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Registro Completo |
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Biblioteca(s): |
Embrapa Mandioca e Fruticultura. |
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Data corrente: |
19/03/2004 |
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Data da última atualização: |
19/03/2004 |
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Autoria: |
HABERMANN, G.; MACHADO, E. C.; RODRIGUES, J. D.; MEDINA, C. L. |
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Afiliação: |
Universidade Estadual Paulista. |
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Título: |
CO2 assimilation, photosynthetic ligt response curves, and water relations of 'Pêra' sweet orange plants infected with Xylella fastidiosa. |
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Ano de publicação: |
2003 |
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Fonte/Imprenta: |
Brazilian Journal of Plant Physiology, Londrina, v. 15, n. 2, p. 79-87, 2003. |
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ISSN: |
1677-0420 |
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Idioma: |
Inglês |
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Conteúdo: |
Plants with citrus variegated chlorosis (CVC), a disease caused by the xylem-limited bactéria Xylella fastidiosa, have leaves with water deficiency symptoms and are associated with decreases on the net photosynthesis and transpiration rates. Using healthy and CVC-affected 'Pêra' sweet orange plants on 'Rangpur' lime rootstock, the leaf gas exchange variables were measured with an open-gas portable photosynthesis system. All plants were watered and the leaf water potencial (Yw) was measured by isopiestic thermocouple psychrometric technique. The net photosynthesis (A) vs. internal leaf CO2 concentration (A/Ci curves) was analyzed. The relative effect of stomatal resistance on photosynthesis (S%) and the estimation of carboxylation efficiency were calculated. The rates of photosynthesis and transpiration, stomatal conductance, and internal leaf CO2 concentration (Ci) were also measured while varying the photosynthetic photon flux density (PPFD). The S% values were approximately 30% greater in infected plants when compared to healthy ones. The light compensation point for diseased plants was higher than in the healthy ones, and the saturation light point in plants with CVC was twofold lower. The lower Yw in diseased plants favours the hypothesis of xylem occlusion, which probably caused a lower water supply to the mesophyll, thus decreasing the photosynthesis and transpiration rates. Nevertheless, there was also a reduction in the photosynthetic metabolic activities, represented by lower carboxylation efficiency and photochemical disturbances that were detected in diseased plants. MenosPlants with citrus variegated chlorosis (CVC), a disease caused by the xylem-limited bactéria Xylella fastidiosa, have leaves with water deficiency symptoms and are associated with decreases on the net photosynthesis and transpiration rates. Using healthy and CVC-affected 'Pêra' sweet orange plants on 'Rangpur' lime rootstock, the leaf gas exchange variables were measured with an open-gas portable photosynthesis system. All plants were watered and the leaf water potencial (Yw) was measured by isopiestic thermocouple psychrometric technique. The net photosynthesis (A) vs. internal leaf CO2 concentration (A/Ci curves) was analyzed. The relative effect of stomatal resistance on photosynthesis (S%) and the estimation of carboxylation efficiency were calculated. The rates of photosynthesis and transpiration, stomatal conductance, and internal leaf CO2 concentration (Ci) were also measured while varying the photosynthetic photon flux density (PPFD). The S% values were approximately 30% greater in infected plants when compared to healthy ones. The light compensation point for diseased plants was higher than in the healthy ones, and the saturation light point in plants with CVC was twofold lower. The lower Yw in diseased plants favours the hypothesis of xylem occlusion, which probably caused a lower water supply to the mesophyll, thus decreasing the photosynthesis and transpiration rates. Nevertheless, there was also a reduction in the photosynthetic metabolic activities, represe... Mostrar Tudo |
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Palavras-Chave: |
A/Ci curves; Citrus sinensis L; Osbeck; photosynthetic metabolism; photosynthetic photon flux density. |
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Thesaurus Nal: |
citrus variegated chlorosis; stomata. |
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Categoria do assunto: |
-- |
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Marc: |
LEADER 02415naa a2200253 a 4500
001 1651711
005 2004-03-19
008 2003 bl uuuu u00u1 u #d
022 $a1677-0420
100 1 $aHABERMANN, G.
