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Arthur Germano Fettneto - One of the best experts on this subject based on the ideXlab platform.

  • resin tapping transcriptome in adult slash pine Pinus elliottii var elliottii
    Industrial Crops and Products, 2019
    Co-Authors: Camila Fernanda De Oliveira Junkes, Artur Teixeira De Araujo, Julio Cesar De Lima, Fernanda De Costa, Thanise Nogueira Fuller, Marcia Rodrigues De Almeida, Franciele Antonia Neis, Kelly Cristine Da Silva Rodriguescorrea, Janette Palma Fett, Arthur Germano Fettneto
    Abstract:

    Abstract To better understand the bases of resin production, a major source of terpenes for industry, the transcriptome of adult Pinus elliottii var. elliottii (slash pine) trees under field commercial resinosis was obtained. Samples were collected from cambium after 5 and 15 days of treatment application, which included tapping followed by application of commercial resin stimulant paste or control wounding without paste. Overall mean number of reads of all 16 libraries (2 treatments x 2 times x 4 replicated trees) was 34,582,048. Of these, 89% were mapped against the reference sequence, with a mismatch of 0.58%. Using the Blast2Go, 570 candidate genes were detected based on sequence annotation. By comparing the expression profile between paste and control, 310 differentially expressed genes (DEGs) were identified at 5 days, and 190 at 15 days with a significant fold change of log2 > 1.2. Regarding changes in time comparisons within each treatment, 210 and 105 DEGs were identified within control and paste treatment, respectively. Genes with different expression patterns in the times and treatments examined included ethylene responsive transcription factors, geranylgeranyl diphosphate synthase, diterpene synthase, cytochrome P450 and ABC transporters, all of which may play important roles in resin production. RT-qPCR analysis correlated well with the data obtained by RNAseq. Resin composition changed over time. This is the first transcriptomic investigation of resinosis of the main species used in the bioresin industry and of molecular analyses of resinosis under field operations, with implications for stand management, stimulant paste development, genotype selection and breeding for high resinosis.

  • resinosis of young slash pine Pinus elliottii engelm as a tool for resin stimulant paste development and high yield individual selection
    Industrial Crops and Products, 2019
    Co-Authors: Camila Fernanda De Oliveira Junkes, Janette Palma Fett, Joao Vitor Vigne Duz, Magnus Riffel Kerber, Julia Wieczorek, Juliana Lunelli Galvan, Arthur Germano Fettneto
    Abstract:

    Abstract Pine resin, a natural source of industrially relevant terpenes, is a major non-wood forestry commodity. Resin is obtained by wounding the bark of adult trees and applying stimulant pastes with different adjuvants on the wound. Identifying new adjuvants and high resin producing trees in adult forests often requires long time and intense labor. Microtapping, i.e. use of young plants of Pinus elliottii var. elliottii cultivated in greenhouse to extract resin, was evaluated as an alternative to carry out these activities. Compounds with known effect in adult plants (ethrel, benzoic acid and potassium sulfate) and molecules involved in the transduction of defense signals (methyl jasmonate, salicylic acid, linolenic acid and isoleucine) were evaluated in young plants. One, two and three-year-old plants consistently increased resinosis when treated with potent adjuvants, mainly methyl jasmonate. The more lignified basal stems produced more resin than apical ones in the 1-year-old plants. Resin yield increased after the second year. All plants were responsive to successive stimuli, just as adult plants. High resin-yield individuals were identified by microtapping, and this phenotype was further supported by terpene-related gene expression studies associated with resinosis. Therefore, microtapping can be used for early, rapid, and simple identification of adjuvants with high resin induction capacity and of putative elite individuals for field evaluation, breeding, and clonal propagation.

