, ANA, canamicina e cefotaxima ou AugmentinaÒ . Foi observada a maior média de brotos regenerados por explante (5,4) na presença de 300 mg.L-1 de AugmentinaÒ /15 dias, seguido por 150 mg.L-1/30 dias, e 100 mg.L-1/30 dias. Explantes cotiledonares não transformados foram cultivados em meio de cultura suplementado com antibiótico canamicina onde a concentração adequada para a seleção de células transformadas foi de 9 mg.L-1.

A considerable portion of Brazil‘s commercial eucalypt plantations is located in areas subjected to periods of water deficit and grown in soils with low natural fertility, particularly poor in potassium. Potassium is influential in controlling water relations of plants. The objective of this study was to verify the influence of potassium fertilization and soil water potential (Ψw) on the dry matter production and on water relations of eucalypt seedlings grown under greenhouse conditions. The experimental units were arranged in 4x4x2 randomized blocks factorial design, as follow: four species of Eucalyptus (Eucalyptus grandis, Eucalyptus urophylla, Eucalyptus camaldulensis and hybrid Eucalyptus grandis x Eucalyptus urophylla), four dosages of K (0, 50, 100 and 200 mg dm-3) and two soil water potentials (-0.01MPa and -0.1 MPa). Plastic containers with 15 cm diameter and 18 cm height, with Styrofoam base, containing 3.0 dm3 of soil and two plants per container were used. Soil water potential was kept at –0.01MPa for 40 days after seeding. Afterward, the experimental units were divided into two groups: in one group the potential was kept at -0.01MPa, and in the other one, at -0.10 MPa. Soil water potential was controlled gravimetrically twice a day with water replacement until the desired potential was reestablished. A week before harvesting, the leaf water potential (Ψ), the photosynthetic rate (A), the stomatal conductance (gs) and the transpiration rate were evaluated. The last week before harvesting, the mass of the containers was recorded daily before watering to determine the consumption of water by the plants. After harvesting, total dry matter and leaf area were evaluated. The data were submitted to analysis of variance, to Tukey's tests and regression analyses. The application of K influenced A, gs and the transpiration rate. Plants deficient in K showed lower A and higher gs and transpiration rates. There were no statistical differences in A, gs and transpiration rates in plants with and without water deficit. The addition of K reduced the consumption of water per unit of leaf area and, in general, plants submitted to water deficit presented a lower consumption of water.

O trabalho teve como objetivo avaliar a sobrevivência do clone H13 de Eucalyptus urograndis sob dois manejos hídricos de viveiro, plantados em dois solos, com e sem a adição de polímero hidroabsorvente (hidrogel). O plantio foi realizado em vasos mantidos em estufa, com dois tipos de solo: um arenoso e outro argiloso. Cada vaso recebeu 2,5 L de solo, um litro de água e o hidrogel na proporção de 0,4 g vaso-1 (120 mL de gel). O delineamento experimental adotado foi o inteiramente casualizado, com três repetições. Os sintomas de estresse, nos vários níveis avaliados, sempre se manifestaram primeiro nas plantas no solo argiloso, de modo mais acentuado naquelas que foram mantidas sem estresse de água na fase de viveiro. Isso garantiu que as plantas sobrevivessem por um período menor sem água, variando de 14 a 20 dias (com e sem hidrogel, respectivamente), enquanto, no solo arenoso, a sobrevivência foi maior, de 29 a 34 dias (com e sem hidrogel, respectivamente). Apesar da não significância estatística, os resultados com o hidrogel possibilitam, em ambos os solos, maior flexibilidade operacional na intervenção com novas irrigações.The research aim was to evaluate the survival of Eucalyptus urograndis clone H13 selected for water deficit, under two water management for nursery, with and without the addition of hydro absorbent polymers (hydrogel), planted in two soils. The plantation was done in vases kept in greenhouse with two different soil textures: sandy and clay. Each vase received 2.5 L of soil, one liter of water and 0.4 g (120 mL of polymer) of hydro absorbent polymers. The experimental delineation was totally randomized, with three repetitions. The water deficit symptoms at different levels always appeared first in plants of vases with clay soil, starting in those that were kept without water stress in the nursery phase. Assuring the plants survival in a period without water varying from 14 to 20 days (with and without hydrogel, respectively), while for sandy soil, plants survived from 29 to 34 days (with and without hydrogel, respectively). Despite no statistically significant results with the hydrogel, it allows great operational flexibility for intervention with new irrigation in both soils.

