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Li-chun Huang - One of the best experts on this subject based on the ideXlab platform.
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Small RNAs of Sequoia Sempervirens during rejuvenation and phase change.
Plant biology (Stuttgart Germany), 2012Co-Authors: Yu-ting Chen, Hsiu-an Chu, Chin-hui Shen, Li-chun Huang, Kai-wun Yeh, Bau-lian Huang, Ching-i Kuo, Wen-dar Lin, Ing-feng ChangAbstract:In this work, the population of small RNAs (sRNAs) was studied in the gymnosperm Sequoia Sempervirens during phase changes, specifically in the juvenile, adult and rejuvenated plants obtained in vitro. The potential target genes of Sequoia sRNAs were predicted through bioinformatics. Rejuvenation is a pivotal process in woody plants that enables them to regain their growth potential, which results in the recovery of physiologic and molecular characteristics that were lost when the juveniles mature into adult plants. The results from the five repeated graftings of juvenile, adult and rejuvenated plants in vitro showed that sRNAs could be classified into structural RNAs (Group I), small interfering RNAs (Group II), annotated microRNAs (Group III, and unannotated sRNAs (Group IV). The results indicate that only 573 among 15,485,415 sRNAs (Groups III and IV) had significantly different expression patterns associated with rejuvenation and phase change. A total of 215 sRNAs exhibited up-regulated expression patterns in adult shoots, and 358 sRNAs were down-regulated. Expression profiling and prediction of possible target genes of these unique small RNAs indicate possible functions in the control of photosynthetic efficiency and rooting competence abundance during plant rejuvenation. Moreover, the increase in SsmiR156 and decrease in SsmiR172 during plant rejuvenation suggested that these two microRNAs extensively affect phase transition.
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Photosynthetic properties and photosystem stoichiometry of in vitro-grown juvenile, adult, and rejuvenated Sequoia Sempervirens (D. Don) Endl.
Botanical Studies, 2012Co-Authors: Hsiu-an Chu, Ing-feng Chang, Chin-hui Shen, Yu-ting Chen, Hsing-ting Wang, Li-chun Huang, Kai-wun YehAbstract:Photosynthetic properties and photosystem stoichiometry of in vitro-grown juvenile, adult, and rejuvenated Sequoia Sempervirens shoots were characterized. 77K fluorescence analysis indicated that photosystem II/photosystem I ratios were highest for chloroplasts in adult shoots. Photosynthetic oxygen evolution rates (on the same chlorophyll bases) were also slightly higher for chloroplasts in adult shoots. Our results suggested a significant alteration of photosystem stoichiometry in chloroplasts of Sequoia Sempervirens shoots during phase change. In addition, chlorophyll a fluorescence analysis showed that juvenile, adult, and rejuvenated shoots showed virtually identical maximal quantum efficiencies of photosystem II (F(subscript V)/F(subscript M)). Nonphotochemical quenching (NPQ) during actinic light illumination, however, was significantly enhanced for AS76 adult shoots. The differences in photosynthetic properties and photosystem stoichiometry among juvenile, adult, and rejuvenated shoots may reflect adjustments in the photosynthetic apparatus to acclimate to distinct physiological states of Sequoia Sempervirens during phase changes.
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Phase- and age-related differences in protein tyrosine phosphorylation in Sequoia Sempervirens
Biologia Plantarum, 2003Co-Authors: Li-chun Huang, Toshio Murashige, Tsong Teh Kuo, Dinq-ding Huang, Hao Jen HuangAbstract:Apical and basal halves of 3 cm long apical segments of in vitro cultured juvenile, adult and rejuvenated Sequoia Sempervirens shoots were analyzed for total and tyrosine phosphorylated proteins. The latter was detected by a phosphotyrosine specific antibody. Younger tissues, or the apical halves of shoot terminals, showed larger amounts of 36, 44, 46 kDa proteins and lesser amounts of 29 kDa proteins. These are proposed as age-related changes. Phase-related proteins were also evident. Adult tissues contained more of the 34 and 36 kDa proteins than juvenile and rejuvenated shoots. Western blotting with a phosphotyrosine specific antibody revealed more of 25, 39, and 54 kDa protein in the younger tissues. In addition, tyrosine phosphorylated proteins of 25 and 34 kDa were higher in the adult, than in juvenile or rejuvenated tissues. Our findings showed that protein tyrosine phosphorylation, or the signal transduction pathway, is involved in phase- and age-related processes.
