Cuticular Hydrocarbons of Heterotermes tenuis (Isoptera: Rhinotermitidae): Analyses and Electrophysiological Studies

Termites have become an important pest of Eucalyptus and Pinus reforestations, sugarcane and other cultures. An alternative for the control of this pest would be the use of attractive traps that take in account the social behavior of these insects. Diverse factors are important for the insects in the localization of the habitat and the choice of the food and specific odors can facilitate this. Studies referring to Heterotermes tenuis (Isoptera: Rhinotermitidae) are scarce. The objective of this work was to analyze the tergal cuticular extract of H. tenuis and determine the selectivity and sensitivity of its antennae to the components of this extract by electroantennography (EAG). The composition of the cuticular extract was determined by GC-MS analysis. The hydrocarbons found were restricted to linear alkanes, being most abundant C24 to C27 that comprises ca. 65% of the total. Olefins were not detected. EAG and behavioral test responses to the cuticular hydrocarbons were greater and significantly different from the control and the high selectivity of the antennae to the extract indicates its potential as chemical messenger. Cuticular hydrocarbons mixture is species-specific and can be used to identify a given taxon without the diagnostic castes, soldiers or imagoes. Difference in the composition appears to relate with the type of habitat of specie.

Electroantennographic responses of Heterotermes tenuis (Isoptera: Rhinotermitidae) to synthetic (3Z,6Z,8E)-Dodecatrien-1-ol

The subterranean termite Heterotermes tenuis (Isoptera: Rhinotermitidae) is a pest of great importance for the Brazilian economy as it causes serious damages in commercial reforestations of Eucalyptus spp. and sugarcane cultures. (3Z,6Z,8E)-Dodecatrien-1-ol has been identified as a pheromone of some species of subterranean termites. The objective of this research was to synthesize (3Z,6Z,8E)-dodecatrien-1-ol and determine by electroantennographic (EAG) bioassays the selectivity and sensitivity of H. tenius antennae to its whole worker extract and to the synthetic triene alcohol.

Parâmetros genéticos para caracteres de crescimento, de produção e tecnológicos da madeira em clones de Eucalyptus spp

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Efeitos da irrigação na sobrevivência, transpiração e no teor relative de água na folha em mudas de Eucalyptus grandis em diferentes substratos

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Mensuração do comprimento das fibras para a determinação da madeira juvenil em Eucalyptus citriodora

The juvenile wood has peculiar characteristics from the anatomical structure and physical-mechanical properties, considering these aspects the knowledge of the wood is essential for wood adequate utilization. The aim of this work was to determinate the zone of juvenile wood of pith-bark direction in Eucalyptus citriodora. The juvenile and mature wood zones were determined across fiber length measurement in various height in the tree stem. Results showed that juvenile wood zone occurs approximately up to the 45 at 55 mm from the pith.

Comportamento fisiológico e morfológico de clones de Eucalyptus urograndis submetidos a diferentes níveis de água no solo

The present study had as its objective the assessment of the possible effects of hydric stress on the growth, physiological characteristics of two different genetic materials from Eucalyptus urograndis. The experiment was carried out in a greenhouse at Faculdade de Ciências Agronômicas of UNESP, campus Botucatu from March to July, 2005. The hydric management was established based on the soil water potential. Two water levels were established, doing the evapotranspired water replacement by pot weighing. Two clones were used, Eucalyptus urograndis 105 and 433, being the first one more resistant to the hydric deficit and the 433 more sensitive to stress. The study was made from a 2×2 factorial (two levels of water × two genetic materials). For the hydric management, the plants were irrigated when they reached a soil water potential of -0.03 MPa or -1.5 MPa. The assessments made were: diffusive water vapor of stomato, transpiration, leaf temperature and leaf water potential. The physiological evaluations throughout the day, in the end of the experiment. Treatments without hydric stress had a higher performance in all studied characteristics, but the clones had no influence. The stomatic resistance followed the potentials, showing higher values in the treatments submitted to hydric deficiency, more intensely for clone 433, being that this also happened with the leaf water potential. The transpiration also followed the leaf water potential and the stomatic resistance more intensely for clone 105 both comparing stressed plants and non-stressed plants. Consequently, the leaf temperatures had higher values for clone 433 on the stressed treatment. Thus, it can be concluded that there was a better performance in plants kept on a soil water potential of -0.03 MPa and a higher resistance to hydric stress for clone 105.

