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Zani WNWM, Sidik NJ, Isa NAM, Awal A, Osman NI, Alias N, Nordin MK. 2024. Influence of media variations and growth regulators on in vitro propagation of Dendrocalamus asper bamboo. Nusantara Bioscience 16: 237-244. This study reports the effects of different types of media and combinations of plant growth regulators on the in vitro propagation of Dendrocalamus asper (Schult.f.) Backer bamboo species, a species known for its economic significance and challenges in traditional cultivation. The experiment was initiated through the cultivation of in vitro nodal segments as explants in various strengths (half-strength and full-strength) of Murashige and Skoog's (MS) and Vacin & Went (VW) media, supplemented with 1.0 mg L-1 6-benzylaminopurine (BAP) hormone. Optimal results were achieved in full-strength MS media with 1.0 mg L-1 BAP, with the highest shoot number (5.6 shoots) and length (2.14±0.18 cm), surpassing outcomes in VW media. Shoot multiplication in full-strength MS media, with varying BAP and indole-3-butyric acid (IBA) hormone combinations (0.5, 1.0, 2.0, and 4.0 mg L-1), was conducted. The combination of 4.0 mg L-1 BAP and 0.5 mg L-1 IBA yielded the highest number of shoots (5.17±3.97), while supplementation with 4.0 mg L-1 IBA alone resulted in the longest shoot with 1.89±1.15 cm. These findings underscore the significance of tailored conditions for optimal in vitro propagation of this species. Further investigations could explore additional factors influencing the propagation process for better refinement of bamboo cultivation techniques. [ABSTRACT FROM AUTHOR]

Phytoremediation technology utilises the ability of plants to remove metal toxicity in the soil. Bamboo is one of the fast-growing woody plants that may potentially facilitate the immediate removal of toxic metals from the soil. This study was conducted to identify the potential of Dendrocalamus asper in phytofiltering metal elements from the mining sites such as the Chini watershed in Pahang. Dendrocalamus asper was grown in a greenhouse with several applications of bamboo biochar (BB) and EDTA in addition to the efficiency test in reducing soil contaminants for 100 days. The present study found Dendrocalamus asper with the addition of BB+EDTA had reduced 37.44% Fe, 43.72% As, 79.27% Pb, 22.67% Cd, and 48.60% Al concentration in the soil. The same treatment also showed a higher plant accumulation of metal concentrations Pb (31-fold) followed by Al (1.3-fold), Cr (1.3-fold), As (1.05-fold), Fe (82%) and Cd (81%) compared to the control. Growing bamboo with the combination of BB+EDTA was found to be useful for Pb phytoextraction and suitable as a phytostabiliser for Al, Fe, As, Cr and Cd. The understanding in the potential of Dendrocalamus asper in reducing soil contaminants may benefit stakeholders in managing and r estoring contaminated sites in the fut ure. [ABSTRACT FROM AUTHOR]

Modification of local bamboo‐based catalytic activated carbon with metallic Ag can produce mesopore and micropore types, with a mesopore content of 86%. One of the best ways to reduce formaldehyde concentrations is through catalytic adsorption. In combination with Ag nanoparticle catalyst, formaldehyde adsorption capacity is improved. Adsorption and oxidation reaction experiments are performed in a fixed bed column (di = 10 mm, length = 90 mm). The increase in formaldehyde adsorption associated with the reaction rate of formaldehyde oxidation by metallic Ag is 51 g/mmol. The oxidation reaction of Ag nanoparticles is a bimolecular reaction based on the Langmuir–Hinshelwood mechanism. Formaldehyde can be reduced by 59% and 41% through the role of adsorption and support of catalytic oxidation, respectively. Additionally, harmless gases such as CO2 and H2O are produced within the column. [ABSTRACT FROM AUTHOR]

