Revista Brasileira de Fruticultura
Print version ISSN 0100-2945
On-line version ISSN 1806-9967
MOTA, Clenilso Sehnen; AMARANTE, Cassandro Vidal Talamini do; SANTOS, Henrique Pessoa dos and ALBUQUERQUE, Jackson Adriano. Water supply, solar radiation and photosynthesis in 'Cabernet Sauvignon' grapevines under plastic covering . Rev. Bras. Frutic. [online]. 2009, vol.31, n.2, pp.432-439. ISSN 0100-2945. http://dx.doi.org/10.1590/S0100-29452009000200017.
The objective of this work was to assess the effects of translucent plastic overhead cover on light and water supply of vineyard and leaf chlorophyll content and photosynthesis in grapevines. Five-year-old 'Cabernet Sauvignon' grapevines (Vitis vinifera L.) grafted on Paulsen 1103 rootstock and raised as 'Y' management system were used. The experiment followed a randomized block design, with two treatments (uncovered and covered plants) and four replicates of 15 plants (experimental unit). The plastic cover reduced the supply of ultraviolet (UV), blue, green, red, far red, and total (300-750 nm) radiation to the plants, as well as the water availability at the superficial soil layers (0-30 cm). Covered plants had higher values of maximum photosynthesis and leaf stomatal conductance than uncovered ones. The values for light compensation and saturation points, apparent quanta efficiency, dark respiration, leaf chlorophyll content, and basal leaf water potential were not affected by the use of plastic cover. The plastic covering reduced the light supply and water availability at the superficial soil layers, but improved leaf assimilation of CO2.
Keywords : Vitis vinifera L.; plasticulture; light spectrum; water potential; leaf chlorophyll content; CO2 leaf assimilation.