O conhecimento detalhado de radiação solar total que incide sobre uma região é importante para o planejamento das atividades florestais. Poucos trabalhos têm considerado a topologia da região para determinar o saldo de radiação solar (Rn), o que pode levar a erros significativos de estimativa dessa variável, dependendo do tipo de relevo predominante na região. Este estudo teve como objetivo estimar o Rn em plantios de eucalipto, levando-se em consideração a exposição do terreno em plantios florestais de eucalipto, bem como comparar essas estimativas com a estimativa em condições de topografia plana. A simulação foi realizada para os anos de 2001 e 2002, em uma microbacia do rio Doce. As encostas com orientações para o norte, nordeste e noroeste apresentaram aumentos do Rn em relação à estimativa da superfície plana, pelo fato de que, nessa época do ano, o sol, em seu movimento aparente, encontra-se ao norte da microbacia. Entretanto, as encostas com orientações para o sul, sudeste e sudoeste tiveram diminuição do Rn quando comparadas com as condições de topografia plana. A inclinação das encostas influenciou a magnitude das diferenças de ganho e perda de Rn. Quanto maiores as inclinações das encostas voltadas para o norte, noroeste e nordeste, maiores as variações, atingindo valores percentuais de aumento do Rn de até 40%, em julho. Portanto, verificou-se existir importante influência das diferentes inclinações e orientações das encostas nos totais diários do Rn.The detailed knowledge of the total solar radiation that reaches a surface is fundamental for the planning of the forest activities. A few research works cited in the literature have considered the topographic effect of the region to determine the solar radiation balance (Rn), in which, depending on the predominant topographic relief of the region, significant errors can be obtained. This study was carried out to estimate the Rn considering the slope aspect of the terrain for eucalypt forest plantation, and to compare this estimates with and flat terrain areas. The simulation was carried out for the years of 2001 and 2002 in Rio Doce watershed. The hillsides with northward, northeast and the northwest orientation presented increases in Rn in relation to the estimate for flat horizontal surface, because at this time of the year, the sun, in its apparent movement, tape place north of the watershed. However, the hillsides with south, southeast and southwest orientation, presented reduction in Rn when compared with the conditions of flat topography. The hillsides inclination influenced in the magnitude of the differences between gain of energies and loss Rn. The hillsides inclinations faced northward, the northwest and northeast, had greaters variations, witch increased Rn of up to 40%, in July. It was demonstrated that exist important influence of the different slopes and aspects of the hillsides terrain over the total daily radiation balance.

This work aimed to analyze the socio-economic reorganization due to the insertion of Eucalyptusplantation (Eucalyptus grandis) in the far southern region of Bahia. In order to accomplish this analysis,it was done a diagnosis of the main social and economical changes due to the establishment of eucalyptusin the region, using literature retrieval, IBGE’s socio-economic data and the UNDP’s Atlas of HumanDevelopment. It could be noted that the insertion of Eucalyptus plantation in the region has provokeda significant growth of Bahia’s exports participation in the national scenario, making the economymore dynamic, especially in the far southern region of Bahia. This impact in the economy may beperceived through the GDP’s rising in the State level as far as in the counties that grow eucalyptusgrandis. In relation to the rural landscape, it was noted a considerable changing related to a reductionin the number of the agricultural activities and to the land concentration. It defines a reforming frameworkof the local land ownership structure. Under this new agricultural scenario, it can be noted, for instance,the reduction concerning the number of jobs generated in the rural area, and the activities developed inthe context of the family agriculture; what provokes an increasing of urban population.