  • dual allelopathic effects of subtropical slash pine Pinus elliottii engelm needles leads for using a large biomass reservoir
    Industrial Crops and Products, 2017
    Co-Authors: Kelly Cristine Da Silva Rodriguescorrea, Fernanda De Costa, Gelson Halmenschlager, Joseli Schwambach, Emili Mezzomotrevizan, Arthur Germano Fettneto
    Abstract:

    Pinus elliottii Engelm. (slash pine) is distributed along the maritime coast of Southern Brazil, where it shows invasive pattern and typical allelopathic features. Large quantities of needle litter are produced by pine trees, a biomass that is little explored in areas where this species is alien. Little is known about the dynamics of needle and litter phytochemical interactions, particularly in subtropical environments. To elucidate the full range of needle and litter allelopathic potential, the effects of litter (superficial and deep) and seasonally harvested fresh slash pine needles stored for different times were evaluated against lettuce, tomato and cucumber seeds and seedlings. Increasing concentrations (0%, 1%, 2%, 4%, and 8% w/v) of hot and cold aqueous extracts of needles and litter affected in different ways target plant development. Growth and germination inhibition were directly related to the highest extract concentrations (regardless of the season and mainly in hot water extracts) of needles. On the other hand, stimulatory effects of litter extracts on lettuce growth were observed. Growth and germination of cucumber and tomato were not affected by pine litter as substrate when compared to rice husk. The presumable high polarity and thermal stability of slash pine leaf biomass allelochemicals and their transient toxic effect or growth promoting impact suggest potential applications of this largely available biomass both as a biological herbicide and growth substrate in plant propagation.

  • oleoresin yield of Pinus elliottii in a subtropical climate seasonal variation and effect of auxin and salicylic acid based stimulant paste
    Industrial Crops and Products, 2009
    Co-Authors: Kelly C S Rodrigues, Arthur Germano Fettneto
    Abstract:

    The extraction of induced oleoresin from Pinus elliottii through bark streaking supplies products to the food, pharmaceutical and chemical industries. Resin flow is a typical defense response in conifers and is controled by various environmental factors. Although many studies have focused on oleoresin production in temperate forests, particularly in response to bark beetle attacks, relatively little is known about the physiological regulation of sustainable resin exudation in subtropical planted forests, in which commercial exploitation of this product is favored by the absence of significant pest insect populations. Therefore, the annual oleoresin yield of approximately 2660, 28-year-old trees from different sites was monitored for two consecutive years in southern Brazil. Plain wounding and wounding followed by application of a commercial resin stimulant paste containing the ethylene precursor 2-chloroethylphosphonic acid (CEPA) were used as reference treatments. Different concentrations of auxin, paraquat, yeast extract, and salicylic acid (isolated or in combination with CEPA) were also tested. Higher resin yields were associated with spring and summer, whereas winter had lower but significant yields. Auxin and salicylic acid stimulated the production of oleoresin relative to commercial paste in at least one concentration. Replacement of CEPA with auxin or salicylic acid yielded equivalent oleoresin production, indicating a comparable or complementary effect of these molecules in the process, as well as having implications for new stimulant paste formulations.

Ricardo Marius Della Lucia - One of the best experts on this subject based on the ideXlab platform.

  • propriedades de chapas de aglomerado confeccionadas com misturas de particulas de eucalyptus spp e Pinus elliottii
    Revista Arvore, 2007
    Co-Authors: Carla Priscilla Tavora Cabral, Benedito Rocha Vital, Ricardo Marius Della Lucia, Alexandre Santos Pimenta
    Abstract:

    This work aimed to evaluate properties of particleboards manufactured with particles derived from planner shavings and flakes of Eucalyptus grandis, E. urophylla and E. cloeziana. Pinus elliottii particles were mixed with eucalyptus particles when necessary and in an amount enough to keep boards densities at 0.70 gr/cm3. Eucalyptus wood was obtained from the municipalities of Ponte Alta (Vale do Rio Doce) and Tres Marias (Cerrado Region), both in Minas Gerais state, Brazil. Eucalyptus grandis, E. urophylla and E. cloeziana densities collected in Ponte Alta were 0.55; 0.61 and 0.70 g/cm3 whereas those collected from Tres Marias were 0.58; 0.58 and 0.69 g/cm3, respectively. The density of Pinus elliottii cultivated in the region of Vicosa was 0.45 g/cm3. Particles were produced by processing flakes (0.48 x 20 x 90 mm) and planner shavings in hammer mill. Mean slenderness ratios were 19.87 and 4.66 for particles produced from flakes and shavings, respectively. Urea-formaldehyde adhesive was applied in the proportion of 8% of particle dry mass. Boards manufactured with higher amount of eucalyptus particles absorbed more water and had higher swelling and linear expansion. Highest hardness and parallel compression were observed on boards manufactured with particles from shavings, whereas highest internal bond, modulus of rupture and elasticity values were found for boards fabricated with particles from flakes. Boards made with particles from wood derived from Tres Marias had higher means for parallel compression, internal bond and modulus of rupture.