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Photosynthetic potentials of in vitro-grown juvenile, adult, and rejuvenated Sequoia Sempervirens (D. Don) Endl. shoots
Botanical Bulletin of Academia Sinica, 2003Co-Authors: Li-chun Huang, Ching-i Kuo, Chiu-hui Wang, Jui-hsi Weng, Yuh-jang ShiehAbstract:In vitro shoot tips of Sequoia Sempervirens (D. Don.) Endl including a juvenile, two adult, and two rejuvenated adult clones were examined for differences in basic physiological characteristics Moisture contents were the same, around 85%, for all tissues regardless of origin Growth rates, determined by fresh weight increase and shoot elongation, were higher for the juvenile and rejuvenated shoots They correlated with higher total nitrogen contents Juvenile and rejuvenated shoots also showed higher rates of photosynthesis and respiration, evidenced by faster O2 evolution and consumption The photosynthetic rates were associated with more chlorophyll, especially chlorophyll a, in the juvenile and the rejuvenated shoots Nevertheless, identical quantum efficiencies of photosystem II indicated the same photosystems were operating and with equal effectiveness in juvenile, adult, and rejuvenated tissues.
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Ethylene evolution by juvenile and adult developmental phases of Sequoia Sempervirens shoots cultured in vitro.
Botanical Bulletin of Academia Sinica, 2000Co-Authors: Li-chun Huang, Ching-i Kuo, Toshio Murashige, Chiu-hui Wang, Tan-chi HuangAbstract:Cultures of juvenile and rejuvenated Sequoia Sempervirens shoots generated more ethylene than those of adult shoots. But the higher phytohormone production was only indirectly related to the developmental phase. The juvenile and rejuvenated shoots also grew more rapidly; thus, when measured on a per gram tissue basis the rates of ethylene evolution were the same for tissues of both developmental phases, and even higher for one of the adults. The investigation did not establish whether the faster growth of juvenile and rejuvenated shoots was caused by the ethylene; on the other hand, there was no evidence of inhibitory effects.
Einar Timdal - One of the best experts on this subject based on the ideXlab platform.
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Xylopsora canopeorum (Umbilicariaceae), a new lichen species from the canopy of Sequoia Sempervirens
MycoKeys, 2018Co-Authors: Mika Bendiksby, Rikke Reese Næsborg, Einar TimdalAbstract:Xylopsora canopeorum Timdal, Reese Naesborg & Bendiksby is described as a new species occupying the crowns of large Sequoia Sempervirens trees in California, USA. The new species is supported by morphology, anatomy, secondary chemistry and DNA sequence data. While similar in external appearance to X. friesii, it is distinguished by forming smaller, partly coralloid squamules, by the occurrence of soralia and, in some specimens, by the presence of thamnolic acid in addition to friesiic acid in the thallus. Molecular phylogenetic results are based on nuclear (ITS and LSU) as well as mitochondrial (SSU) ribosomal DNA sequence alignments. Phylogenetic hypotheses obtained using Bayesian Inference, Maximum Likelihood and Maximum Parsimony all support X. canopeorum as a distinct evolutionary lineage belonging to the X. caradocensis-X. friesii clade.