Bamboo is considered a sustainable construction material due to its ability to grow quickly and its mechanical properties that are comparable to timber. Contributing to the current effort to establish structural bamboo standards in the National Structural Code of the Philippines (NSCP), this study establishes the characteristic compressive strength of four bamboo species: Bambusa vulgaris (36 samples), Dendrocalamus asper (36 samples), Bambusa blumeana (94 samples), and Guadua angustifolia Kunth (30 samples). The samples were subjected to compressive loading following ISO 22157-1 (2017). The characteristic compressive strength values obtained, according to ISO 12122-1 (2014), were 40.35 MPa for B. vulgaris, 40.21 MPa for D. asper, 46.63 MPa for B. blumeana, and 36.99 MPa for G. angustifolia Kunth. Simple linear analysis, one-way ANOVA, and Welch's t-test were used to analyze the correlation models and establish a comparative analysis of the effects of nodes and geometric and physical properties on the compressive strength of bamboo samples. In comparisons of the characteristic compressive strengths obtained from this study to the strengths of unseasoned structural timber of Philippine woods, all bamboo species showed higher strength values than did other woods, and bamboos thus have great potential as an alternative construction material to timber. [ABSTRACT FROM AUTHOR]

Dendrocalamus asper (giant bamboo) is a clumping type of bamboo belonging to the Poaceae family. Due to its economic and environmental value, demand for this species has increased tremendously. Conventional propagation methods have limitations due to low seed viability and the lack of healthy clumps. Therefore, an in vitro mass propagation protocol was developed to provide healthy plants for large-scale plantations. Seeds were used as the explant and they were surface sterilized and cultured on MS medium free of growth regulators. Nodal segments taken from in vitro germinated seedlings were used for shoot initiation. The best medium for shoot induction (MS medium supplemented with 0.0–2.5 mg/L BAP), best medium for multiple shoot induction (MS medium supplemented with 0.0–5.0 mg/L BAP), effect of shoot cluster size (shoot clusters containing 1–4 shoots) and effect of physical state of the medium (semisolid and liquid media) on multiple shoot induction were determined using shoots per node, mean shoot length and mean number of leaves per shoot after 6 weeks of incubation. Elongated shoots were transferred into a rooting medium and the best medium for root induction (MS medium supplemented with 0.0–5.0 mg/L IBA and IAA) and effect of cluster size (shoot clusters containing 1–4 shoots) on rooting were determined using the number of roots and root length after 6 weeks of incubation. All the cultures were maintained under a 16-hour photoperiod. Well-developed plantlets were transferred to coir pellets and after four weeks transferred into different potting mixtures containing different combinations of sand, compost and coir dust. Unless otherwise mentioned there were at least twenty replicates in all treatments. The highest mean number of shoots per node (16.87±0.52), mean shoot length (4.12±0.27 cm) and mean number of leaves per shoot (4.80±0.33) were observed in the MS medium supplemented with 1.0 mg/L BAP. The MS medium supplemented with 2.0 mg/L BAP was the best for multiple shoot induction, shoot cluster with 3 shoots was the best cluster size and the liquid medium had a better effect on shoot multiplication. The half-strength MS medium supplemented with 2.0 mg/L IBA was the best for in vitro root induction with the highest mean number of roots (7.15±0.77) and a mean root length of 10.79±1.11 cm. Shoot clusters with 3 shoots was the best cluster size for root induction. A sand: compost: coir dust (1:1:1) mixture was the best potting mixture giving 100% survival. These findings provide a reliable micropropagation protocol for D. asper, which holds great promise for meeting the growing demand for bamboo resources and promoting sustainable bamboo cultivation.

Drying round bamboo is important to ensure its dimensional stability, to protect it from biological agents and for making high quality products. Conventional kiln drying of bamboo requires extended drying periods. Microwave drying of bamboo has been studied recently and has been reported to be a very fast method of drying. Dendrocalamus asper (Schult. & Schult.f.) Backer is an important, large-sized bamboo, preferred for structural purposes and handicrafts manufacturing. However, it also shows a propensity to develop defects such as cracks during drying. In this study, eight culms of mature D. asper (about 3–3.5 years old) were felled and cut into two halves: upper half and lower half. Both parts were then cut into 900 mm long sections. Twenty sections each from the upper half were dried in a conventional kiln (CKD) at 50 °C and 70% RH; and another 20 sections from the upper half were subjected to microwave-vacuum drying (MWVD) at bamboo wall temperature 60–70 °C and 150 mbar pressure. Similarly, twenty sections each from the lower half bamboo sections were dried using CKD (50 °C, 70% RH), MWVD (bamboo wall at 60–80 °C, 150 mbar) and combination drying in which bamboo sections were first dried in CKD until the moisture content (MC%) dropped to below 30% (26%) and thereafter, further dried using MWVD. The time taken to dry the sections, MC% drop rate, defects, and energy consumption were analysed. MWVD took 12 h (upper half) to 20 h (bottom half) to dry the bamboo sections, whereas CKD took 12–15 days. Combination drying did not offer any major advantages. A lower number of defects were found in MWVD sections compared sections dried by CKD. On average, 3.78 units of electrical energy were consumed for the removal of 1 kg of water from bamboo during MWVD.

