Impact of Early Leaf Removal on Yield and Fruit and Wine Composition of Vitis vinifera L. Graciano and Carignan

摘要: Early defoliation is a novel cultural practice for crop management in grapevines. The effects of timing (prebloom or fruit set) and method (manual mechanical) early on yield grape wine composition Vitis vinifera L. cv. Graciano Carignan grapevines were investigated. Leaf removal induced substantial increase both cluster exposure canopy porosity. Yield was significantly reduced by varieties. per shoot between 30 70% manual mechanical leaf prebloom. In varieties, postflowering ineffective at modifying set, number berries cluster, shoot. Botrytis incidence also removal. Prebloom allowed full recovery the leaf:fruit ratios to that seen nondefoliated vines. Grape soluble solids alcohol concentration not affected defoliation. Malic acid decreased with set. Genotype-environment interactions berry acidity variables such as titratable tartaric concentrations found. substantially increased anthocyanin phenol grapes Carignan, resulted heavier berries, which nevertheless had enhanced color. These results support hypothesis early-defoliated vines, relative growth various organs independently from absolute mass. Mechanical has potential be cost-effective technique control improve composition.