964 resultados para ROOTING AND CLONAL FORESTRY


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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The present study evaluated the main physical and chemical characteristics of Syrah grapes, coming from the tropical region of São Francisco river valley, harvested at different times and their relationship with analytical characteristics of resulting wines. Grapes came from the first half of 2009 harvest, collected at Casa Nova - Bahia, a semi-arid and hot region, comprising an interval from 84 days after pruning (84 dap) to the beginning of grape over-ripening, 133 days after pruning (133 dap). Harvests at 84, 91, 98, 105, 112, 119, 126 and 133 dap, were analyzed for pH, soluble solids and acidity in grapes, which were then processed for wine production. Maximum sugar/acidity ratio (s/a = 56) were observed in grapes harvested between 126 and 133 dap, coincided with the highest concentration of anthocyanins (851 mg L-1 ) and total tannins (2.6 g L-1 ) in the resulting wines, indicating that grapes collected between 126 and 133 dap showed the best potential for winemaking in the tropical climate of São Francisco river valley. This result was confirmed by the analytical characterization of wines, that, between 126 and 133 dap, showed 12.8% alcohol, 31 g L-1 dry extract, 5.6 g L-1 ashes and a TPI of 58, using only one pumping per day, for 5 days maceration. Syrah grapes considered in the present work presented a good evolution of maturation, and grapes harvested between 126 and 133 days after pruning, showed the best oenological potential for the development of red wine. The use of pH and soluble solids appeared useful parameters in the estimation of maturation degree and quality potential of grapes for winemaking.

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This is the first report on the parasitoid Palmistichus elaeisis, genus Eulophidae, found in the field parasitizing pupae of defoliating eucalyptus. Lepidopterous pests occur in eucalyptus plantations in Brazil, reaching high population levels. Due to the complexity of pest control in eucalyptus forests, alternative control methods have been proposed, for instance biological control through use of parasitoids. Natural enemies play an important role in regulating host populations because their larvae feed on the eggs, larvae, pupae or adults of other insects. The parasitic Hymenoptera are important agents in biological control programs against forest pests, and may provide economic and environmental benefits. The generalist endoparasitoid Palmistichus elaeisis Delvare and LaSalle, 1993 (Hymenoptera: Eulophidae) can develop in its host’s pupae, which overcome the host’s physiology and can therefore be used for biological control of agricultural and forest pests. This study aimed to evaluate the impact of P. elaeisis as a pupal parasitoid of S. violascens in providing a potential alternative to chemical control of the pest and creation of an alternative host. The experiment was developed in the Laboratory for Biological Control of Forest Pests, Universidade Estadual Paulista "Julio Mesquita Filho”. Parasitoids used in this test were originally collected on pupae of E. eucerus. (Lepidoptera: Riodinidae) in eucalyptus plantations at Lençois Paulistas, São Paulo state, Brazil, in 2011. Thereafter, a laboratory culture has been maintained, using pupae of Spodoptera frugiperda (J. E. Smith) (Lep.: Noctuidae) as hosts. S. violascens eggs were collected in a eucalyptus clonal plantation in Sao Paulo state (Brazil). Larvae were reared under ambient conditions on Eucalyptus urophylla S.T. Blake (Myrtaceae) leaves. The following parameters were determined: parasitism level, numbers of emerged and non-emerged parasitoids and duration of egg-adult cycle. The S. violascens pupae were dissected to evaluate the non-emerged parasitoids. The parasitism level reached 100%, with a 100% emergence rate. It was verified that 113.2±0.8 parasitoids emerged per individual pupa versus only 0.7±0.1 that did not emerge. The P. elaeisis egg-adult cycle was 20.3±0.6 days in S. violascens pupae. This opens new perspectives for utilizing this parasitoid in biological control programs against caterpillars important to forestry. Sarsina violascens in Brazil.

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Understanding the geographic and environmental characteristics of islands that affect aspects of biodiversity is a major theme in ecology (Begon et al. 2006; Krebs 2001) and biogeography (Cox and Moore 2000; Drakare et al. 2006; Lomolino et al. 2006). Such understanding has become particularly relevant over the past century because human activities on continents have fragmented natural landscapes, often creating islands of isolated habitat dispersed within a sea of land uses that include agriculture, forestry, and various degrees of urban and suburban development. The increasingly fragmented or islandlike structure of mainland habitats has critical ramifications to conservation biology, as it provides insights regarding the mechanisms leading to species persistence and loss. Consequently, the study of patterns and mechanisms associated with island biodiversity is of interest in its own right (Whittaker 1998; Williamson 1981), and may provide critical insights into mainland phenomena that otherwise could not be studied because of ethical, financial, or logistical considerations involved with the execution of large-scale manipulative experiments.

