Assessing the influence of partial canopy cover and temperature variability on late-season dehydration in grape berries

Abstract

Late-season dehydration (LSDN) is a physiological disorder affecting grape berry water content, resulting in dehydration. Vineyards in the Aegean Region of western Türkiye have experienced problems with LSDN, particularly during periods of high temperatures. This research examines how partial canopy covering materials affect temperature differentials inside and outside the canopy, including the determination of LSDN grape berries of Sultan 7 (Vitis vinifera L.). A partial shading net (PS) was employed to prevent LSDN in the grape berries, and shading net and polyethylene material (PSP) were deployed to assess the impact of increasing canopy temperatures on the occurrence of LSDN in grape berries. Although partial covering materials did not substantially affect grapevine yield, the control group produced the largest and the heaviest berries. In the second year, warmer conditions led to more clusters with LSDN-affected berries and increased sunburn damage on clusters. PS showed a high healthy cluster rate of 72.50%, while PSP and control showed lower rates of 63.60% and 58.10%, respectively. Throughout the study period, PS exhibited 9.02% LSDN berries, while the control and PSP showed 17.10% and 16.70% clusters with LSDN berries in the total harvested clusters, respectively. The study showed that PS treatment alleviated LSDN symptoms in clusters.