  • quality of wood joints glued with wood veneers from three trunk regions of eucalyptus grandis eucalyptus saligna and Pinus elliottii
    Revista Arvore, 2006
    Co-Authors: Benedito Rocha Vital, Antonio Da Silva Maciel, Ricardo Marius Della Lucia
    Abstract:

    Este experimento teve como objetivo avaliar a resistencia de juntas coladas formadas pelas combinacoes de lâminas provenientes de tres posicoes no tronco da madeira de Eucalyptus grandis, Eucalyptus saligna e Pinus elliottii. Foram empregados adesivos a base de poliacetato de vinila de media e alta viscosidade e resorcinol-formaldeido nas gramaturas de 150 g/m2, em face simples para o poliacetato de vinila de media e alta viscosidades e 300 g/m2, em face dupla, para o adesivo resorcinolico. O teor medio de umidade das lâminas, no momento da colagem, foi igual a 14%. Os valores medios mais elevados de resistencia ao cisalhamento foram obtidos nas juntas produzidas com madeira de Eucalyptus saligna, coladas com adesivos de poliacetato de media viscosidade e resorcinol-formaldeido. A maior porcentagem de falha profunda na madeira foi obtida em juntas de madeira de Pinus elliottii, unidas com adesivo de poliacetato de alta viscosidade, seguidas das juntas de Eucalyptus grandis e coladas com adesivo de poliacetato de media viscosidade. As combinacoes de lâminas oriundas das seguintes posicoes no tronco: medula e casca, intermediaria e casca e casca e casca resultaram em linhas de cola com maiores resistencias ao cisalhamento.

  • qualidade de juntas coladas com lminas de madeira oriundas de trs regi es do tronco de eucalyptus grandis eucalyptus saligna e Pinus elliottii 1
    Revista Arvore, 2006
    Co-Authors: Benedito Rocha Vital, Antonio Da Silva Maciel, Ricardo Marius Della Lucia
    Abstract:

    Este experimento teve como objetivo avaliar a resistencia de juntas coladas formadas pelas combinacoes de lâminas provenientes de tres posicoes no tronco da madeira de Eucalyptus grandis, Eucalyptus saligna e Pinus elliottii. Foram empregados adesivos a base de poliacetato de vinila de media e alta viscosidade e resorcinol-formaldeido nas gramaturas de 150 g/m2, em face simples para o poliacetato de vinila de media e alta viscosidades e 300 g/m2, em face dupla, para o adesivo resorcinolico. O teor medio de umidade das lâminas, no momento da colagem, foi igual a 14%. Os valores medios mais elevados de resistencia ao cisalhamento foram obtidos nas juntas produzidas com madeira de Eucalyptus saligna, coladas com adesivos de poliacetato de media viscosidade e resorcinol-formaldeido. A maior porcentagem de falha profunda na madeira foi obtida em juntas de madeira de Pinus elliottii, unidas com adesivo de poliacetato de alta viscosidade, seguidas das juntas de Eucalyptus grandis e coladas com adesivo de poliacetato de media viscosidade. As combinacoes de lâminas oriundas das seguintes posicoes no tronco: medula e casca, intermediaria e casca e casca e casca resultaram em linhas de cola com maiores resistencias ao cisalhamento.

  • paineis de particulas aglomeradas de madeira de Pinus elliottii engelm poliestireno ps e polietileno tereftalato pet
    Revista Arvore, 2004
    Co-Authors: Antonio Da Silva Maciel, Benedito Rocha Vital, Ricardo Marius Della Lucia, Alexandre Santos Pimenta
    Abstract:

    This work aimed determine the properties of wood particleboards containing particles of polystyrene (PS) and polyethylene therephthalate (PET). Three amounts of polystyrene (0, 25 and 50%), two amounts of PET/PS (5/20 and 10/40%), three amounts (0, 4 and 6%) of urea-formaldehyde or phenol-formaldehyde adhesive and three amounts of polystyrene in toluene solution (0, 4 and 6%), combined with 50, 75 or 100% of particles of Pinus elliottii wood were used. Layer boards measuring approximately 400 x 400 x 10 mm with density approximately equal to 0.60 g/cm3 were produced. Internal bond, rupture and elasticity modulus, screw withdrawal, water absorption and thickness swelling after 24 hours of immersion were determined. The mechanical properties of all the boards were superior to the established by ANSI/A 208.1-1993 standard. All wood/plastic particleboards absorbed more water than those observed in commercial boards. However, the observed thickness swelling was quite similar to the values of commercial wood particleboards. Boards in which the solution of polystyrene was applied presented, in general, the best values for all the properties.