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ABSTRACT This long term study focuses on testing various hazelnut cultivars for yield, nut quality and disease resistance. There are various cultivars that are being tested for these desired traits but only the Grand Traverse and Skinner will be applicable for the results of this localized study. The desired traits of commercial nut production are best matched by these two cultivars. Results from previous harvests will be used to draw trends to recommend commercially functional cultivars in Eastern Nebraska.

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Eucalyptus plantations occupy almost 20 million ha worldwide and exceed 3.7 million ha in Brazil alone. Improved genetics and silviculture have led to as much as a three-fold increase in productivity in Eucalyptus plantations in Brazil and the large land area occupied by these highly productive ecosystems raises concern over their effect on local water supplies. As part of the Brazil Potential Productivity Project, we measured water use of Eucalyptus grandis x urophylla clones in rainfed and irrigated stands in two plantations differing in productivity. The Aracruz (lower productivity) site is located in the state of Espirito Santo and the Veracel (higher productivity) site in Bahia state. At each plantation, we measured stand water use using homemade sap flow sensors and a calibration curve using the clones and probes we utilized in the study. We also quantified changes in growth, leaf area and water use efficiency (the amount of wood produced per unit of water transpired). Measurements were conducted for 1 year during 2005 at Aracruz and from August through December 2005 at Veracel. Transpiration at both sites was high compared to other studies but annual estimates at Aracruz for the rainfed treatment compared well with a process model calibrated for the Aracruz site (within 10%). Annual water use at Aracruz was 1394 mm in rainfed treatments versus 1779 mm in irrigated treatments and accounted for approximately 67% and 58% of annual precipitation and irrigation inputs respectively. Increased water use in the irrigated stands at Aracruz was associated with higher sapwood area, leaf area index and transpiration per unit leaf area but there was no difference in the response of canopy conductance with air saturation deficit between treatments. Water use efficiency at the Aracruz site was also not influenced by irrigation and was similar to the rainfed treatment. During the period of overlapping measurements, the response to irrigation treatments at the more productive Veracel site was similar to Aracruz. Stand water use at the Veracel site totaled 975 mm and 1102 mm in rainfed and irrigated treatments during the 5-month measurement period respectively. Irrigated stands at Veracel also had higher leaf area with no difference in the response of canopy conductance with air saturation deficit between treatments. Water use efficiency was also unaffected by irrigation at Veracel. Results from this and other studies suggest that improved resource availability does not negatively impact water use efficiency but increased productivity of these plantations is associated with higher water use and should be given consideration during plantation management decision making processes aimed at increasing productivity. Published by Elsevier B.V.

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Clonal eucalyptus plantings have increased in recent years; however, some clones with high production characteristics have vegetative propagation problems because of weak root and aerial development. Endophytic microorganisms live inside healthy plants without causing any damage to their hosts and can be beneficial, acting as plant growth promoters. We isolated endophytic bacteria from eucalyptus plants and evaluated their potential in plant growth promotion of clonal plantlets of Eucalyptus urophylla x E. grandis, known as the hybrid, E. urograndis. Eighteen isolates of E. urograndis, clone 4622, were tested for plant growth promotion using the same clone. These isolates were also evaluated for indole acetic acid production and their potential for nitrogen fixation and phosphate solubilization. The isolates were identified by partial sequencing of 16S rRNA. Bacillus subtilis was the most prevalent species. Several Bacillus species, including B. licheniformis and B. subtilis, were found for the first time as endophytes of eucalyptus. Bacillus sp strain EUCB 10 significantly increased the growth of the root and aerial parts of eucalyptus plantlets under greenhouse conditions, during the summer and winter seasons.