Bamboo is a sustainable and cost-effective alternative to traditional construction materials. Despite the fact that three species are well known for structural applications, namely Dendrocalamus asper, Gigantochloa scortechinii, and Gigantochloa levis, the scientific data for their mechanical characterization is scarcely available and widely dispersed. In addition, a systematic literature review appraising the study advancement of mechanical characterization of bamboo had been unavailable. This paper bridges this gap by conducting a systematic literature review (SLR) of the available literature of mechanical characterization of bamboo pole. A total of 54 relevant articles were retrieved from Scopus and snowballing and then put forward through bibliometric analysis using VOSviewer. The results showed that the distribution of data for physical and mechanical characterization of aforementioned species was scattered due to the different location (origin), age, and initial moisture content recorded during empirical work among the researchers. This review's importance and distinctiveness lie in its synthesis of the existing literature on bamboo mechanical characterization. The findings provide a point of reference for both academia and industry by bridging the scarcity of current bamboo engineering data and outlining future possibilities for bamboo research in the building and construction domain.

Bamboo is a sustainable and cost-effective alternative to traditional construction materials. Despite the fact that three species are well known for structural applications, namely Dendrocalamus asper, Gigantochloa scortechinii, and Gigantochloa levis, the scientific data for their mechanical characterization is scarcely available and widely dispersed. In addition, a systematic literature review appraising the study advancement of mechanical characterization of bamboo had been unavailable. This paper bridges this gap by conducting a systematic literature review (SLR) of the available literature of mechanical characterization of bamboo pole. A total of 54 relevant articles were retrieved from Scopus and snowballing and then put forward through bibliometric analysis using VOSviewer. The results showed that the distribution of data for physical and mechanical characterization of aforementioned species was scattered due to the different location (origin), age, and initial moisture content recorded during empirical work among the researchers. This review's importance and distinctiveness lie in its synthesis of the existing literature on bamboo mechanical characterization. The findings provide a point of reference for both academia and industry by bridging the scarcity of current bamboo engineering data and outlining future possibilities for bamboo research in the building and construction domain. [ABSTRACT FROM AUTHOR]

O objetivo do presente trabalho foi avaliar o tratamento químico, a durabilidade e a lixiviação de bambu tratado e submetido a ensaio em campo de apodrecimento. Para isso, foram coletadas hastes de Dendrocalamus asper com diâmetro entre 10 e 15 cm, totalizando 12 amostras. O tratamento químico consistiu de imersão das amostras em solução de borato de cobre cromatado (CCB), nas concentrações de 1 e 3%, e o tratamento controle (imersão em água). Posteriormente, o material foi submetido ao ensaio em campo de apodrecimento por um período de 5 anos. Ao final do período, o material recebeu avaliação visual quanto à deterioração. Foram coletadas amostras representativas dos tratamentos, assim como do solo, para análises de espectrometria. O tratamento com CCB conferiu preservação às hastes de bambu, não apresentando degradação biológica, enquanto o tratamento controle demonstrou estágio elevado de apodrecimento. Quando comparado com estudos semelhantes utilizando madeira, os resultados obtidos se destacaram, sendo que o material de bambu tratado por imersão com CCB apresentou durabilidade elevada. Nas análises de espectrometria, verificou-se que a parte inferior, em contato com o solo, apresentou maior lixiviação de cobre e cromo do que a parte aérea das hastes.