  • avaliacao de algumas propriedades da madeira de eucalyptus grandis eucalyptus saligna e Pinus elliottii
    Revista Arvore, 2003
    Co-Authors: Pedro Nicolau Serpa, Benedito Rocha Vital, Ricardo Marius Della Lucia, Alexandre Santos Pimenta
    Abstract:

    This work aimed to determine sawn wood yield, as well as density, volumetric shrinkage, static bending and compression parallel to grain strength, glue line quality and machining for Eucalyptus grandis, Eucalyptus saligna and Pinus elliottii wood. Three trees of each species, with approximate ages of 50, 40 and 40 years, respectively, were cut into logs on the base, middle and top. Property variations were analyzed in the pith-bark and longitudinal directions. The results showed that all the physical and mechanical properties varied inside the tree in the radial and longitudinal directions. Basic density, bending and compression strength increased in the pith-bark direction, while volumetric shrinkage decreased. Therefore, for obtaining denser, more stable wood with larger bending and compression strength it is necessary to harvest older trees. Considering the variations in the longitudinal direction, it was observed that logs from the medium portion of the tree presented smaller values than those from the base and from the top, in all the analyzed properties. Glue line strength and wood failure presented little differences in relation to adherence among juvenile wood and mature wood in all the positions. In the and mortise-and-tenon test, all the species showed satisfactory results, without occurrence of defects.

Alexandre Santos Pimenta - One of the best experts on this subject based on the ideXlab platform.

  • propriedades de chapas de aglomerado confeccionadas com misturas de particulas de eucalyptus spp e Pinus elliottii
    Revista Arvore, 2007
    Co-Authors: Carla Priscilla Tavora Cabral, Benedito Rocha Vital, Ricardo Marius Della Lucia, Alexandre Santos Pimenta
    Abstract:

    This work aimed to evaluate properties of particleboards manufactured with particles derived from planner shavings and flakes of Eucalyptus grandis, E. urophylla and E. cloeziana. Pinus elliottii particles were mixed with eucalyptus particles when necessary and in an amount enough to keep boards densities at 0.70 gr/cm3. Eucalyptus wood was obtained from the municipalities of Ponte Alta (Vale do Rio Doce) and Tres Marias (Cerrado Region), both in Minas Gerais state, Brazil. Eucalyptus grandis, E. urophylla and E. cloeziana densities collected in Ponte Alta were 0.55; 0.61 and 0.70 g/cm3 whereas those collected from Tres Marias were 0.58; 0.58 and 0.69 g/cm3, respectively. The density of Pinus elliottii cultivated in the region of Vicosa was 0.45 g/cm3. Particles were produced by processing flakes (0.48 x 20 x 90 mm) and planner shavings in hammer mill. Mean slenderness ratios were 19.87 and 4.66 for particles produced from flakes and shavings, respectively. Urea-formaldehyde adhesive was applied in the proportion of 8% of particle dry mass. Boards manufactured with higher amount of eucalyptus particles absorbed more water and had higher swelling and linear expansion. Highest hardness and parallel compression were observed on boards manufactured with particles from shavings, whereas highest internal bond, modulus of rupture and elasticity values were found for boards fabricated with particles from flakes. Boards made with particles from wood derived from Tres Marias had higher means for parallel compression, internal bond and modulus of rupture.