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Endometriosis is a multifactorial gynecological disease characterized by the presence of functional endometrium-like tissue in ectopic sites. Several studies have focused on elucidating the immunological, endocrine, environmental and genetic factors involved in endometriosis. However, its pathogenesis is still unclear. High-resolution comparative genomic hybridization was applied to screen for genomic imbalances in laser microdissected stromal and epithelial cells from 20 endometriotic lesions and three samples of eutopic endometrium derived from eight patients. The expression of seven stemness-related markers (CD9, CD13, CD24, CD34, CD133, CD117/c-Kit and Oct-4) in endometrial tissue samples was evaluated by immunohistochemistry. Samples of eutopic endometrium showed normal genomic profiles. In ectopic tissues, an average of 68 genomic imbalances was detected per sample. DNA losses were more frequently detected and involved mainly 3p, 5q, 7p, 9p, 11q, 16q, 18q and 19q. Many of the genomic imbalances detected were common to endometriotic stroma and epithelia and also among different endometriotic sites from the same patient. These findings suggested a clonal origin of the endometriotic cells and the putative involvement of stem cells. Positive immunostaining for CD9, CD34, c-Kit and Oct-4 markers was detected in isolated epithelial and/or stromal cells in eutopic and ectopic endometrium in the majority of cases. The presence of shared genomic alterations in stromal and epithelial cells from different anatomical sites of the same patient and the expression of stemness-related markers suggested that endometriosis arises as a clonal proliferation with the putative involvement of stem cells.

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Litterfall and litter decomposition are vital processes in tropical forests because they regulate nutrient cycling. Nutrient cycling can be altered by forest fragmentation. The Atlantic Forest is one of the most threatened biomes in the world due to human occupation over the last 500 years. This scenario has resulted in fragments of different size, age and regeneration phase. To investigate differences in litterfall and leaf decomposition between forest successional phases, we compared six forest fragments at three different successional phases and an area of mature forest on the Atlantic Plateau of Sao Paulo, Brazil. We sampled litter monthly from November 2008 to October 2009. We used litterbags to calculate leaf decomposition rate of an exotic species, Tipuana tipu (Fabaceae), over the same period litter sampling was performed. Litterfall was higher in the earliest successional area. This pattern may be related to the structural properties of the forest fragments, especially the higher abundance of pioneer species, which have higher productivity and are typical of early successional areas. However, we have not found significant differences in the decomposition rates between the studied areas, which may be caused by rapid stabilization of the decomposition environment (combined effect of microclimatic conditions and the decomposers activities). This result indicates that the leaf decomposition process have already been restored to levels observed in mature forests after a few decades of regeneration, although litterfall has not been entirely restored. This study emphasizes the importance of secondary forests for restoration of ecosystem processes on a regional scale.

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Restinga (sandbank) areas are fragile environments, which have been subjected to anthropogenic pressures since the country colonization. So that mitigate actions can be taken, it must be developed studies to better understand the ecological processes in these environments. Thus, this study aims to quantify litter and nutrients devolution and litter decomposition in a periodically flooded forest in 'Restinga da Marambaia', Rio de Janeiro. In the study area 10 conic collectors and 30 litter bags were installed. The annual litter devolution was 7.64 Mg.ha(-1), and September was the highest contribution month. Nitrogen was the element returned to the soil to a higher amount (71.9 kg ha(-1) yr(-1)), followed by potassium (41.1 kg ha(-1) yr(-1)). Litter decomposition rate 0.0015 g g(-1) day(-1) and the half-life were 462 days. Potassium was the element that showed the highest losses in comparison to the others. Cellulose appeared as a major participant in the structure of leaf litter, followed by lignin, the latter being associated with the leathery texture of the leaves in this formation.

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One of the greatest challenges in urological oncology is renal cell carcinoma (RCC), which is the third leading cause of death in genitourinary cancers. RCCs are highly vascularized and respond positively to antiangiogenic therapy. Endostatin (ES) is a fragment of collagen XVIII that possesses antiangiogenic activity. In this study, we examined the potential of ES-based antiangiogenic therapy to activate tumor-associated endothelial cells in metastatic RCC (mRCC). Balb/c-bearing Renca cells were treated with NIH/3T3-LendSN or, as a control, with NIH/3T3-LXSN cells. The T-cell subsets and lymphocyte populations of tumors, mediastinal lymph nodes and the spleen were assessed by flow cytometry. The expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) was assessed by real-time PCR, flow cytometry and immunohistochemistry analysis. ES gene therapy led to an increase in the percentage of infiltrating CD4-interferon (IFN)-gamma cells (P<0.05), CD8-IFN-gamma cells (P<0.01) and CD49b-tumor necrosis factor-alpha cells (P<0.01). In addition, ES therapy caused an increase at the mRNA level of ICAM-1 (1.4-fold; P<0.01) and VCAM-1 (1.5-fold) (control vs treated group; P<0.001). Through flow cytometry, we found a significant increase in the CD34/ICAM-1 cells (8.1-fold; P<0.001) and CD34/VCAM-1 cells (1.6-fold; P<0.05). ES gene therapy induced a significant increase in both T CD4 and CD8 cells in the lymph nodes and the spleen, suggesting that ES therapy may facilitate cell survival or clonal expansion. CD49b cells were also present in increased quantities in all of these organs. In this study, we demonstrate an antitumor inflammatory effect of ES in an mRCC model, and this effect is mediated by an increase in ICAM-1 and VCAM-1 expression in tumor-associated endothelial cells.

