Crop yield response to water - Cra

Current season inflorescences become visible several weeks after budburst. Flower cap fall andstamen release marks the full bloom stage (Stage 23 in Figure 2). Berries per bunch, the secondyield component, depend on number of flowers and berry set, which may be particularly affectedin some particular combinations of sites, seasons and cultivars, e.g. Chardonnay in cool conditions.As in most flowering plants, however, only a fraction of flowers set fruit, typically for grapevinethis is 20-50 percent.FIGURE 2 Major stages in the modified Eichhorn and Lorenz (E-L) phenological scale (from Coombe 1995).MAJOR STAGESE-LnumberALL STAGESIV BudburstXII Shoots 10 cmXIX Flowering, beginsXXIII Full bloomXXVII SettingXXXI Berries pea-sizeXXXV VeraisonXXXVIII HarvestInflorescence clear,5 leaves50% caps offYoung berries growingBunch at right anglesto stemBunches hangingdownBerry softening beginsBerry colouring beginsBerries ripeModified from Eich horn andLorenz 1977 by B.G. CoombeI Winter budII BudswellIII Woolly bud-brown wool visibleIV Green tip: first leaf tissue visibleV Rosette of leaf tips visibleVII First leaf separated from shoot tipIX 2 to 3 leaves separated; shoots 2-4 cm longXI 4 leaves separatedXII 5 leaves separated; shoots about 10 cmlong; inflorescence clearXIII 6 leaves separatedXIV 7 leaves separatedXV 8 leaves separated, shoot elongattingrapidly; single flowers in compact groupsXVI 10 leaves separatedXVII 12 leaves separated; inflorescence welldeveloped, single flowers separatedXVIII 14 leaves separated; flower caps still inplace, but cap colour fading from greenXIX About 16 leaves separated; beginning offlowering (first flower caps loosening)XX 10% caps offXXI 30% caps offXXIII 17-20 leaves separated: 50% caps offXXV 80% caps off (= full-bloom)XXVI cap-fall completeXXVII Setting: young berries enlarging (>2 mmdiam.), bunch at right angles to stemXXIX Berries pepper-corn size (4 mm diam.);bunches tending downwardsXXXI Berries pea-size (7 mm diam.)XXXII Beginning of bunch closure, berriestouching (if bunches are tight)XXXIII Berries still hard and greenXXXIV Berries begin to soften;Brix starts increasingXXXV Berries begin to colour and enlargeXXXVI Berries with intermediate Brix valuesXXXVII Berries not quite ripeXXXVIII Berries harvest-ripeXXXIX Berries over-ripeXXXXI After harvest; cane maturation completeXXXXIII Beginning of leaf fallXXXXVII End of leaf fallShoot and inflorescence development Flowering Berry development Ripening Senescence462crop yield response to water