  • paineis de particulas aglomeradas de madeira de Pinus elliottii engelm poliestireno ps e polietileno tereftalato pet
    Revista Arvore, 2004
    Co-Authors: Antonio Da Silva Maciel, Benedito Rocha Vital, Ricardo Marius Della Lucia, Alexandre Santos Pimenta
    Abstract:

    This work aimed determine the properties of wood particleboards containing particles of polystyrene (PS) and polyethylene therephthalate (PET). Three amounts of polystyrene (0, 25 and 50%), two amounts of PET/PS (5/20 and 10/40%), three amounts (0, 4 and 6%) of urea-formaldehyde or phenol-formaldehyde adhesive and three amounts of polystyrene in toluene solution (0, 4 and 6%), combined with 50, 75 or 100% of particles of Pinus elliottii wood were used. Layer boards measuring approximately 400 x 400 x 10 mm with density approximately equal to 0.60 g/cm3 were produced. Internal bond, rupture and elasticity modulus, screw withdrawal, water absorption and thickness swelling after 24 hours of immersion were determined. The mechanical properties of all the boards were superior to the established by ANSI/A 208.1-1993 standard. All wood/plastic particleboards absorbed more water than those observed in commercial boards. However, the observed thickness swelling was quite similar to the values of commercial wood particleboards. Boards in which the solution of polystyrene was applied presented, in general, the best values for all the properties.

  • avaliacao de algumas propriedades da madeira de eucalyptus grandis eucalyptus saligna e Pinus elliottii
    Revista Arvore, 2003
    Co-Authors: Pedro Nicolau Serpa, Benedito Rocha Vital, Ricardo Marius Della Lucia, Alexandre Santos Pimenta
    Abstract:

    This work aimed to determine sawn wood yield, as well as density, volumetric shrinkage, static bending and compression parallel to grain strength, glue line quality and machining for Eucalyptus grandis, Eucalyptus saligna and Pinus elliottii wood. Three trees of each species, with approximate ages of 50, 40 and 40 years, respectively, were cut into logs on the base, middle and top. Property variations were analyzed in the pith-bark and longitudinal directions. The results showed that all the physical and mechanical properties varied inside the tree in the radial and longitudinal directions. Basic density, bending and compression strength increased in the pith-bark direction, while volumetric shrinkage decreased. Therefore, for obtaining denser, more stable wood with larger bending and compression strength it is necessary to harvest older trees. Considering the variations in the longitudinal direction, it was observed that logs from the medium portion of the tree presented smaller values than those from the base and from the top, in all the analyzed properties. Glue line strength and wood failure presented little differences in relation to adherence among juvenile wood and mature wood in all the positions. In the and mortise-and-tenon test, all the species showed satisfactory results, without occurrence of defects.

  • avaliacao de algumas propriedades da madeira de eucalyptus grandis eucalyptus saligna e Pinus elliottii
    Revista Arvore, 2003
    Co-Authors: Pedro Nicolau Serpa, Benedito Rocha Vital, Ricardo Marius Della Lucia, Alexandre Santos Pimenta
    Abstract:

    O objetivo deste trabalho foi determinar o rendimento em madeira serrada, bem como a massa especifica, contracao volumetrica, resistencia a flexao estatica, resistencia a compressao paralela, qualidade da linha de cola e trabalhabilidade das madeiras de Eucalyptus grandis, Eucalyptus saligna e Pinus elliottii. Foram colhidas tres arvores de cada uma destas especies, com idades aproximadas de 50, 40 e 40 anos, respectivamente. De cada arvore foram retiradas tres toras, sendo uma na base, uma no meio e uma no topo do fuste. Foram analisadas as variacoes em algumas propriedades, no sentido medula-casca e no sentido longitudinal. Os resultados mostraram que todas as propriedades fisicas e mecânicas variaram dentro da arvore nos sentidos radial e longitudinal. A densidade basica e as resistencias a flexao e a compressao aumentaram na direcao medula-casca, enquanto a contracao volumetrica diminuiu. Portanto, para obtencao de madeiras mais densas, mais estaveis e com maior resistencia a flexao e a compressao, e necessaria a colheita de arvores mais velhas. Observou-se ainda que as toras da porcao media do fuste, de modo geral, apresentaram menores valores para todas as propriedades determinadas do que as da base e do topo. A resistencia da linha de cola e a porcentagem de falha na madeira para madeira juvenil e adulta apresentaram pouca diferenca em todas as posicoes no fuste. No ensaio de confeccao de espiga e furacao para espiga, todas as especies apresentaram resultados satisfatorios, sem ocorrencia de defeitos.

Benedito Rocha Vital - One of the best experts on this subject based on the ideXlab platform.