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Tropical forests are experiencing an increase in the proportion of secondary forests as a result of the balance between the widespread harvesting of old-growth forests and the regeneration in abandoned areas. The impacts of such a process on biodiversity are poorly known and intensely debated. Recent reviews and multi-taxa studies indicate that species replacement in wildlife assemblages is a consistent pattern, sometimes stronger than changes in diversity, with a replacement from habitat generalists to old-growth specialists being commonly observed during tropical forest regeneration. However, the ecological drivers of such compositional changes are rarely investigated, despite its importance in assessing the conservation value of secondary forests, and to support and guide management techniques for restoration. By sampling 28 sites in a continuous Atlantic forest area in Southeastern Brazil, we assessed how important aspects of habitat structure and food resources for wildlife change across successional stages, and point out hypotheses on the implications of these changes for wildlife recovery. Old-growth areas presented a more complex structure at ground level (deeper leaf litter, and higher woody debris volume) and higher fruit availability from an understorey palm, whereas vegetation connectivity, ground-dwelling arthropod biomass, and total fruit availability were higher in earlier successional stages. From these results we hypothetize that generalist species adapted to fast population growth in resource-rich environments should proliferate and dominate earlier successional stages, while species with higher competitive ability in resource-limited environments, or those that depend on resources such as palm fruits, on higher complexity at the ground level, or on open space for flying, should dominate older-growth forests. Since the identification of the drivers of wildlife recovery is crucial for restoration strategies, it is important that future work test and further develop the proposed hypotheses. We also found structural and functional differences between old-growth forests and secondary forests with more than 80 years of regeneration, suggesting that restoration strategies may be crucial to recover structural and functional aspects expected to be important for wildlife in much altered ecosystems, such as the Brazilian Atlantic forest. (C) 2012 Elsevier B.V. All rights reserved.

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Introducing nitrogen-fixing tree species in fast-growing eucalypt plantations has the potential to improve soil nitrogen availability compared with eucalypt monocultures. Whether or not the changes in soil nutrient status and stand structure will lead to mixtures that out-yield monocultures depends on the balance between positive interactions and the negative effects of interspecific competition, and on their effect on carbon (C) uptake and partitioning. We used a C budget approach to quantify growth, C uptake and C partitioning in monocultures of Eucalyptus grandis (W. Hill ex Maiden) and Acacia mangium (Willd.) (treatments E100 and A100, respectively), and in a mixture at the same stocking density with the two species at a proportion of 1 : 1 (treatment MS). Allometric relationships established over the whole rotation, and measurements of soil CO2 efflux and aboveground litterfall for ages 4-6 years after planting were used to estimate aboveground net primary production (ANPP), total belowground carbon flux (TBCF) and gross primary production (GPP). We tested the hypotheses that (i) species differences for wood production between E. grandis and A. mangium monocultures were partly explained by different C partitioning strategies, and (ii) the observed lower wood production in the mixture compared with eucalypt monoculture was mostly explained by a lower partitioning aboveground. At the end of the rotation, total aboveground biomass was lowest in A100 (10.5 kg DM m(-2)), intermediate in MS (12.2 kg DM m(-2)) and highest in E100 (13.9 kg DM m(-2)). The results did not support our first hypothesis of contrasting C partitioning strategies between E. grandis and A. mangium monocultures: the 21% lower growth (delta B-w) in A100 compared with E100 was almost entirely explained by a 23% lower GPP, with little or no species difference in ratios such as TBCF/GPP, ANPP/TBCF, delta B-w/ANPP and delta B-w/GPP. In contrast, the 28% lower delta B-w in MS than in E100 was explained both by a 15% lower GPP and by a 15% lower fraction of GPP allocated to wood growth, thus partially supporting our second hypothesis: mixing the two species led to shifts in C allocations from above- to belowground, and from growth to litter production, for both species.