Abstract
The effect of four grapevine training systems (cordon height 0.4, 0.8, 1.2 and 1.6 m) on the parameters of canopy architecture, leaf area, leaf index, water loss through transpiration, activity of the photosynthetic apparatus, crop productivity and yield of wine grape cultivar ‘Aromatnyi’ (Vitis vinifera L.) was examined. It is shown that the vertical shoot positioning on cordon heights of 0.4 m and 0.8 m increases the photosynthetic capacity, but the crop productivity potential is realized only in years with less drought. Free-growing on cordons at a height of 1.2 m, provides a sufficiently high crop productivity potential at relatively low water loss through transpiration. Downward hanging shoots on cordons at a height of 1.6 m reduces leaf area and shapes the canopy architecture with increased transpiration, increases the effect of water deficit and negatively impacts crop productivity. It was found that the optimization of the parameters of the canopy reduces the negative effect of water deficit and may help adapt grapevines to non-irrigated cultivation in a semi-arid climate. A reduction of water loss through transpiration in phases of water stress leads to an increase of photosynthetic activity and crop productivity.