  • propriedades de chapas de aglomerado confeccionadas com misturas de particulas de eucalyptus spp e Pinus elliottii
    Revista Arvore, 2007
    Co-Authors: Carla Priscilla Tavora Cabral, Benedito Rocha Vital, Ricardo Marius Della Lucia, Alexandre Santos Pimenta
    Abstract:

    This work aimed to evaluate properties of particleboards manufactured with particles derived from planner shavings and flakes of Eucalyptus grandis, E. urophylla and E. cloeziana. Pinus elliottii particles were mixed with eucalyptus particles when necessary and in an amount enough to keep boards densities at 0.70 gr/cm3. Eucalyptus wood was obtained from the municipalities of Ponte Alta (Vale do Rio Doce) and Tres Marias (Cerrado Region), both in Minas Gerais state, Brazil. Eucalyptus grandis, E. urophylla and E. cloeziana densities collected in Ponte Alta were 0.55; 0.61 and 0.70 g/cm3 whereas those collected from Tres Marias were 0.58; 0.58 and 0.69 g/cm3, respectively. The density of Pinus elliottii cultivated in the region of Vicosa was 0.45 g/cm3. Particles were produced by processing flakes (0.48 x 20 x 90 mm) and planner shavings in hammer mill. Mean slenderness ratios were 19.87 and 4.66 for particles produced from flakes and shavings, respectively. Urea-formaldehyde adhesive was applied in the proportion of 8% of particle dry mass. Boards manufactured with higher amount of eucalyptus particles absorbed more water and had higher swelling and linear expansion. Highest hardness and parallel compression were observed on boards manufactured with particles from shavings, whereas highest internal bond, modulus of rupture and elasticity values were found for boards fabricated with particles from flakes. Boards made with particles from wood derived from Tres Marias had higher means for parallel compression, internal bond and modulus of rupture.

  • quality of wood joints glued with wood veneers from three trunk regions of eucalyptus grandis eucalyptus saligna and Pinus elliottii
    Revista Arvore, 2006
    Co-Authors: Benedito Rocha Vital, Antonio Da Silva Maciel, Ricardo Marius Della Lucia
    Abstract:

    Este experimento teve como objetivo avaliar a resistencia de juntas coladas formadas pelas combinacoes de lâminas provenientes de tres posicoes no tronco da madeira de Eucalyptus grandis, Eucalyptus saligna e Pinus elliottii. Foram empregados adesivos a base de poliacetato de vinila de media e alta viscosidade e resorcinol-formaldeido nas gramaturas de 150 g/m2, em face simples para o poliacetato de vinila de media e alta viscosidades e 300 g/m2, em face dupla, para o adesivo resorcinolico. O teor medio de umidade das lâminas, no momento da colagem, foi igual a 14%. Os valores medios mais elevados de resistencia ao cisalhamento foram obtidos nas juntas produzidas com madeira de Eucalyptus saligna, coladas com adesivos de poliacetato de media viscosidade e resorcinol-formaldeido. A maior porcentagem de falha profunda na madeira foi obtida em juntas de madeira de Pinus elliottii, unidas com adesivo de poliacetato de alta viscosidade, seguidas das juntas de Eucalyptus grandis e coladas com adesivo de poliacetato de media viscosidade. As combinacoes de lâminas oriundas das seguintes posicoes no tronco: medula e casca, intermediaria e casca e casca e casca resultaram em linhas de cola com maiores resistencias ao cisalhamento.

  • qualidade de juntas coladas com lminas de madeira oriundas de trs regi es do tronco de eucalyptus grandis eucalyptus saligna e Pinus elliottii 1
    Revista Arvore, 2006
    Co-Authors: Benedito Rocha Vital, Antonio Da Silva Maciel, Ricardo Marius Della Lucia
    Abstract:

