Effects of methyl jasmonate on the monoterpenes of Muscat Hamburg grapes and wine.

BACKGROUND The importance of monoterpenes in grapes and wines aroma has compelled researchers to focus on developing methods to increase their abundance. Recent research revealed that exogenous elicitors can increase the contents of these compounds. This study determined the effects of methyl jasmonate (MeJA) preharvest treatments on the monoterpenes profiles of Muscat Hamburg grapes and wine. RESULTS A total of 27 monoterpenes were identified for Muscat Hamburg grapes and wine. The contents of most of the monoterpenes (free and glycosylated forms) in the grapes and wine increased in response to MeJA. An analysis of the expression of the genes in the terpenoid biosynthesis pathway indicated that the related biosynthetic pathways were activated by MeJA. The transcript levels of some genes were consistent with monoterpene production, including VviCSLinNer, VviGwbOciF, VviPNRLin, VviGT14, and VviUGT85A1L1. The developmental expressions patterns of the VviPP2B1 and VviMYB24 transcription factor genes were positively correlated with monoterpene accumulation in ripening grapes. CONCLUSIONS Our results suggest that MeJA may be useful for improving the aroma quality of grapes and wines. This article is protected by copyright. All rights reserved.