Bamboo has many potential applications in agroforestry systems. This study evaluated the photosynthetic active solar radiation available (PAR) to intercrops in three bamboo species as a function of estimated soil water content in the Brazilian savanna biome (tropical savanna climate with dry winters and rainy summers). The study was conducted from 2019 to 2021 (three to five years after planting), with clumps spaced at 8 × 5 m. PAR was measured below the bamboo at 0900, 1200, and 1500 h in the central, in-row, and inter-row positions. The estimated soil water balance was used to define the water available in the soil, which was correlated with the fraction of available PAR. The lowest value for the available PAR fraction occurred at the end of the maximum soil water content, being lower than 0.20 for Dendrocalamus asper and Dendrocalamus strictus and 0.80 for Guadua angustifolia. D. asper and D. strictus showed an inverse response rate of 0.50% and 0.75%, respectively, in the change in the available PAR fraction for each percentage change in the estimated mean soil water content 60 days prior to the PAR measurement date. G. angustifolia did not show any significant effect because of the smaller size of the culms and clump. The available PAR was correlated with estimated soil water content and species rate response. This information can be used to plan the cutting of bamboo culms to maximize the amount of PAR based on intercrop demand.

The objective of the present work was to evaluate the chemical treatment, durability and leaching of bamboo treated and submitted to rotting field. Stems of Dendrocalamus asper with a diameter between 10 and 15 cm were collected, totaling 12 samples. The chemical treatment consisted of immersion in chromated copper borate (CCB) solutions at concentration of 1 and 3%, and the control treatment (immersion in water). Subsequently, the material was submitted to the rotting field for a period of 5 years. After this period, the material was visually evaluated for deterioration. Representative samples of the treatments and from the soil were collected for spectrometry analyses. The treatment with CCB conferred preservation to the bamboo stems, not showing biological degradation, while the samples from control treatment showed a high stage of decay. When compared with similar studies using wood, the results obtained stand out, where the bamboo treated by immersion in CCB solutions showed high durability. By spectrometry analyses, it was verified that the lower part, in contact with the soil, presented greater leaching of copper and chromium than the aerial part of the stems. [ABSTRACT FROM AUTHOR]

In crop production, phosphorus (P) is the second most important limiting nutrient. However, due to precipitation reactions with Al3+, Fe3+ in acidic soil, or Ca2+ in alkaline soil, its availability in soil is severely limited. Microbes have recently been proposed as a means of increasing the bioavailability of soil phosphate for plants. The goal of this research was to isolate and identify phosphate solubilizing molds (PSM) from various plant rhizospheres, including gadung (Dioscorea hispida Dennst), maize (Zea mays L.), bamboo (Dendrocalamus asper), pineapple (Ananas comosus L.), and banana (Ananas indica L.). PSM was isolated in vitro and then diluted using the dilution plate technique with Pikovskaya's solid medium. Five colonies were confirmed as PSM, namely Talaromyces aculeatus, Metarhizium anisopliae, Fusarium proliferatum, Mucor hiemalis, and Aspergillus niger, out of fourteen colonies formed from those rhizospheres. In the PVK solid medium, these isolates were capable of solubilizing insoluble P with a solubility range of 2.05 to 3.03. Talaromyces aculeatus (125.6 mg L-1), Metarhizium anisopliae (80.76 mg L-1) and Fusarium proliferatum (41.59 mg L-1) were the best P solubilizers, followed by Mucor hiemalis (9.51 mg L-1), and Aspergillus niger (7.85 mg L-1), respectively. The bioinoculants Talaromyces aculeatus and Metarhizium anisopliae had the most potential. [ABSTRACT FROM AUTHOR]

