The effect of salt stress on resveratrol and piceid accumulation in two Vitis vinifera L. cultivars

Abstract

Salinity is one of the most important abiotic stresses, especially in arid regions. Such devastating constraint is converted mainly to oxidative burst. Thus, plants have to develop strategies to scavenge salt-related regenerated oxidant molecules. In the present work, fully aged plants derived from two Vitis vinifera L. cultivars, the Tunisian autochthonous tolerant genotype Razegui and the salt sensitive Syrah, were analyzed regarding their short term response to 100 mM NaCl, in hydroponic cultures.The ratio [ASA/ASA ? DHA] was calculated on the basis of the oxidation of ascorbic acid (ASA) into dehydroascorbic acid (DHA) in leaves. Results proved that oxidative stress was generated. This led to the accumulation of malondialdehyde which referred to a lipid peroxidation mainly in the sensitive Syrah. In order to cope with these oxidative disturbances, trans-resveratrol as well as its glucosides trans-piceid and cis-piceid have been de novo synthesized in the sensitive variety. Razegui stilbene concentrations were presented here for the first time and unexpectedly did not show a very important variation during the salt elicitation.

Impact of Environmental Factors on Stilbene Biosynthesis

“…Morus alba L. and Rheum undulatum L. accumulate the glucosylated stilbenes mulberroside A (a diglucoside of oxyresveratrol) and rhapontin (a monoglucoside of rhapontigenin, also known as rhaponticin) [87] ( Figure 5). Significant amounts of cisand trans-piceid are accumulated in grapevine, both constitutively [40,88,89] and in response to pathogen attack [90,91] and to environmental stresses such as UV light [88,[92][93][94], salinity [95], and drought [96,97]. Numerous glycosyltransferases that produce glucose esters of hydroxybenzoic and hydroxycinnamic acids accept a broad spectrum of structurally similar substrates [98].…”

“…Another important abiotic stress is salinity. Salt stress represents a devastating constraint to plants' development processes and physiological homeostasis, causing membrane disorganization, cytoplasm alkalinization, ROS induction, transport perturbations, tissue proliferation, and perturbations to photosynthesis, ionic and ionic-related channels [95].…”

Phenolic composition of Tempranillo Blanco (Vitis vinifera L.) grapes and wines after biostimulation via a foliar seaweed application

“…Stilbenes are phytoalexins that are synthetized as glucosides in grapevines, in response to cryptogrammic disease affection . Accordingly, resveratrol derivatives can be considered as stress markers . Stilbenes are found mainly in grape skins, and therefore a greater content of these compounds may be released in wines .…”

“…9,10 Accordingly, resveratrol derivatives can be considered as stress markers. 11 Stilbenes are found mainly in grape skins, and therefore a greater content of these compounds may be released in wines. 7,11 Some external stimuli such as ultrasonication treatment, ultraviolet irradiation, macronutrients, fungicides and elicitors give rise to an increased stilbene concentration, including other phenolic compounds, in grape skins, musts and wines.…”

“…11 Stilbenes are found mainly in grape skins, and therefore a greater content of these compounds may be released in wines. 7,11 Some external stimuli such as ultrasonication treatment, ultraviolet irradiation, macronutrients, fungicides and elicitors give rise to an increased stilbene concentration, including other phenolic compounds, in grape skins, musts and wines. 12 During the last decade, the study of phenolic compounds has been increasing because of their importance in protection against the development of cancers, cardiovascular diseases, diabetes, osteoporosis and neurodegenerative diseases.…”