A slight temperature increase modulates changes in physiology and grape quality of two commercial vines of central Chile

Abstract

Current climate change sceneries represent a menace for grapevine production. Models have estimated than in the middle of the century temperature will increase aprox. 2°C. Considering this, it is relevant to identify the effects of temperature increase on commercial vineyards for improving the agricultural management in futures climate change sceneries. The aim of this study was to evaluate a slight temperature increase on grapevine physiology and grape quality in two varieties: Cabernet sauvignon (CS) and Syrah (Sy). In order to achieve the temperature increase, polycarbonate panels were used, emulating an “inverted funnel” under the vines canopy. Soil and panel structure produce a hot air concentration that fluid to the canopy by the top of structure (open chamber). It was possible to observe an increase on 1°C on canopy temperature and more that 2°C in soil temperature. Maximum temperature of canopy was 3.5°C superior and leaf temperature was increase in a medium of 1°C at midday at veraison. Although the increase was slight, plant exhibited significant effects. Phenology showed a decreased time from veraison to maturity in both varieties under temperature increase. At harvest, water potential was different depending of the variety: in Sy no differences were observed, but in CS was decrease in -0.13 Mpa. Also, in Sy, total soluble solids were increase on 2.5°Brix. In conclusion, a slight increase of temperature can modulate plant physiology and grape quality, thus can be considered for future sceneries of climate change.