Physical and mechanical properties were evaluated for bamboo-oriented strand boards (BOSB) prepared with combinations of two contrasting bamboo species and bonded with phenol formaldehyde resin under various compression ratios. The strands from the culms of Gigantochloa pseudoarundinacea and Dendrocalamus asper bamboo were steamtreated at a temperature of 126 °C and a pressure of 0.14 MPa for 1 h and then washed with a 1% NaOH solution. Three-layer dual-species bamboooriented strand boards with a shelling ratio of 25 to 50 to 25 (face to core to back) were manufactured with different compression ratios using an 8% phenol formaldehyde adhesive and 1% paraffin. The slenderness ratio and aspect ratio were evaluated by measuring 100 random strands to determine uniformity. The solidity profiles of the dual-species bamboooriented strand boards (thickness direction) were relatively uniform. The modulus of rupture, modulus of elasticity, and internal bond values of the dual-species bamboo-oriented strand boards increased as the compression ratio increased, but the water absorption and thickness swelling decreased. The dual-species bamboo-oriented strand boards prepared with compression ratios of 1.44 to 1.25 and 1.54 to 1.33 met all the requirements of CSA standard 0437 (2011). The optimum compression ratio for the preparation of dual-species bamboo-oriented strand boards was 1.44 to 1.25. [ABSTRACT FROM AUTHOR]

The supply of timber is becoming scarce in the Philippines. Dendocalamus asper (or giant bamboo) is a candidate for safe, sustainable, and low-cost alternative housing to timber. However, its mechanical properties are yet to be established. In this paper, the compressive strength, shear strength, and tensile strength parallel to fiber of Dendrocalamus asper are determined using ISO 22157 and ASTM D143 tests. For the latter, a slight modification of ASTM D143 was employed. The result yielded an improved tensile strength parallel to fiber. The tensile strength was also tested using a modified version of ASTM D143, wherein the length of the test piece was changed to ensure failure within the gauge length. Two hundred (200) samples of 2m-long Dendrocalamus asper (giant bamboo) poles were prepared and used for testing. Equipment was fabricated to the dimensions of the test sample. The obtained tensile strength parallel to fiber using the ISO 22157 method had an average strength of 312.78 MPa for specimens with attached hardwood tabs and 424.43 MPa for specimens with attached softwood tabs while with the Modified ASTM D143-94 method, the average strength was 269.86 MPa. The shear strength parallel to the fibers had an average strength of 10.64 MPa at the internode and 11.87 MPa at the node. Lastly, the compressive strength parallel to the fibers had an average strength of 63.42 MPa at the internode and 55.55 MPa at the node [ABSTRACT FROM AUTHOR]

Redirecting the actual construction industry, which is one of the major sources of global pollution, is relevant to achieve green innovation efficiency. Researching on the potentials of wood species can lead to propose alternatives that allow reducing/reinventing conventional building materials and systems. This investigation aims to determine, evaluate and analyze the biomechanical/structural properties and performances of lightweight sandwich-like composite biopanels made of bamboo, melina and balsa. A total of 92 samples were experimentally tested under compression, bending, shear, tension, density, moisture content, glue and ply-delamination. The experimental data were validated and compensated through 82 finite element analyses. The acquired results were compared with equivalent sections of conventional materials in terms of strength, rigidity, structural behavior and mechanical efficiency. E.g. the results show the biopanels are up to two and three times more mechanically resistant than solid wall bricks and concrete block walls, respectively; and, up to nine times higher in terms of mechanical efficiency than steel. The results from the biomechanical analyses confirm the practical utilization of the wall biopanels into nonconventional building projects even as structural elements; most important, the implementation of the proposed wall biopanels into actual building systems would significantly reduce fatalities and destroyed dwellings during seismic and windy events due to its remarkable flexibility, strength and ductility. [ABSTRACT FROM AUTHOR]

Copper is the third most utilized metal and is a versatile resource with multiple beneficial uses, but it may also become toxic to aquatic life in excess amount. Thus, there is a need to develop methods to reduce the copper contamination in the environment, particularly in bodies of water. Phytoremediation using Dendrocalamus asper may offer an environment-benign and potentially effective method for copper removal though its effectiveness may take several years to materialize for this technology to become cost-effective. By growing D. asper in synthesized contaminated water and analyzing the change in the copper content of the substrate via atomic absorption spectrophotometry, the removal was found to be optimal at 20 ppm Cu and pH 5. The rate of removal was found to have an order of 2.71 and a kinetic constant of 0.0013 ppm−1.71 day−1. With this, it may be possible to estimate the treatment length of phytoremediation given an initial level of copper contamination and a target concentration.