Neste trabalho, estudaram-se o desenvolvimento e a reprodução de Dirphia moderata Bouvier, 1919 (Lepidoptera: Saturniidae) alimentada com Eucalyptus cloeziana F. Muell ou Psidium guajava L. Os períodos de pré-oviposição, oviposição e incubação e a viabilidade e número de ovos por fêmea foram de 6,71 ± 0,18 dia; 4,00 ± 0,66 dia; 18,14 ± 0,18 dia; 17,54 ± 3,78%; 121,71 ± 18,96% para esse inseto com E. cloeziana e de 3,86 ± 0,26 dia; 5,86 ± 0,40 dia; 17,71 ± 0,21 dia; 23,12 ± 10,81%; 112,00 ± 8,79% com P. guajava, respectivamente. A duração e viabilidade larval (%) foram de 53,00 ± 0,09 e 80,00 ± 0,99 e de 55,83 ± 0,29 e de 77,5 ± 6,60 para lagartas de D. moderata criadas nos primeiro e segundo hospedeiros, respectivamente. A duração e viabilidade das fases de pré-pupa e pupa foram de 4,84 ± 0,07 dia e 96,88 ± 3,13% e de 37,64 ± 1,20 dia e 84,37 ± 6,53% com E. cloeziana e de 3,82 ± 0,06 dia e 100% e de 49,93 ± 2,04 dias e 75,00 ± 7,79% com P. guajava, respectivamente. A razão sexual de D. moderata foi de 0,48 e 0,46 e a longevidade, de 6,78 e 8,84 dias para machos e de 10,23 e 10,07 dias para fêmeas desse inseto com E. cloeziana e P. guajava, respectivamente. D. moderata apresentou melhor desenvolvimento e reprodução em E. cloeziana, mas P. guajava pode, também, ser utilizado para a criação desse inseto em laboratório.This work studied the development and reproduction of Dirphia moderata Bouvier, 1919 (Lepidoptera: Saturniidae) fed on Eucalyptus cloeziana F. Muell or Psidium guajava L. The periods of pre-oviposition, oviposition and egg incubation as well as viability and number of eggs per female were 6.71 ± 0.18 days; 4.00 ± 0.66 days; 18.14 ± 0.18 days; 17.54 ± 3.78%; 121.71 ± 18.96 for this insect on E. cloeziana and 3.86 ± 0.26 days; 5.86 ± 0.40 days; 17.71 ± 0.21 days; 23.12 ± 10.81%; 112.00 ± 8.79 on P. guajava, respectively. Larva stage duration and viability (%) were 53.00 ± 0.09 and 80.00 ± 0.99 and 55.83 ± 0.29 and 77.5 ± 6.60 for caterpillars of D. moderata reared with the first and second hosts, respectively. Duration and viability of the pre-pupa and pupa stages were 4.84 ± 0.07 days and 96.88 ± 3.13% and 37.64 ± 1.20 days and 84.37 ± 6.53% on E. cloeziana and 3.82 ± 0.06 days and 100.00% and 49.93 ± 2.04 days and 75.00 ± 7.79% on P. guajava, respectively. Sex rate of D. moderata was 0.48 and 0.46 and longevity was 6.78 and 8.84 days for males and 10.23 and 10.07 days for females when this insect fed on E. cloeziana and P. guajava, respectively. Dirphia moderata presented better development and reproduction with E. cloeziana but P. guajava can also be used to rear this insect in the laboratory.

