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The search for natural wood preservatives is becoming increasingly evident due to industrial preservatives presenting several environmental restrictions, such as soil, water and ecosystems contamination. Therefore, the objective of the present study is to evaluate the antifungal activity of Cinnamomum zeylanicum bark natural extract subjected to rotting fungi. In order to obtain the aqueous extract, two methods were performed with different concentrations, 50 and 100 g L-1, using Pycnoporus sanguineus e Gloeophyllum trabeum, mycelium. In the first, we kept the C. Zeylanicum bark with distilled water for 1 h in water bath and, in the second, the same concentrations were used, however, this was kept in a recipient for 24 h. Then, the extract was subjected to sterilization along with the BDA medium in autoclave at 120°C for 20 min, they were then put in petri dishes for later evaluation of the mycelium root growth compared with the control. The fungi Pycnoporus sanguineus presented higher fungal activity, obtaining total inhibition of all treatments and extract concentrations, however, for the fungi Gloeophyllum trabeum, the 100 g L-1 concentration warmed in water bath obtained a better result than the others. Therefore, it can be concluded that the Cinnamomum zeylanicum aqueous extract presented inhibitory potential. Considering this, we suggest that more studies with this thematic should be carried out, seeking to discover new alternatives for wood preservatives that are less damaging to the environment and to mankind. [ABSTRACT FROM AUTHOR]

The natural durability of wood refers to its temporal resistance to biological organisms of deterioration, and its determination your knowledge associated of mechanical resistance allows classification of use of the material. Considering the variation among species, the aimed of this study was to evaluate the natural durability and mechanical resistance of three eucalyptus species: Eucalyptus cloeziana F. Muell, E. grandis Hill ex Maiden e E. urophylla S.T. Blake (Myrtaceae). The samples were taken to the climatic chamber before being submitted to the rotting fields until they reached a constant mass at a moisture content of 12%, so the apparent density was calculated and samples sent for exposition area. For this, 48 samples were installed in the rotting field, being 24 in the open field and 24 into a forest, and distributed by completely randomized design. At the end of 13 months, the percentage of mass loss and dynamic bending were evaluated. The E. cloeziana, exposed in the forest and E. grandis, in the field, presented the best results, both classified as resistant, the largest biomass loss was submitted to E. urophylla, in the field area. The results indicate that residual mechanical strength is more related to the density of the species than to the resistance class of the species. [ABSTRACT FROM AUTHOR]

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

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

The aim of this study was verify the drying rate and the wood quality from Hovenia dulcis, subjected to three drying processes (45, 60 and 75 °C). This way, 45 boards with the followings dimensions were used: 25 x 100 x 500 mm. These boards were dried until reach a moisture of 10%. The defects were quantified using a caliper, measuring the maximum deformation in the middle or in an extremity of the piece, depending on the type of defect. The results showed that the drying rate until 30% was greater than the others were and increased with higher temperatures, except for the 45 °C process, not only in the hygroscopic stage but also from green condition to 10% of moisture. Although some warps have happened, the values were lower than those ones admitted by classification rules of sawn wood. Based on this information, it is recommended the usage of conventional process for wood drying of Hovenia dulcis. [ABSTRACT FROM AUTHOR]

The knowledge about the technological properties of the wood enables the achievement of tools that assist in the adequate use of this material. Therefore, the aim of this study was accomplish the technological characterization of Eucalyptus benthamii wood for potential uses. For this, it was used six trees of the forestry plantation implanted in the Guatambu city, Santa Catarina State, Brazil. For the physical characterization of the wood, discs were obtained at three different positions of the trunk of each tree, determining the basic density and retractibility. The test pieces to the mechanical tests of parallel compression to the fibers, dynamic bending, static bending and Janka hardness were obtained from discs removed of the logs. The average basic density was 0.549 g cm-3, while the retractibility parameters were similar to those of genus eucalyptus, with an average anisotropy coefficient of 1.9, indicating that it is a specie unstable dimensionally. The results obtained from the mechanical tests show that the Eucalyptus benthamii wood has less resistant to mechanical stress, limiting its use for this purpose. Therefore, the application of this species for purposes applying mechanical stress is limited, making it necessary carrying out studies about the other properties of this wood. [ABSTRACT FROM AUTHOR]

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