    Este experimento teve como objetivo avaliar a resistencia de juntas coladas formadas pelas combinacoes de lâminas provenientes de tres posicoes no tronco da madeira de Eucalyptus grandis, Eucalyptus saligna e Pinus elliottii. Foram empregados adesivos a base de poliacetato de vinila de media e alta viscosidade e resorcinol-formaldeido nas gramaturas de 150 g/m2, em face simples para o poliacetato de vinila de media e alta viscosidades e 300 g/m2, em face dupla, para o adesivo resorcinolico. O teor medio de umidade das lâminas, no momento da colagem, foi igual a 14%. Os valores medios mais elevados de resistencia ao cisalhamento foram obtidos nas juntas produzidas com madeira de Eucalyptus saligna, coladas com adesivos de poliacetato de media viscosidade e resorcinol-formaldeido. A maior porcentagem de falha profunda na madeira foi obtida em juntas de madeira de Pinus elliottii, unidas com adesivo de poliacetato de alta viscosidade, seguidas das juntas de Eucalyptus grandis e coladas com adesivo de poliacetato de media viscosidade. As combinacoes de lâminas oriundas das seguintes posicoes no tronco: medula e casca, intermediaria e casca e casca e casca resultaram em linhas de cola com maiores resistencias ao cisalhamento.

  • paineis de particulas aglomeradas de madeira de Pinus elliottii engelm poliestireno ps e polietileno tereftalato pet
    Revista Arvore, 2004
    Co-Authors: Antonio Da Silva Maciel, Benedito Rocha Vital, Ricardo Marius Della Lucia, Alexandre Santos Pimenta
    Abstract:

    This work aimed determine the properties of wood particleboards containing particles of polystyrene (PS) and polyethylene therephthalate (PET). Three amounts of polystyrene (0, 25 and 50%), two amounts of PET/PS (5/20 and 10/40%), three amounts (0, 4 and 6%) of urea-formaldehyde or phenol-formaldehyde adhesive and three amounts of polystyrene in toluene solution (0, 4 and 6%), combined with 50, 75 or 100% of particles of Pinus elliottii wood were used. Layer boards measuring approximately 400 x 400 x 10 mm with density approximately equal to 0.60 g/cm3 were produced. Internal bond, rupture and elasticity modulus, screw withdrawal, water absorption and thickness swelling after 24 hours of immersion were determined. The mechanical properties of all the boards were superior to the established by ANSI/A 208.1-1993 standard. All wood/plastic particleboards absorbed more water than those observed in commercial boards. However, the observed thickness swelling was quite similar to the values of commercial wood particleboards. Boards in which the solution of polystyrene was applied presented, in general, the best values for all the properties.

  • avaliacao de algumas propriedades da madeira de eucalyptus grandis eucalyptus saligna e Pinus elliottii
    Revista Arvore, 2003
    Co-Authors: Pedro Nicolau Serpa, Benedito Rocha Vital, Ricardo Marius Della Lucia, Alexandre Santos Pimenta
    Abstract:

    This work aimed to determine sawn wood yield, as well as density, volumetric shrinkage, static bending and compression parallel to grain strength, glue line quality and machining for Eucalyptus grandis, Eucalyptus saligna and Pinus elliottii wood. Three trees of each species, with approximate ages of 50, 40 and 40 years, respectively, were cut into logs on the base, middle and top. Property variations were analyzed in the pith-bark and longitudinal directions. The results showed that all the physical and mechanical properties varied inside the tree in the radial and longitudinal directions. Basic density, bending and compression strength increased in the pith-bark direction, while volumetric shrinkage decreased. Therefore, for obtaining denser, more stable wood with larger bending and compression strength it is necessary to harvest older trees. Considering the variations in the longitudinal direction, it was observed that logs from the medium portion of the tree presented smaller values than those from the base and from the top, in all the analyzed properties. Glue line strength and wood failure presented little differences in relation to adherence among juvenile wood and mature wood in all the positions. In the and mortise-and-tenon test, all the species showed satisfactory results, without occurrence of defects.

Maria Celeste Dias - One of the best experts on this subject based on the ideXlab platform.

  • somatic embryogenesis of hybrid Pinus elliottii var elliottii p caribaea var hondurensis and ploidy assessment of somatic plants
    Plant Cell Tissue and Organ Culture, 2018
    Co-Authors: Sandra Nunes, Liliana Marum, Nelson Farinha, Vanessa Tolentino Pereira, Tânia Almeida, Diana Sousa, Nelia Mano, Joana Figueiredo, Maria Celeste Dias
    Abstract:

    A protocol is described for somatic embryogenesis (SE) Pinus elliottii × P. caribaea, an interspecific pine hybrid of major economic importance. Different embryogenesis conditions were tested, from time of initiation to plant regeneration. Immature megagametophytes containing zygotic embryos of five open pollinated (OP) mother trees were used for SE initiation. An established rate of 10.2% was achieved for explants inoculated on modified Litvay’s medium (mLV), supplemented with BAP (4.5 µM) and 2,4-D (9 µM). Initiation of SE was influenced by the mother-tree genotype however, modification of culture conditions enabled establishment of embryogenic cell lines (ECLs) from all OP seed families. Fifty-two percent of somatic embryos developed to the cotyledonary stage on mLV, supplemented with 40 µM ABA and 6% w/v sucrose. Cotyledonary stage somatic embryos converted to plants at 45–86%. Four months after acclimatization in a greenhouse, plant survival rates ranged between 78 and 94%. Flow cytometry analysis of ploidy, did not show any variation in ECLs and somatic seedlings.

  • plant regeneration from ploidy stable cryopreserved embryogenic lines of the hybrid Pinus elliottii x p caribaea
    Industrial Crops and Products, 2017
    Co-Authors: Sandra Nunes, Liliana Marum, Nelson Farinha, Vanessa Tolentino Pereira, Tânia Almeida, Maria Celeste Dias, Conceicao Santos
    Abstract:

    Abstract Clonal breeding programs of the highly important interspecific hybrid Pinus elliottii var. elliottii and Pinus caribaea var. hondurensis require the establishment of robust cryopreservation protocols, with no genetic variability. Embryonal masses of this hybrid were successfully cryopreserved by a fast slow-freezing method. The protocol was optimized by testing the effects of dimethyl sulfoxide (DMSO) based cryoprotectant solutions, sugar cryoprotectants (e.g. sucrose or maltose, 0.4 M) and different times of pretreatments and pre-cooling storage. The addition of DMSO in a mixture of polyethylene glycol (PEG) 4000 and sucrose (PSD solution), instead of DMSO alone, was beneficial for recovery of cryopreserved cultures. This parameter, together with the time of pre-cooling storage (before plunging in liquid nitrogen), were the factors that most influenced the survival and regrowth rates of embryonal masses. A pretreatment combination of sucrose (0.4 M) and 5% PSD followed by a pre-cooling storage of 24 h allowed the cryopreservation and regrowth of embryogenic cell lines without major genetic variations (DNA-ploidy) or loss of embryogenic potential. Eight of the nine tested embryogenic cell lines survived to the cryopreservation procedures, however the genotype and treatment conditions clearly influenced the response. Somatic embryos maturation and conversion from recovered embryonal masses (EMs) took place according to our standard somatic embryogenesis protocol for Pinus , using modified Litvai (mLV) medium. This is the first report for this hybrid, and the proposed protocol is fast, robust, providing high rates of recovery and working with several genotypes. This protocol’s suitability for industrial breeding programmes was also confirmed by allowing the regeneration of plants with no apparent variability from cryopreserved embryonal masses.

  • physiological characterization and true to typeness evaluation of in vitro and ex vitro seedlings of Pinus elliottii a contribution to breeding programs
    Plant Physiology and Biochemistry, 2016
    Co-Authors: Sandra Nunes, Liliana Marum, Vanessa Tolentino Pereira, Tânia Almeida, Conceicao Santos, Jose Moutinhopereira, Carlos Correia, Helena Oliveira, Jose Miguel Ferreira P De Oliveira, Maria Celeste Dias
    Abstract:

    Pinus elliottii var. elliottii is a pine species with enormous economic value particularly for timber and resin industries, and is subject of high pressure for genetic improvement and cloning elite genotypes. We have recently developed a robust micropropagation protocol for this species. Plantlets performance needs to be evaluated to validate this protocol for further mass propagation. Micropropagated plantlets and seed-derived plants with similar age and shoot length were compared regarding photosynthesis, carbohydrates and pigments content, water status, DNA content and cell cycle dynamics. Micropropagated plantlets had an overall physiological performance similar to seed-derived plants. In particular, except for the transpiration rate (E), CO2 assimilation rate (A) and total soluble sugars (TSS) content, no major differences between plantlets and seedlings in terms of relative water content (RWC), chlorophyll a fluorescence and pigments content were found. Genetic fidelity analyses support that the micropropagation protocol neither induce DNA content changes nor alterations in cell cycle dynamics.