The study was conducted to compare the wettability of Dendrocalamus asper and Bambusa blumeana and to determine thermal treatment effect on the surface property of bamboo. Mature bamboo poles (3 samples per species) were collected from Barangay Masapang, Victoria, Laguna, Philippines. The culms were divided into three height segments representing the bottom, middle and top portions and prepared for the wettability test on the outside layer (towards the skin) and inner surface. The samples for wettability and physical property determination were collected from the middle internode in each portion. Wettability property was determined by the Cosine-Contact Angle (CCA) measurement. ANOVA showed significant differences between species, layers, treated and untreated bamboo and height. The top portion of D. asper and the middle portion of B. blumeana had the highest measured contact angles, which were found in the outside layer for both bamboos. Thermal treatment changed the color of both bamboos, decreased their density, and significantly improved the wettability property. The results showed that the D. asper contact angle was significantly lower at different height levels and layers than B. blumeana for both untreated and thermally-treated samples. [ABSTRACT FROM AUTHOR]

The edible shoots of Dendrocalamus asper (family Poaceae) is an underutilised food. The present work was conducted to evaluate the nutritional compositions, biological activities, and phytochemical contents of the shoots of D. asper obtained from different regions of Malaysia, Peninsular (DP) and East Malaysia (DS). The nutritional analysis was conducted using the Official Methods of Analysis of the AOAC International. All minerals were quantified using an inductively coupled plasma-mass spectrometer, except for potassium which was measured using a flame atomic absorption spectrometer. Total phenolic content (TPC) was determined using the Folin-Ciocalteu method. Antibacterial and antifungal activities were assayed using a colourimetric broth microdilution method, while antioxidant activity was tested using DPPH radical scavenging activity, ferric-reducing antioxidant power, and cellular antioxidant activity (CAA) assays. Enzyme inhibitory activities were examined using α-amylase and α-glucosidase. Both bamboo shoots (boiled at 100°C for 20 min) were high in moisture (> 93 g/100 g FW), crude protein (> 21 g/100 g DW), and crude fibre contents (> 9 g/100 g DW), but low in fat content (< 4 g/100 g DW). Potassium was the most abundant mineral at 205.67 and 203.83 µg/100 g DW of bamboo shoots of DP and DS, respectively. The extracts (hexane, ethyl acetate, ethanol, and water) of both shoots showed stronger antifungal activity than antibacterial activity against selected human pathogens. All extracts of DP shoots demonstrated higher CAA in HeLa cells and α-amylase inhibitory activity than that of DS shoots. In contrast, the extracts of DS shoots exhibited stronger inhibition on α-glucosidase and contained higher TPC than that of DP shoots. The D. asper shoots obtained from the Peninsular Malaysia and East Malaysia contained different types of secondary metabolites which account for the differences in the biological activities. In conclusion, D. asper shoots have potential as a nutritional and functional food. [ABSTRACT FROM AUTHOR]

Bamboos represent an emerging forest resource of economic significance and provide an avenue for sustainable development of forest resources. The development of the commercial bamboo industry is founded upon efficient molecular and technical approaches for the selection and rapid multiplication of elite germplasm for its subsequent propagation via commercial agro-forestry business enterprises. This review will delve into the micropropagation of Dendrocalamus asper, one of the most widely cultivated commercial varieties of bamboo, and will encompass the selection of germplasm, establishment of explants in vitro and micropropagation techniques. The currently available information pertaining to molecular biology, DNA barcoding and breeding, has been included, and potential areas for future research in the area of genetic engineering and gene regulation have been highlighted. This information will be of relevance to both commercial breeders and molecular biologists who have an interest in establishing bamboo as a crop of the future.

Dense wood batten panels usually break in the glue line when loaded. This study demonstrates that thin veneers obtained from mature culms of Dendrocalamus asper by mechanical grinding are suitable for coating and reinforcing solid processed eucalyptus wood and eucalyptus batten panels. Tensile and bending tests were carried out on Corymbia citriodora timber and edge glued batten panels, with and without bamboo veneer reinforcement. The tensile test results showed that the bamboo veneers glued onto the wood and edge glued batten panels specimens acted as a mechanical reinforcement for both cases, when submitted to tensile forces parallel to the bamboo fibers. In bending tests, the edge glued batten panels specimens were tested transversally to the glue line, direction in which the panel showed the lowest mechanical resistance. The edge glued batten panels specimens without reinforcement with laminated bamboo exhibited a fragile behavior and ruptured abruptly along the glue line. A significant increase in the mechanical strength of the set was observed for the edge glued batten panels coated with laminated bamboo. In addition, the mechanical behavior changed in reinforced specimens, which ruptured slowly and gradually in the bending tests.