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Xylopsora canopeorum (Umbilicariaceae), a new lichen species from the canopy of Sequoia Sempervirens
Pensoft Publishers, 2018Co-Authors: Mika Bendiksby, Rikke Reese Næsborg, Einar TimdalAbstract:Xylopsora canopeorum Timdal, Reese Næsborg & Bendiksby is described as a new species occupying the crowns of large Sequoia Sempervirens trees in California, USA. The new species is supported by morphology, anatomy, secondary chemistry and DNA sequence data. While similar in external appearance to X. friesii, it is distinguished by forming smaller, partly coralloid squamules, by the occurrence of soralia and, in some specimens, by the presence of thamnolic acid in addition to friesiic acid in the thallus. Molecular phylogenetic results are based on nuclear (ITS and LSU) as well as mitochondrial (SSU) ribosomal DNA sequence alignments. Phylogenetic hypotheses obtained using Bayesian Inference, Maximum Likelihood and Maximum Parsimony all support X. canopeorum as a distinct evolutionary lineage belonging to the X. caradocensis–X. friesii clade
Silvana Nisgoski - One of the best experts on this subject based on the ideXlab platform.
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Dimensional variation of axial tracheids along the stem of Sequoia Sempervirens Endl (Lamb.)
Scientia Agraria Paranaensis, 2017Co-Authors: Bruna Verediana Müller, Alexsandro Bayestorff Da Cunha, Silvana Nisgoski, Graciela Inés Bolzon De Muñiz, Joanna Rebelo De Oliveira, Veruschka Rocha Medeiros AndreollaAbstract:The present study aimed to evaluate the dimensional variation of axial tracheids along the stem of Sequoia Sempervirens Endl (Lamb.). Three trees with approximately 18 years old were selected, of which six discs were removed from along the height. Of each disk, three samples were taken from the vascular cambium to the medulla. For each sample we proceeded to measure the individual characteristics of tracheids. As a procedure of analyzing the results, we applied the Tukey test at 95% probability. The results indicated that the values for the characteristics of tracheids resemble those reported in the literature for the genus Pinus or species belonging to Gymnosperms, except the cell wall thickness, whose values were high. Regarding the variation of dimensions, only the length of tracheids from the vascular cambium to the medulla, indicated statistically a standard of variation. Evaluated traits, both in the vascular cambium to the medulla sense, as along the height, showed no definitive trend of variation.
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avaliacao colorimetrica de aglomerados produzidos com particulas de madeira de Sequoia Sempervirens e pinus taeda submetidos ao intemperismo natural
Floresta e Ambiente, 2014Co-Authors: Vinicius Gomes De Castro, Setsuo Iwakiri, Rafael Leite Braz, Karine Ramos Da Rosa Bellon, Felipe Gustavo Sanches, Silvana NisgoskiAbstract:The aim of this work was to establish the effect of using different amounts of Sequoia Sempervirens and Pinus taeda wood particles on the colorimetric properties of particleboard and to evaluate the color change after outdoor weathering for six months. The colorimetric properties were measure according to the CIE-L*a*b* 1976 system. The results indicated a direct relation between the proportion of Sequoia Sempervirens wood particles used in the blend and the red pigment values (a*) and an indirect relation with the yellow pigment (b*). Thus the final color of a particleboard can be predicted by controlling the amount of particles from the different species used in particleboard production. However, natural weathering for 4 months is sufficient to decrease a* and b* values and eliminate the color difference between the particleboards.
Mika Bendiksby - One of the best experts on this subject based on the ideXlab platform.
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Xylopsora canopeorum (Umbilicariaceae), a new lichen species from the canopy of Sequoia Sempervirens
MycoKeys, 2018Co-Authors: Mika Bendiksby, Rikke Reese Næsborg, Einar TimdalAbstract:Xylopsora canopeorum Timdal, Reese Naesborg & Bendiksby is described as a new species occupying the crowns of large Sequoia Sempervirens trees in California, USA. The new species is supported by morphology, anatomy, secondary chemistry and DNA sequence data. While similar in external appearance to X. friesii, it is distinguished by forming smaller, partly coralloid squamules, by the occurrence of soralia and, in some specimens, by the presence of thamnolic acid in addition to friesiic acid in the thallus. Molecular phylogenetic results are based on nuclear (ITS and LSU) as well as mitochondrial (SSU) ribosomal DNA sequence alignments. Phylogenetic hypotheses obtained using Bayesian Inference, Maximum Likelihood and Maximum Parsimony all support X. canopeorum as a distinct evolutionary lineage belonging to the X. caradocensis-X. friesii clade.
