Comparative analysis of stilbene concentration in grapevine shoots of thirteen Vitis during a three-year study

Abstract

Grapevine shoots are considered one of the most important by-products of vineyards with a production between 2 and 5 tons/year/hectare. They have a variety of applications according to their content of compounds of interest, such as polyphenols, proteins and stilbenes. Stilbenes are extremely valuable compounds for the plant kingdom and the population due to their anti-microbial, anti-fungal, antioxidant and anti-cancer properties, among others. The stilbene concentration in grapevine shoots is influenced by many factors, the most important being species and climate conditions. The present research studies the influence of both factors on the stilbene concentration in grapevine shoots. To this end, the grapevine shoots from thirteen Vitis were collected for three years. A total of thirteen stilbenes were quantified by HPLC-DAD. The results showed the influence of the Vitis species on the stilbene concentration. In addition, climate conditions also proved to be an influential factor, adverse conditions like high temperatures, high solar radiation, high evapotranspiration, and/or low humidity being the ideal conditions for stilbene production, whereas conditions related to increased humidity (rainfall and relative humidity) extended the dimer stilbene production, as they may facilitate the response to the fungal stress.