Bamboo is an abundant plant in tropical regions, which can be used as a nonconventional structural material; however, there is a high variability in its mechanical properties. This study aimed to evaluate the influence of the moisture content and of the sections (with and without node) on the tensile strength parallel to the culm fibers of three bamboo species (Dendrocalamus asper, Phyllostachys pubescens and Phyllostachys aurea), aiming at their use for structural purposes. For each moisture condition (ambient, saturated in water, oven dried and control), a completely randomized design, following a 3 x 2 factorial scheme, was used. Phyllostachys pubescens exhibited a higher tensile strength parallel to the fibers than the other species. In general, the node affected negatively the tensile strength parallel to the fibers for all analyzed conditions, while the moisture content did not show a significant influence, although the descriptive analysis exhibited its influence on the dimensional variations and water absorption.

Copyright of Investigacion y Amazonia is the property of Investigacion y Amazonia 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.)

Abstract This paper studied two alternative polymeric films based on natural latex and rosin as a waterproofing coating for 3-layer sugarcane-bamboo-based particleboards (3LP). To study the roughness as well as evaluate the coating surfaces on the 3LP, scanning confocal electron microscopy (SCEM) was used. The wettability performance of the coatings was evaluated by the surface energy through the contact angle method. The 3LP coated thermal, physical and mechanical properties were evaluated following ASTM-E1530: 2011 and ABNT NBR 14810 standards, respectively. Physical results indicated latex and rosin coatings significantly decreased water permeability in the 3LP showing swelling in thickness (TS) values of 1.72 and 2.43%, respectively, when compared 3LP without coating (3LP-Control) of 12.90%. The latex and rosin coatings on the 3LP did not influence the thermal properties. Mechanical properties of modulus of rupture (MOR)and modulus of elasticity (MOE) under bending solicitation shown that all 3LP met the ANSI Standard A208.1–1999 requirements. Latex successfully formed a smooth and continuous film which covered the surface pores of the 3LP, whereas rosin did not form a smooth and continuous, forming only a thin film on the 3LP. Highlights • Films based on latex and rosin as a waterproofing coating for 3LP • Physical results indicated that the coatings decreased water permeability. • 3LP coated with latex presented TS values of 1.72% after 24 h in water. • 3LP coated with rosin presented TS values of 2.43% after 24 h in water. • Latex formed a smooth and continuous film covering the surface of the 3LP [ABSTRACT FROM AUTHOR]

Copyright of Agricultural Research in the Tropics / Pesquisa Agropecuária Tropical is the property of Pesquisa Agropecuaria Tropical 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 Agricultural Research in the Tropics / Pesquisa Agropecuária Tropical is the property of Pesquisa Agropecuaria Tropical 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.)

This study investigated adhesion properties, such as buffering capacity and wettability, of bamboo and rubberwood and evaluated the physical and mechanical properties of hybrid particleboard made from bamboo (B) veneer waste and rubberwood (RW) particles. The bamboo had an acidic pH value with a high buffering capacity compared with rubberwood. Hybrid bamboo-rubberwood particleboard displayed better mechanical properties compared to 100% bamboo and rubberwood particleboard. All hybrid particleboard panels passed and fulfilled the minimum standard requirements, except for thickness swelling and water absorption tests. However, for thickness swelling test, only boards consisting of 50B:50RW and 30B:70RW passed and fulfilled the minimum TS requirements of the British Standard EN 317 (1993). Panels made from 100% bamboo veneer waste displayed the highest modulus of rupture (MOR) and modulus of elasticity (MOE) values, 15.30 N/mm2 and 2650.14 N/mm2, respectively. Hybrid particleboard panels exhibited better screw withdrawal compared with panels made of only bamboo or rubberwood particles. It is concluded that bamboo veneer waste enhances the quality of particleboards, especially in terms of mechanical strength. Thus, bamboo veneer waste can decrease the dependence of the particleboard industry on rubberwood.