In vitro cytotoxic and non-genotoxic effects of gutta-percha solvents on mouse lymphoma cells by single cell gel (comet) assay

Chloroform and eucalyptol are widely used in clinical dentistry as gutta-percha solvents. However, these compounds may represent a hazard to human health, especially by causing injury to genetic apparatus and/or inducing cellular death. In this study, the genotoxic and cytotoxic potentials associated with exposure to chloroform and eucalyptol were assessed on mouse lymphoma cells in vitro by the single cell gel (comet) assay and trypan blue exclusion test, respectively. Both gutta-percha solvents proved to be cytotoxic at the same levels in concentrations of 2.5, 5 and 10 μL/mL (p<0.05). On the other hand, neither of the solvents induced DNA breakage. Taken together, these results suggest that although both tested compounds (chloroform and eucalyptol) are strong cytotoxicants, it seems that they are not likely to increase the level of DNA damage on mammalian cells.

Influência da posição diametral das tábuas e da vaporização nos defeitos de secagem de Eucalyptus grandis

This study evaluated the Eucalyptus grandis drying defects acting on boards diametrical position and on log steaming. Half of the logs, with diameter from 20 to <25, 25 to <30 and 30 to <35cm, were steamed during 20 hours at 90°C of temperature. Subsequently, the logs (control and steamed) were sawn. The boards were dried in the dry-kiln pilot and the resulting defects from the drying process were measured. The results indicate that: (1) the boards coming from control logs presented different magnitude defects in function of the diametrical position. The split and spring to increase in direction to pith, the bow to increase in direction to bark and cupping were bigger in intermediary boards; (2) the boards coming from steamed logs presented a reduction from drying defects in function of logs diameter and its more homogeneous index in the pith-bark direction.

Desenvolvimentos da biopolpação no Brasil

Biopulping is a technology which application can be advantageous to mechanical or chemical pulping. It presents benefits such as the creation of stronger pulp, as well as energy or chemicals savings. This paper gives an overview of the recent efforts to develop biopulping processes in Brazil as well as provides critical information on biopulping development worldwide. Eucalyptus grandis wood chips have been biotreated by Ceriporiopsis subvermispora in a 50-ton biopulping pilot-plant and used to produce TMP and CTMP pulps on a mill scale, Up to 18% and 27% energy savings have been observed for producing 450-470 CSFreeness TMP and CTMP pulps. Despite darker bio-TMP pulps are produced, one-stage bleaching with 5% H2O2 was sufficient to improve brightness values to 70% and 72% for bio-TMP and control pulps, respectively. Understanding biopulping mechanisms is also relevant because more resistant and competitive fungal species could be selected with basis on a function-directed screen-ing project. As far as the chemical changes induced by the fungus in wood are concerned, recent efforts have pointed out for two different types of wood transformations. One of them involves intense lignin depolymerization in short biotreatment periods, while the other indicates that esterification reactions of oxalate secreted by the Jungas on the polysaccharides chains increase the water saturation point of the fibers. Both transformations are expected to affect the fiber-fiber bonding and, consequently, the physical resistance of wood.

Efeito do alumínio no conteúdo de poliaminas livres e atividade da fosfatase ácida durante o crescimento de brotações de Eucalyptus grandis × E. urophylla cultivadas in vitro

This paper is aiming to evaluate the effects of different levels of the aluminum on the growth of the Eucalyptus grandis x E. urophylla shoots cultivated in vitro. Evaluations were carried out on pH and chemicals modifications of the culture medium by Geochem program, polyamines contents (putrescine, espermidine e espermine) and acid phosphatase ativity on the shoots. The trial had a totally randomized design with four treatments and four replicates. The treatments were: 0.0, 6.75,13.50 and 27 mg.L -1 of AlCl 3.6H 2. Evaluations were carried out on the 4th, 8th, 12th, 16th, 20th, 24th and 28th day of culture. The addition of the aluminium, in all concentrations, affected the culture medium ionic equilibrium, the morphology of the shoots, reduced the pH on the medium, induced an increase in polyamines content and higher acid phosphatase activity.

Influência de solos de diferentes texturas no desenvolvimento de plantas de Eucalyptus urograndis submetidas a déficit hídrico

The studies were developed with plants of Eucalyptus urograndis under greenhouse conditions, at Paulista State University (UNESP), Botucatu - SP, from March to July, 2005. The objective was to evaluate hydric stress influence on morphological and physiological characteristics of plants in clayay (1) and medium (2) soil texture. Two water treatment were used: -0.03 and -1.5 MPa minimum soil water potentials (□w). Plants from soil 2 and - 1.5MPa showed 43% reduction on leaf área, 34% on base stem diameter, 54% on aerial vegetal dry matter and plants from soil 1 presented 42.3% reduction on leaf área, 39,5% base stem diameter and 42% dry matter root reduction in relation to -0.03 MPa. The lowest leaf water potential (□f) value was-17.166 MPa on □w = -1.5 MPa and soil 2 and the greatest one on soil 1 and □w = -0.03 MPa., -6.766 MPa. The treatment -0.03MPa showed about 11,3% higher transpiration values than those plants from -1.5MPa. The higher Rs value (2.149 s.cm-1) occurred on plants under -1.5MPa and soil 2. There was significant correlation between Tf and Rs, and the treatmens from medium soil were more sensitive, reaching until 32°C.

