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Registro Completo |
Biblioteca(s): |
Embrapa Milho e Sorgo. |
Data corrente: |
29/08/2019 |
Data da última atualização: |
24/01/2020 |
Tipo da produção científica: |
Artigo em Periódico Indexado |
Autoria: |
REIS, C. O. dos; MAGALHAES, P. C.; AVILA, R. G.; ALMEIDA, L. G.; RABELO, V. M.; CARVALHO, D. T.; CABRAL, D. F.; KARAM, D.; SOUZA, T. C. de. |
Afiliação: |
Caroline Oliveira dos Reis, Universidade Federal de Alfenas; PAULO CESAR MAGALHAES, CNPMS; Roniel Geraldo Avila, Universidade Federal de Lavras; Lorena Gabriela Almeida, Universidade Federal de Lavras; Valquíria Mikaela Rabelo, Universidade Federal de Alfenas; Diogo Teixeira Carvalho, Universidade Federal de Alfenas; Daniela Ferreira Cabral, Universidade Federal de Alfenas; DECIO KARAM, CNPMS; Thiago Correa de Souza, Universidade Federal de Alfenas. |
Título: |
Action of N-succinyl and N,O-dicarboxymethyl chitosan derivatives on chlorophyll photosynthesis and fluorescence in drought-sensitive maize. |
Ano de publicação: |
2019 |
Fonte/Imprenta: |
Journal of Plant Growth Regulation, v. 38, p. 619-630, 2019. |
DOI: |
10.1007/s00344-018-9877-9 |
Idioma: |
Inglês |
Conteúdo: |
Chitosan induces plant tolerance to various abiotic stresses, including water deficit. However, its use may be limited, due to its constitution and low solubility in water. Thus, chemical modifications were proposed in this study with the objective of potentializing its biological effects in maize plants. The derivatives were semi-synthesized (N-succinyl and N,O-dicarboxymethyl) and, together with chitosan, they were applied, via the leaf, in a drought-sensitive maize hybrid (BRS1030) under pre-flowering water deficit. The water deficit was maintained for 15 days and the analyses were performed at the beginning and end of stress, and also in rehydration. Leaf water potential, gas exchange, chlorophyll fluorescence, and content of chloroplastidic pigments were evaluated. The use of the derivatives modulated photosynthesis parameters, affecting the involved mechanisms, such as stomatal activity, water use efficiency and photosystem II activity. Chlorophyll fluorescence indicated that the antenna complex was damaged by the water deficit condition, with a decrease in the energy flux in the electron transport chain and in the photochemical phase of photosynthesis. However, the spraying of chitosan derivatives induced tolerance to water deficit, suggesting that chitosan derivatives are more bioavailable to plants. Water stress decreases pigment content, but both the application of chitosan and derivatives increased these contents. It is concluded that chitosan derivatives improved the photosynthetic parameters in maize susceptible to drought, inducing tolerance to this stress, and the possible reasons and consequences are discussed. MenosChitosan induces plant tolerance to various abiotic stresses, including water deficit. However, its use may be limited, due to its constitution and low solubility in water. Thus, chemical modifications were proposed in this study with the objective of potentializing its biological effects in maize plants. The derivatives were semi-synthesized (N-succinyl and N,O-dicarboxymethyl) and, together with chitosan, they were applied, via the leaf, in a drought-sensitive maize hybrid (BRS1030) under pre-flowering water deficit. The water deficit was maintained for 15 days and the analyses were performed at the beginning and end of stress, and also in rehydration. Leaf water potential, gas exchange, chlorophyll fluorescence, and content of chloroplastidic pigments were evaluated. The use of the derivatives modulated photosynthesis parameters, affecting the involved mechanisms, such as stomatal activity, water use efficiency and photosystem II activity. Chlorophyll fluorescence indicated that the antenna complex was damaged by the water deficit condition, with a decrease in the energy flux in the electron transport chain and in the photochemical phase of photosynthesis. However, the spraying of chitosan derivatives induced tolerance to water deficit, suggesting that chitosan derivatives are more bioavailable to plants. Water stress decreases pigment content, but both the application of chitosan and derivatives increased these contents. It is concluded that chitosan derivatives improved... Mostrar Tudo |
Palavras-Chave: |
Bioestimulante; Déficit hídrico; Potencial hídrico foliar; Trocas gasosas. |
Thesagro: |
Milho. |
Categoria do assunto: |
S Ciências Biológicas |
URL: |
https://ainfo.cnptia.embrapa.br/digital/bitstream/item/201386/1/Action-N-succinyl.pdf
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Marc: |