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Xylopsora canopeorum (Umbilicariaceae), a new lichen species from the canopy of Sequoia Sempervirens
Pensoft Publishers, 2018Co-Authors: Mika Bendiksby, Rikke Reese Næsborg, Einar TimdalAbstract:Xylopsora canopeorum Timdal, Reese Næsborg & Bendiksby is described as a new species occupying the crowns of large Sequoia Sempervirens trees in California, USA. The new species is supported by morphology, anatomy, secondary chemistry and DNA sequence data. While similar in external appearance to X. friesii, it is distinguished by forming smaller, partly coralloid squamules, by the occurrence of soralia and, in some specimens, by the presence of thamnolic acid in addition to friesiic acid in the thallus. Molecular phylogenetic results are based on nuclear (ITS and LSU) as well as mitochondrial (SSU) ribosomal DNA sequence alignments. Phylogenetic hypotheses obtained using Bayesian Inference, Maximum Likelihood and Maximum Parsimony all support X. canopeorum as a distinct evolutionary lineage belonging to the X. caradocensis–X. friesii clade
Vinicius Gomes De Castro - One of the best experts on this subject based on the ideXlab platform.
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Avaliação colorimétrica de aglomerados produzidos com partículas de madeira de Sequoia Sempervirens e Pinus taeda submetidos ao intemperismo natural
Instituto de Florestas da Universidade Federal Rural do Rio de Janeiro, 2014Co-Authors: Vinicius Gomes De Castro, Braz,rafael LeiteAbstract:O objetivo do presente trabalho foi estabelecer o efeito do uso de misturas de diferentes proporções de partículas de Sequoia Sempervirens e Pinus taeda nas propriedades colorimétricas de aglomerados, além de avaliar a alteração natural da cor após exposição ao intemperismo natural por seis meses. As análises colorimétricas foram realizadas através do sistema CIE-L*a*b* 1976. Os resultados indicaram uma relação direta das proporções de partículas de Sequoia Sempervirens com os valores médios do pigmento vermelho (a*) e uma relação indireta com os valores do pigmento amarelo (b*). Desta maneira, a cor do produto final pode ser prevista de acordo com o controle de proporções de partículas de diferentes espécies. Contudo, a exposição do material à luz natural por quatro meses é o suficiente para afetar negativamente os pigmentos a* e b*, e tende a eliminar a diferença de cores entre os painéis
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avaliacao colorimetrica de aglomerados produzidos com particulas de madeira de Sequoia Sempervirens e pinus taeda submetidos ao intemperismo natural
Floresta e Ambiente, 2014Co-Authors: Vinicius Gomes De Castro, Setsuo Iwakiri, Rafael Leite Braz, Karine Ramos Da Rosa Bellon, Felipe Gustavo Sanches, Silvana NisgoskiAbstract:The aim of this work was to establish the effect of using different amounts of Sequoia Sempervirens and Pinus taeda wood particles on the colorimetric properties of particleboard and to evaluate the color change after outdoor weathering for six months. The colorimetric properties were measure according to the CIE-L*a*b* 1976 system. The results indicated a direct relation between the proportion of Sequoia Sempervirens wood particles used in the blend and the red pigment values (a*) and an indirect relation with the yellow pigment (b*). Thus the final color of a particleboard can be predicted by controlling the amount of particles from the different species used in particleboard production. However, natural weathering for 4 months is sufficient to decrease a* and b* values and eliminate the color difference between the particleboards.