245 $aCO2 assimilation, photosynthetic ligt response curves, and water relations of 'Pêra' sweet orange plants infected with Xylella fastidiosa.
260 $c2003
520 $aPlants with citrus variegated chlorosis (CVC), a disease caused by the xylem-limited bactéria Xylella fastidiosa, have leaves with water deficiency symptoms and are associated with decreases on the net photosynthesis and transpiration rates. Using healthy and CVC-affected 'Pêra' sweet orange plants on 'Rangpur' lime rootstock, the leaf gas exchange variables were measured with an open-gas portable photosynthesis system. All plants were watered and the leaf water potencial (Yw) was measured by isopiestic thermocouple psychrometric technique. The net photosynthesis (A) vs. internal leaf CO2 concentration (A/Ci curves) was analyzed. The relative effect of stomatal resistance on photosynthesis (S%) and the estimation of carboxylation efficiency were calculated. The rates of photosynthesis and transpiration, stomatal conductance, and internal leaf CO2 concentration (Ci) were also measured while varying the photosynthetic photon flux density (PPFD). The S% values were approximately 30% greater in infected plants when compared to healthy ones. The light compensation point for diseased plants was higher than in the healthy ones, and the saturation light point in plants with CVC was twofold lower. The lower Yw in diseased plants favours the hypothesis of xylem occlusion, which probably caused a lower water supply to the mesophyll, thus decreasing the photosynthesis and transpiration rates. Nevertheless, there was also a reduction in the photosynthetic metabolic activities, represented by lower carboxylation efficiency and photochemical disturbances that were detected in diseased plants.
650 $acitrus variegated chlorosis
650 $astomata
653 $aA/Ci curves
653 $aCitrus sinensis L
653 $aOsbeck
653 $aphotosynthetic metabolism
653 $aphotosynthetic photon flux density
700 1 $aMACHADO, E. C.
700 1 $aRODRIGUES, J. D.
700 1 $aMEDINA, C. L.
773 $tBrazilian Journal of Plant Physiology, Londrina$gv. 15, n. 2, p. 79-87, 2003.
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Registro original: |
Embrapa Mandioca e Fruticultura (CNPMF) |
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| Registros recuperados : 4 | |
| 2. |  | ALVAREZ, R. de C. F.; CRUSCIOL, C. A. C.; NASCENTE, A. S.; RODRIGUES, J. D.; HABERMANN, G. Gas exchange rates, plant height, yield components, and productivity of upland rice as affected by plant regulators. Pesquisa Agropecuária Brasileira, v. 47, n. 10, p. 1455-1461, out. 2012.| Tipo: Artigo em Periódico Indexado | Circulação/Nível: A - 2 |
| Biblioteca(s): Embrapa Arroz e Feijão; Embrapa Unidades Centrais. |
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| 3. | | ALVAREZ, R. de C. F.; HABERMANN, G.; CRUSCIOL, C. A. C.; NASCENTE, A. S.; RODRIGUES, J. D. Leaf gas exchange and yield of three upland rice cultivars. Bragantia, Campinas, v. 74, n. 1, p. 1-8, jan./mar. 2015.| Tipo: Artigo em Periódico Indexado | Circulação/Nível: A - 2 |
| Biblioteca(s): Embrapa Arroz e Feijão. |
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| 4. | | ALVAREZ, R. de C. F.; CRUSCIOL, C. A. C.; NASCENTE, A. S.; RODRIGUES, J. D.; HABERMANN, G.; PAIVA NETO, V. B. de. Trinexapac-ethyl affects growth and gas exchange of upland rice. Revista Caatinga, Mossoró, v. 29, n. 2, p. 320-326, abr./jun. 2016.| Tipo: Artigo em Periódico Indexado | Circulação/Nível: B - 1 |
| Biblioteca(s): Embrapa Arroz e Feijão. |
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| Registros recuperados : 4 | |
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| Nenhum registro encontrado para a expressão de busca informada. |
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