Anti-transpirant effects on grape physiology and berry and wine composition of Aglianico and Falanghina (Vitis vinifera L.) cultivars grown in Southern Italy

Abstract

In the last few decades the trend of increasing global temperatures has affected the accumulation of sugars in berries and hence the alcohol degree of wines. Numerous studies have considered different agronomic practices that limit photosynthetic activity and therefore the accumulation of sugars in the berry. The aim our study was to evaluate the effect of a natural anti-transpirant on grapevine physiology and berry and wine composition on two cultivars. In 2013 and 2014, in South Italy, Aglianico and Falanghina vines were treated at veraison with the anti-transpirant Vapor Gard® (T) and compared with a control (C) sprayed just with water. On each cultivar a bunch thinning (BT) was also applied both on the plants treated with Vapor Gard® and control. The data regarding following characters were collected and analyzed: production and number of bunches per plant, TSS, pH, TA, polyphenols, anthocyanins. The effectiveness of the film terpene was evaluated by gas exchange measurements (net photosynthesis, transpiration) using a portable photosynthesis system (LI-6400). The results demonstrate that the application of anti-transpirant has reduced the net photosynthesis rate (25-40%), stomatal conductance (40-60%), accumulation of sugars in berries (2 °Brix) and degrees alcohol (0.9-1.6 %vol.) in the wines produced. No significant differences between treatments were observed on other chemical components of the berries and wine measured.