Este estudo teve como objetivo predizer a produção volumétrica e o estoque de carbono nos fustes das árvores em povoamentos de eucalipto, bem como avaliar economicamente a inclusão dos Certificados de Emissões Reduzidas (CERs) nos projetos florestais através de critérios quantitativos. Para isso, utilizaram-se dados de povoamentos de Eucalyptus grandis localizados no Município de Guanhães, MG, Minas Gerais. De posse das equações de volume e carbono para o fuste das árvores individuais e de 95 parcelas permanentes, ajustou-se o modelo de crescimento e produção de Clutter (1983) para projeção da produção volumétrica e do estoque de carbono. Após as análises, verificou-se que: a) o modelo de crescimento e produção proposto por Clutter (1983) propiciou idades técnicas de colheita coerentes com a capacidade produtiva dos povoamentos, tanto para a produção volumétrica quanto para o estoque de carbono; b) as idades técnicas de colheita (ITCs) foram praticamente iguais, considerando-se o estoque volumétrico e o estoque de carbono; c) as rotações econômicas foram maiores do que as idades técnicas de colheita (ITCs) em locais de baixa e média produtividades (S = 20 e S = 26), independentemente da inclusão ou não dos CERs; d) os CERs contribuem para a viabilidade financeira dos projetos florestais em locais de baixa produtividade, quando se considera que as receitas sejam auferidas no ano de implantação do projeto; e) na análise de sensibilidade, o preço da madeira foi o item que mais influenciou a viabilidade econômica dos projetos. No entanto, os Certificados de Emissões Reduzidas tiveram pouca influência.The objectives of this study were to predict volumetric yield and carbon stock in the stems of eucalypt plantation trees, as well as to economically evaluate the inclusion of the Reduced Emission Certificates (RECs) in forest projects by quantitative criteria. Thus, data from Eucalyptus grandis stands, located in Guanhães-Minas Gerais, were used. Based on the volume and carbon equations for the stems of individual trees and for 95 permanent plots, Clutter growth and production model (1983) were adjusted for volumetric production and carbon stock projection. After analysis, it was verified that: a) the growth and yield model proposed by Clutter (1983) provided technical cutting ages according to the productivity capacity of the stands, both for volumetric yield and carbon stock; b) the technical cutting ages (TCAs) were practically the same, considering the volumetric and carbon stocks; c) the economic rotations were greater than the technical cutting age in sites with low and average productivity (S = 20 and S = 26), regardless of the inclusion or not of the CERs in the analysis; d) the CERs contributed to the economic viability of the forest projects in low productivity sites, considering the budgets for the establishment of the projects; e) in the sensitivity analysis, the item wood price had the greatest influence on the economic viability of the projects. In contrast, the Reduced Emission Certificates (RECs) had little influence.

O psilídeo-de-concha, Glycaspis brimblecombei, é uma praga exótica específica de Eucalyptus, que causa desfolha, secamento de ponteiros e ramos, podendo levar as árvores à morte. O parasitóide Psyllaephagus bliteus é indicado como principal agente no controle biológico desta praga. Portanto, o monitoramento adequado de as ambas espécies por um método eficiente de amostragem facilitaria o manejo para uma futura tomada de decisão. Devido à falta de informações referentes ao seu comportamento em plantações extensivas de eucalipto no Brasil, este trabalho teve como objetivo estudar as populações de G. brimblecombei e de P. bliteus em florestas de Eucalyptus camaldulensis, utilizando armadilhas amarelas para determinação de sua flutuação populacional e correlacionado-as com variáveis meteorológicas (temperatura e precipitação). A determinação da flutuação populacional (53 pontos amostrais) foi realizada em talhão de 19ha com E. camaldulensis em Luíz Antônio, SP, em 10avaliações quinzenais, entre janeiro e junho de 2005. As populações de ambas as espécies apresentaram correlação inversamente proporcional em função da temperatura e não há correlação com a precipitação no período avaliado.Psyllids are one most widespread group of pests, causing severe damage on agricultural and forestry systems. The recently discover about occurrence of red gum lerp psyllid Glycaspis brimblecombei Moore (Hemiptera: Psyllidae), in Brazil is, nowadays a serious problem in Eucalyptus forests, mainly in E. camaldulensis. The psyllid specific parasitic wasp Psyllaephagus bliteus Riek (Hymenoptera: Encyrtidae) is the main biological control agent of this pest. Thus, the adequate monitoring of both species by efficient sampling method would facilitate a future decision making. Due to economic importance, this study aimed to evaluate G. brimblecombei and P. bliteus populations in Eucalyptus camaldulensis plantation, using yellow traps to determinate population fluctuation with weather interactions (temperature and rainfall). The study of the pest and parasitoid population (53 sampling dates) was carried out on E. camaldulensis plantations in 19ha area in Luíz Antônio municipality (SP, Brazil), with quarterly samplings, between January and June, 2005 (ten sampling dates). This research indicated that populations had an inversely proportional correlation subject according to the temperature. However, there is no correlation between both species with the rainfall in the evaluated period.