Author
 |
Shellie, Krista |
|
Submitted to: Groupe d'Etude des Systèmes de Conduite de la Vigne
Publication Type: Abstract Only Publication Acceptance Date: 2/2/2005 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: Vine water stress during berry development is thought to impact wine quality through reduction in berry size and/or enhancement of berry quality components. The objective of this research was to determine how the magnitude and timing of vine water stress impacts vine yield components and berry and wine composition, and to use this information to develop an optimum water management strategy for warm, semi-arid production regions. A 1-acre trial consisting of sixteen, 56-vine plots was established in southern Idaho in spring 2002 within a commercial, 30-acre block of own-rooted, five-year-old ‘Merlot’. Weekly irrigations during 2002, ‘03, and ‘04 were varied in duration to provide vines, from bloom to harvest, with 100, 70, or 35 percent of full vine evapotranspiration (FVET), or 35 percent of FVET from bloom until veraison and then 70% FVET until harvest (35-70). The greatest vine water stress (35% FVET) was consistently associated with lowest yield. Vine water stress was also associated with reduced annual trunk and cordon growth, higher canopy transmission of photosynthetically active radiation (PAR), and a greater incidence of sunscald on exposed clusters. Wines produced from water stressed vines had greatest intensity (A420+A580). Results from this research support the dogma that vine water stress beneficially impacts berry components and leads to enhanced wine quality. However, the undesirable attributes observed in this trial, such as an increased incidence of sunscald on exposed clusters, decreased annual trunk growth, and a reduced number of clusters per vine, highlight the importance of defining the magnitude of water stress required to impart desired quality attributes. |
