Timing of Shoot Thinning in Vitis vinifera: Impacts on Yield and Fruit Composition Variables

摘要: Many growers in the Niagara Peninsula of Ontario are reluctant to use canopy division address high vigor their vineyards. An alternative approach delayed shoot thinning was explored. Pinot noir and Cabernet franc vines were subjected six different shoot-thinning timings, based on Eichhorn Lorenz phenological stages 9 31, during 2001 2002 seasons. additional double-prune treatment (retaining four canes at dormant pruning removing two fruit set) imposed franc. Minor differences between treatments observed with respect yield, periderm formation, vine size. However, study carried out primarily assess impact these berry, must, wine composition microclimate. Early resulted increased titratable acidity (TA) soluble solids berries must. generally higher color intensity berries, lower TA musts, intensity, total phenolics, anthocyanins wines. The characterized by solids, hue/tint, phenolics overall. Canopy assessment showed that after bloom produced leaf layer numbers better cluster exposure than did control early thinning, especially induced areas both cultivars compared later treatments. Double had no mean area or photosynthetic photon flux density. Despite reductions density, appeared lead concomitant delays maturity terms anthocyanins, phenolics.