LEADER 02553naa a2200289 a 4500 001 2111698 005 2020-01-24 008 2019 bl uuuu u00u1 u #d 024 7 $a10.1007/s00344-018-9877-9$2DOI 100 1 $aREIS, C. O. dos 245 $aAction of N-succinyl and N,O-dicarboxymethyl chitosan derivatives on chlorophyll photosynthesis and fluorescence in drought-sensitive maize.$h[electronic resource] 260 $c2019 520 $aChitosan induces plant tolerance to various abiotic stresses, including water deficit. However, its use may be limited, due to its constitution and low solubility in water. Thus, chemical modifications were proposed in this study with the objective of potentializing its biological effects in maize plants. The derivatives were semi-synthesized (N-succinyl and N,O-dicarboxymethyl) and, together with chitosan, they were applied, via the leaf, in a drought-sensitive maize hybrid (BRS1030) under pre-flowering water deficit. The water deficit was maintained for 15 days and the analyses were performed at the beginning and end of stress, and also in rehydration. Leaf water potential, gas exchange, chlorophyll fluorescence, and content of chloroplastidic pigments were evaluated. The use of the derivatives modulated photosynthesis parameters, affecting the involved mechanisms, such as stomatal activity, water use efficiency and photosystem II activity. Chlorophyll fluorescence indicated that the antenna complex was damaged by the water deficit condition, with a decrease in the energy flux in the electron transport chain and in the photochemical phase of photosynthesis. However, the spraying of chitosan derivatives induced tolerance to water deficit, suggesting that chitosan derivatives are more bioavailable to plants. Water stress decreases pigment content, but both the application of chitosan and derivatives increased these contents. It is concluded that chitosan derivatives improved the photosynthetic parameters in maize susceptible to drought, inducing tolerance to this stress, and the possible reasons and consequences are discussed. 650 $aMilho 653 $aBioestimulante 653 $aDéficit hídrico 653 $aPotencial hídrico foliar 653 $aTrocas gasosas 700 1 $aMAGALHAES, P. C. 700 1 $aAVILA, R. G. 700 1 $aALMEIDA, L. G. 700 1 $aRABELO, V. M. 700 1 $aCARVALHO, D. T. 700 1 $aCABRAL, D. F. 700 1 $aKARAM, D. 700 1 $aSOUZA, T. C. de 773 $tJournal of Plant Growth Regulation$gv. 38, p. 619-630, 2019.
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Embrapa Milho e Sorgo (CNPMS) |
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Biblioteca(s): |
Embrapa Florestas. |
Data corrente: |
06/09/2017 |
Data da última atualização: |
05/01/2018 |
Tipo da produção científica: |
Artigo em Anais de Congresso |
Autoria: |
CLARO, F. C.; MATOS, M. de; MAGALHAES, W. L. E. |
Afiliação: |
Francine C. Claro, UFPR; Mailson de Matos, Estudantes PHD, UFPR; WASHINGTON LUIZ ESTEVES MAGALHAES, CNPF. |
Título: |
Effect of the hemicellulose in the properties of nanopaper. |
Ano de publicação: |
2017 |
Fonte/Imprenta: |
In: INTERNATIONAL SYMPOSIUM ON WOOD, FIBRE AND PULPING CHEMISTRY, 19., 2017, Porto Seguro. Proceedings. Viçosa, MG: UFV, 2017. |
Páginas: |
p. 393-397. |
Idioma: |
Inglês |
Conteúdo: |
The foldable, low thermal expansion, and optically transparent are main properties of paper produced with cellulose nanofibers (nanopaper), being able to be used ifl the development of flexible circuit technologies. In this context, this work evaluates the importance of hemicellulose in the properties of nanofiber paper (NFP). The hemicellulose extraction from Pinus sp bleached cellulose pulp was performed with NaOH 17.5% for 1.5 h. Thereafter, the pulp was washed with 8.3% NaOH, then was add 10% acetic acid until neutralization, and washed with water. The nanofibrils were obtained by mechanical defibrillation in a Super Masscoloider Masuko Sangyo mill. The NFP with the grammage of 40 and 50 g/m2 were produced by filtration and drying under pressure. The extraction process reduced 80% of xylose, 40% of mannose and 40% of galactose compared of the bleached cellulosic pulp. The NFPs with around 15% of hemicellulose are homogeneous and transparent, the interstices between the fibers, observed by scanning electron microscopy, are small enough to avoid light scattering, making the cellulosic material transparent. The NFP of 40 and 50 g/m2 had a thickness of 45 J..Im,water absorption of 63 and 34 g/m2, respectively. They did not present air permeability. NFP of 40 and 50 g/m2 without hemicellulose had a thickness of 76 and 87 um, water absorption of 128 g/m2 and air permeability of 202 and 384 s/100 em", respectively. The spaces created by the coalescence of the cellulose nanofibrils after the extraction of the hemicellulose result