Influência do regime hídrico e da rega no comportamento da casta Touriga Nacion...

• Author(s): Rodrigues, Pedro
• Date: 2011
• Persistent ID: http://hdl.handle.net/10400.5/3874
• Origin: Repositório da UTL
• Subject(s): vitis vinifera; irrigation; water stress indicators; transpiration; modelling; wine quality
• Document Type: Doctoral Thesis
• Language: Portuguese
• Advisor(s): Alves, Isabel Maria Lopes

Description

Doutoramento em Engenharia dos Biossistemas - Instituto Superior de Agronomia The main objective of this work was to evaluate the behaviour of cv “Touriga Nacional” when subjected to different water regimes, so as to determine the impacts of irrigation amount and irrigation scheduling on yield and quality of the respective musts in the Dão region. To characterize the water regime of the vines, available soil water was monitored throughout the several crop developmental stages, as well as several plant based indicators of water stress (leaf and stem water potential, stomatal resistance, surface radiometric temperature). Vegetative growth, yield and must quality were determined at harvest. A two-layer model, based on meteorological data and measured surface radiative temperature, was built and calibrated in order to estimate the partition of the energy balance of the canopy (vines + undercover/soil) and its components, during the growth and maturation phase of the grapes. It allows a good estimation of daily transpiration of the vines, which can therefore be used to better interpret the results obtained relative to the water stress indicators and yield and quality parameters. The results show that irrigation led to small differences between treatments, despite the different water depths applied in the different irrigation treatments, since plant transpiration during fruit formation and maturation was practically the same, due to the extraction of the soil water reserves by the deep root system.