Bamboo water transport comprises the pathway rhizomes-culms-leaves as well as transfer among culms via connected rhizomes. We assessed bamboo water transport in three big clumpy bamboo species by deuterium tracing. The tracer was injected into the base of established culms, and water samples were collected from leaves of the labeled culms and from neighboring culms. From the base of labeled culms to their leaves, the average tracer arrival time across species was 1.2 days, maximum tracer concentration was reached after 1.8 days, and the tracer residence time was 5.6 days. Sap velocities were high (13.9 m d−1). Daily culm water use rates estimated by the tracer method versus rates measured by a calibrated sap flux method were highly correlated (R2 = 0.94), but the tracer estimates were about 70% higher. Elevated deuterium concentrations in studied neighbor culms point to deuterium transfer among culms, which may explain the difference in culm water use estimates. We found no differences in deuterium concentrations between neighbor-established and neighbor freshly sprouted culms of a given species. In two species, elevated concentrations in both neighbor-established and neighbor freshly sprouted culms were observed over an extended period. An applied mixing model suggests that five neighbor culms received labeled water. In contrast, for the third species, elevated concentrations in neighbor culms were only observed at the earliest sampling date after labeling. This could indicate that there was only short-term transfer and that the tracer was distributed more widely across the rhizome network. In conclusion, our deuterium tracing experiments point to water transfer among culms, but with species-specific differences.

Mechanical characteristics were evaluated of wood-bamboo-based particleboard having the proportions of 100% wood and 0% bamboo, 75% wood and 25% bamboo, and 50% wood and 50% bamboo. This particleboard used Eucalyptus urophylla × grandis wood, Dendrocalamus asper bamboo, and castor oil-based polyurethane resin. Through destructive testing, the values of perpendicular tensile, static bending, modulus of elasticity, and screw pullout strength in the top and face surfaces were analyzed. For 0%, 25%, and 50% bamboo the values were 1.68 MPa, 1.37 MPa, and 1.4 MPa, respectively, for perpendicular tensile; 15.2 MPa, 17.6 MPa, and 18.5 MPa, respectively, for static bending; 2466 MPa, 2694 MPa, and 2922 MPa, respectively, for modulus of elasticity; 1256 MPa, 1922 MPa, and 1362 MPa, respectively, for screw pullout strength in top; and 1392 MPa, 1342 MPa, and 1414 MPa, respectively, for screw pullout strength in face. These results were superior to those presented by ABNT NBR 14810 (2013) and ANSI 208.1 (1999). After performing a Tukey test at 5%, the values for each treatment did not show a significant difference among them. [ABSTRACT FROM AUTHOR]

Supercritical carbon dioxide (SC-CO) as a carrier solvent is becoming an alternative and environmentally sound method in the preservative treatment of wood and wood-based products. The potential of this new method has never been explored for its suitability in manufacturing laminated bamboo products which are widely used as construction materials for either indoor or outdoor purposes. The current study was aimed at examining the effect of SC-CO impregnation on the density and bonding strength of laminated bamboo Dendrocalamus asper. Samples of bamboo strip and their laminated products were prepared for impregnation treatments. Some of the bamboo samples were also proportionally divided into four outer-inner sections for the determination of anatomical structure presumed to have a relationship with the properties of laminated products. SC-CO impregnation was conducted in a vessel at the temperature of 35 °C and the pressure of approximately 8 MPa for 30 min. Results showed that SC-CO impregnation resulted in no adverse effects on the density and bonding strength of laminated bamboo. Various responses of laminated bamboo products to the SC-CO impregnation were noticed to associate with the decreased proportions of vascular bundles and the increased proportions of parenchyma cells from outer to inner parts of the bamboo. These results indicate the feasibility of the SC-CO treatment and the important of considering the anatomical structure of bamboo in producing laminates with high strength and durability properties. [ABSTRACT FROM AUTHOR]