Crop yield response to water - Cra

Lead AuthorSVictor O. Sadras(SARDI Waite Campus,Australia)Heinz R. Schultz(GRC, Geisenheim,Germany)GrapevineContributingAuthorsJoan Girona, Jordi Marsal(IRTA, Lleida, Spain)AcknowledgementsVS research in grapevinephysiology is funded by theRiver Murray ImprovementProgramme and theAustralian Grapes and WineResearch and DevelopmentCorporationIntroduction and BackgroundGrapevine is a long-lived deciduous crop traditionally grown in alatitudinal range between 30 o and 50 o . The geographical rangeof wine grapes includes the traditional European countries Italy,France and Spain that account for most of world production, and othercountries where the industry has achieved different degrees of maturity(Figure 1). The crop is expanding into new areas in countries with anincipient industry; in 2000, Denmark was accepted as a commercial wineproducing nation within the European Union and the Association of DanishWinegrowers had 1 400 members in 2009 (Bentzen and Smith, 2009).Tonietto and Carbonneau (2004) characterized worldwide macroclimatesfor viticulture using three indices: soil water balance over the growing cycle,solar radiation and temperature conditions, and night temperature duringmaturation relative to variety requirements, vintage and wine quality.Profitability of the wine industry is related to both production volumeand value per unit volume. The relative contribution of these two factorsranges from enterprises specializing in a high-volume approach to thosetargeting low-volume, high-value product. Trade-offs between high yieldand berry traits related to wine quality are not universal but are commonand may constrain the dual maximization of volume and value per unitvolume of production. The trade-off between yield and quality underliesregulations in some European countries where no irrigation is allowed forquality wine production. Accepting that wines attracting higher prices areoften from vines producing low to moderate yields, the critical questionfrom an irrigation viewpoint is how to manage irrigation to capture thebenefit of high yield while achieving a level of quality that maximizeseconomic returns.Thus, whereas the core of the grapevine crop remains in the temperatelatitudinal band, there is an increasing diversity of environments that,together with diverse production objectives and potential trade-offs dictatecontrasting water-management practices in the vineyard. Additionally,the grape and wine industries operate in a global context of competingagricultural and non-agricultural uses of scarce resources – chiefly land,water, and energy – increasing environmental concerns, and shifts inclimates and markets.460crop yield response to water