Data/hora: 08/06/2024 10:20:57

Provedor de dados: | 61
País: | Brazil
Título: | Photosynthesis and cell respiration modulated by water deficit in grapevine (Vitis vinifera L.) cv. Cabernet Sauvignon
Autores: | Martim,Sílvia A.; Santos,Mirella P.; Peçanha,Anderson L.; Pommer,Celso; Campostrini,Eliemar; Viana,Alexandre P.; Façanha,Arnoldo R.; Bressan-Smith,Ricardo.
Data: | 2009-01-01
Ano: | 2009
Palavras-chave: | Vitis vinifera; Drought tolerance; Irrigation management; Respiratory chain regulation; Plant bioenergetics.
Resumo: | Winegrape productivity and quality has been related to the regulated deficit irrigation, with important implications for the plant bioenergetics. When water deficit is imposed to grapevine plants, alterations in overall photosynthesis and cell respiration are observed. The aim of this study was to assess the modulations promoted by water stress on photosynthesis and respiration in leaves of the cv. Cabernet Sauvignon (cv. CS) for better understanding the physiological responses related to its drought tolerance and quality improvement under water deficit. For this purpose, measurements of photosynthetic efficiency, leaf water potential, gas exchange and O2 consumption were carried out. Leaf water potential, photosynthesis, stomatal conductance, transpiration and internal carbon concentration were significantly reduced upon stress, suggesting that plants of cv. CS present higher water use efficiency (A N/E) and lower carboxylative capacity (A N/Ci) under this condition. On the other hand, cell respiration increased more than 70 % as estimated by the increase of O2 consumption measured 12 days after suspension of irrigation. Most of this effect was related to a four-fold increase of the mitochondrial alternative oxidase (AOX) activity. These data indicate a key role for the AOX pathway in the physiological responses of grapevines to water deficit, and it implies that analyses of the AOX activation patterns should be useful for programs aiming to improve the consistency of fruit production and quality of winegrape cultivars by regulated deficit irrigation.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202009000200002
Editor: | Brazilian Journal of Plant Physiology
Relação: | 10.1590/S1677-04202009000200002
Formato: | text/html
Fonte: | Brazilian Journal of Plant Physiology  v.21 n.2 2009
Fonte: | info:eu-repo/semantics/openAccess