Energia de briquetes produzidos com rejeitos de resíduos sólidos urbanos e madeira de Eucalyptus grandis

The incentive for consumption and production in large quantity in modern society generates enormous amounts of urban solid residues in the form of municipal solid waste (MSW). With the intention of reducing these residues of the municipal waste tips and to generate energy, briquettes with mixtures of MSW and residues of Eucalyptus grandis were produced. The briquettes were manufactured with 0, 5, 10, 15, 20 and 25% of MSW in the mixture with wood waste and 12% of moisture content. The analyzed parameters used to choose the best treatments were combustion analysis versus ash content, mechanical strength and energy content. The briquettes up to 10% of MSW showed low resistance, and above 15% showed large increase in ash content. Therefore, the treatment that fulfilled the requirements for combustion versus ash content and mechanical resistance was of at least 15% of MSW, since the source of the ash is unidentified. Considering the net energy content, the best treatment was 25% of MSW, with 17,175 kJ kg-1. Nevertheless, it is strongly advised that further studies related to gas emissions are necessary.

Alternative to peat for Agaricus brasiliensis yield

Casing layer is one of the most important components of Agaricus spp. production and it directly affects mushroom productivity, size and mass. The aim of this study was to evaluate potential raw materials as a casing layer and their effect on Agaricus brasiliensis productivity. Raw materials from Brazil with potential use were selected and characterized, and the most promising ones were tested as casing layers for mushroom yield. Evaluated raw materials included lime schist, vermiculite, eucalyptus sawdust, sand, São Paulo peat, Santa Catarina peat, subsoil and charcoal. Particle size, porosity and water absorption in relation to mushroom yield for casing layers were determined. Lime schist, an alternate casing layer to peat, is presented and the effects of the casing layer on the mushroom yield are discussed. © 2009 Elsevier Ltd. All rights reserved.

Solvent capacity of different substances on gutta-percha and resilon

The aim of this study was to evaluate the effectiveness of 3 solvents (eucalyptol, orange oil, and xylol) on 2 types of gutta-percha (conventional and thermoplastic) and Resilon. Specimens (10 mm diameter × 1 mm thick; n=7 per condition) were prepared and maintained at 37°C for 48 h. Each specimen was weighed on a precision scale every 24 h until its mass was stable, at which time the initial mass was determined. Specimens (n=7) were then immersed in the solvent solutions and, after 48 h at 37°C, they were reweighed at 24- h intervals, until stabilization (final mass). The difference between the final and the initial mass determined the solvent capacity of each solvent. Data were subjected to analysis of variance and Tukey's test at 5% significance level. The results demonstrated that xylol was the most effective, especially on conventional gutta-percha and Resilon (p<0.05). Eucalyptol and orange oil were more effective on thermoplastic gutta-percha than the other materials (p<0.05). It was concluded that all evaluated substances presented solvent action, but xylol was the most effective on both gutta-percha or Resilon.

Respostas de clones de Eucalyptus grandis e E. grandis x E. urophylla à supressão de boro

The present work had as objective the study of clones of Eucalyptus grandis and E. grandis × E. urophylla under boron suppression on growth in height and diameter, development of symptoms of deficiency, boron content in leaf and polyols production. Plants were cultivated in pots with quartz in a greenhouse using two levels of boron per solution (0 and 0.5 mg L-1 of B). The 32 treatments followed a factorial scheme: 16 × 2 -16 clones and two doses of boron in a randomized block experimental design, with fve repetitions, totaling 160 plots. Plants were evaluated weekly for deficiency symptoms and monthly for height, stem diameter and leaf content of boron in different plant parts. The content of polyols was measured in two occasions: at 162 days and 192 days after starting the experiment. Decrease of growth and quick development of deficiency symptoms 40 days after boron suppression were observed, as well as a decrease of polyols synthesis. Foliar analysis, with boron supplement, resulted in the presence of mannitol and sorbitol in high enough concentration so that the evaluated plants could be considered rich in those polyols. Under boron suppression, boron levels in different portions of branches and stems of plants, as well as the presence of mannitol and sorbitol, indicated a conditional mobility of boron in Eucalyptus.