Many plant species respond to the abiotic stress by formation of volatile organic compounds (VOCs). Such abiotic stress could be light, temperature, atmospheric CO2 or nutrition. Due to the climatic change, vineyards are subjected to abiotic stress, inducing changes of constitutive VOCs either by stimulating or quenching of their emissions. Volatile terpenes are of particular interest as in case of isoprene only de novo biosynthesis occurs, while some monoterpenes are also stored within the plant. Recently, a role of isoprene and monoterpenes in the plant protection against abiotic stresses have been proposed. Many studies have been concentrating on isoprene as this is the most emitted hydrocarbon by plants into the atmosphere. Grapevine has not been reported to emit isoprene, but some varieties do emit monoterpenes. This work focus on understanding the role of monoterpenes in grapevine protection against acute heat stress episodes. The VOCs emission will be characterised by Proton Transfer Reaction-Mass Spectrometry (PTRMS) of two different grapevine genotypes, Chardonnany 130 and Chardonnany 890, under heat stress. These two genotypes present a unique case since they are genetically identical apart from a difference in the DXS gene, regulating monoterpene biosynthesis. The experiments will be done in collaboration with the Fondazione Edmund Mach of San Michele all’Adige.