in the dispersion of the light and consequently in the opacity of the NFP. Extraction of hemicellulose reduced the tensile and bursting strength by 80%. Therefore, hemicellulose acts as an inhibitor of the coalescence of microfibrils, providing adhesion and increase of the mechanical properties. MenosThe foldable, low thermal expansion, and optically transparent are main properties of paper produced with cellulose nanofibers (nanopaper), being able to be used ifl the development of flexible circuit technologies. In this context, this work evaluates the importance of hemicellulose in the properties of nanofiber paper (NFP). The hemicellulose extraction from Pinus sp bleached cellulose pulp was performed with NaOH 17.5% for 1.5 h. Thereafter, the pulp was washed with 8.3% NaOH, then was add 10% acetic acid until neutralization, and washed with water. The nanofibrils were obtained by mechanical defibrillation in a Super Masscoloider Masuko Sangyo mill. The NFP with the grammage of 40 and 50 g/m2 were produced by filtration and drying under pressure. The extraction process reduced 80% of xylose, 40% of mannose and 40% of galactose compared of the bleached cellulosic pulp. The NFPs with around 15% of hemicellulose are homogeneous and transparent, the interstices between the fibers, observed by scanning electron microscopy, are small enough to avoid light scattering, making the cellulosic material transparent. The NFP of 40 and 50 g/m2 had a thickness of 45 J..Im,water absorption of 63 and 34 g/m2, respectively. They did not present air permeability. NFP of 40 and 50 g/m2 without hemicellulose had a thickness of 76 and 87 um, water absorption of 128 g/m2 and air permeability of 202 and 384 s/100 em", respectively. The spaces created by the coalescence of the cellulose nanofibr... Mostrar Tudo |
Palavras-Chave: |
Air permeability; Bleached pulp; Nanofibra; Permeabilidade do ar. |
Thesagro: |
Hemicelulose. |
Thesaurus NAL: |
Hemicellulose; Nanofibers; Tensile strength. |
Categoria do assunto: |
X Pesquisa, Tecnologia e Engenharia |
URL: |
https://ainfo.cnptia.embrapa.br/digital/bitstream/item/163592/1/2017-Washington-ISWFPC-Effect.pdf
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Marc: |
LEADER 02596nam a2200241 a 4500 001 2075217 005 2018-01-05 008 2017 bl uuuu u00u1 u #d 100 1 $aCLARO, F. C. 245 $aEffect of the hemicellulose in the properties of nanopaper.$h[electronic resource] 260 $aIn: INTERNATIONAL SYMPOSIUM ON WOOD, FIBRE AND PULPING CHEMISTRY, 19., 2017, Porto Seguro. Proceedings. Viçosa, MG: UFV$c2017 300 $ap. 393-397. 520 $aThe foldable, low thermal expansion, and optically transparent are main properties of paper produced with cellulose nanofibers (nanopaper), being able to be used ifl the development of flexible circuit technologies. In this context, this work evaluates the importance of hemicellulose in the properties of nanofiber paper (NFP). The hemicellulose extraction from Pinus sp bleached cellulose pulp was performed with NaOH 17.5% for 1.5 h. Thereafter, the pulp was washed with 8.3% NaOH, then was add 10% acetic acid until neutralization, and washed with water. The nanofibrils were obtained by mechanical defibrillation in a Super Masscoloider Masuko Sangyo mill. The NFP with the grammage of 40 and 50 g/m2 were produced by filtration and drying under pressure. The extraction process reduced 80% of xylose, 40% of mannose and 40% of galactose compared of the bleached cellulosic pulp. The NFPs with around 15% of hemicellulose are homogeneous and transparent, the interstices between the fibers, observed by scanning electron microscopy, are small enough to avoid light scattering, making the cellulosic material transparent. The NFP of 40 and 50 g/m2 had a thickness of 45 J..Im,water absorption of 63 and 34 g/m2, respectively. They did not present air permeability. NFP of 40 and 50 g/m2 without hemicellulose had a thickness of 76 and 87 um, water absorption of 128 g/m2 and air permeability of 202 and 384 s/100 em", respectively. The spaces created by the coalescence of the cellulose nanofibrils after the extraction of the hemicellulose result in the dispersion of the light and consequently in the opacity of the NFP. Extraction of hemicellulose reduced the tensile and bursting strength by 80%. Therefore, hemicellulose acts as an inhibitor of the coalescence of microfibrils, providing adhesion and increase of the mechanical properties. 650 $aHemicellulose 650 $aNanofibers 650 $aTensile strength 650 $aHemicelulose 653 $aAir permeability 653 $aBleached pulp 653 $aNanofibra 653 $aPermeabilidade do ar 700 1 $aMATOS, M. de 700 1 $aMAGALHAES, W. L. E.
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