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Produção de painéis compensados fenólicos com lâminas de madeira de Sequoia Sempervirens
Floresta e Ambiente, 2013Co-Authors: Setsuo Iwakiri, Alexsandro Bayestoriff Da Cunha, Rosilani Trianoski, Rafael Leite Braz, Vinicius Gomes De Castro, Sandra Kazmierczak, Edson Pinheiro, Heloisa Rancatti, Felipe Luis SanchesAbstract:The aim of this research was to evaluate the quality of plywood made from wood veneers of Sequoia Sempervirens. Plywood with five 2.0 mm thick veneers were produced in laboratory and bonded with phenol-formaldehyde resinusing two different formulations: (A) resin = 100, extender = 5, filler = 5,and water = 5; and (B) resin = 100, extender = 15, filler = 15, and water = 15,with two different amounts of glue spread: 280 g/m2 and 320 g/m2. The panels were pressed with specific pressure of 10 kgf/cm2, temperature of 130 oC, and pressing time of 10 minutes. The properties of the glue line shear strengthand static bending (modulus of elasticity and modulus of rupture - parallel and perpendicular to the grain) were evaluated. In general, the different glue formulations and amounts of glue spread did not significantly affect the properties of the panels,which represent an important aspect from the economic point of view. The shear strengthand percentage of wood failures of the plywood produced withformulation (B) met the minimum requirements of the EN 314-2 (1993) standard to panels for external use. Results indicate that Sequoia Sempervirens veneers can be used to compose the core of plywood for external use.
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producao de paineis compensados com lâminas de madeira de Sequoia Sempervirens e resina ureia formaldeido
FLORESTA, 2012Co-Authors: Setsuo Iwakiri, Rafael Leite Braz, Vinicius Gomes De Castro, Sandra Kazmierczak, Edson Pinheiro, Heloisa Rancatti, Alexsandro Bayestorff Da Cunha, Jose Guilherme Prata, Felipe Luis SanchesAbstract:Resumo Esta pesquisa teve por objetivo avaliar a qualidade dos paineis compensados multilaminados produzidos com lâminas de madeira de Sequoia Sempervirens (D. Don) Endl. Foram produzidos em laboratorio compensados com cinco lâminas de 2,0 mm de espessura, colados com resina ureia-formaldeido (UF), com duas diferentes formulacoes de batida de cola e gramaturas. Os paineis foram prensados com pressao especifica de 10 kgf/cm², temperatura de 110 oC e tempo de prensagem de 10 minutos. Foram avaliadas as propriedades de resistencia da linha de cola aos esforcos de cisalhamento (RLC) e flexao estatica paralelo e perpendicular (MOE e MOR). De uma forma geral, as diferentes formulacoes da batida de cola e gramaturas nao afetaram significativamente os resultados das propriedades dos paineis, o que representa um aspecto importante sob o ponto de vista economico. Os valores medios de RLC e percentagem de falhas na madeira atendem aos requisitos minimos da norma EN 314-2 (1993). Os resultados obtidos nesta pesquisa indicam a possibilidade de uso de lâminas de Sequoia para o miolo de paineis compensados para uso interior e de forma associada com lâminas de especies com maior resistencia mecânica nas capas. Abstract Production of plywood using veneers of Sequoia Sempervirens and urea-formaldehyde resin. This research was carried out to evaluate the quality of plywood made from wood veneer of Sequoia Sempervirens. It was produced in laboratory plywood composed by five veneers with 2.0 mm thick, bonded with urea-formaldehyde resin (UF) with two different formulations of glue and amount of glue spread. The panels were pressed with specific pressure of 10 kgf/cm², temperature of 110 °C and pressing time of 10 minutes. It was evaluated the properties of the glue line shear strength (RLC) and static bending (MOE and MOR) parallel and perpendicular. In general, the different adhesive formulations and amount of spread glue did not significantly affect the results of the properties of the panels, which represent an important aspect on the economic point of view. The mean values of RLC and percentage of wood failure meet minimum requirements of standard EN 314-2 (1993). The results of this research revealed the possibility to using the veneers of Sequoia for the core of internal use plywood associated with greater strength species on the faces. Keywords: Wood veneer; Sequoia; plywood; urea-formaldehyde.
