Crop yield response to water - Cra

Figure 1 Grape production between 1990 and 2008 (FAO, 2011).1 2000EuropeItaly8 000FranceSpain4 000TurkeyProduction (thousands of tonne)08 0004 000OtherGermanyUSAChinaArgentinaChileAustraliaSouth AfricaIndiaBrazil1990 1995 2000 2005 2010YearStages of development in relation to yield determinationOverviewThe annual cycle of grapevine in temperate and cool environments includes a dormancy phase anda phase of active vegetative and reproductive development and growth. In tropical environments,vine physiological activity is continuous during the year. Figure 2 shows a scale accounting forphenological stages in temperate environments and Table 1 illustrates the range of key vegetativeand reproductive components of grapevines in vineyards with contrasting yield targets.After an overwintering period, when vegetative and reproductive buds remain dormant, visible leaftissue marks the beginning of budburst (Stage IV in Figure 2). Early shoot growth depends on plantreserves and is initially slow; it then accelerates in late spring. Parallel to root and vegetative shootgrowth, two important reproductive processes take place: (a) inflorescence primordia initiated inthe previous season resume growth, branching, branch elongation and flower formation, and (b)a new set of reproductive buds is induced and starts differentiation that will be completed in thefollowing season (Dunn, 2005). Bunch number is generally the largest source of seasonal and siterelatedvariation in grapevine yield (Tables 1 and 3).grapevine 461