Seasonal variations in the leaf surface composition of field grown grapevine plants

The leaf surface is the first barrier of grapevine plants towards various environmental stressors causing damage in vineyards. For this reason, identification of leaf surface metabolites in grapevine and their putative role in plant–environment interactions is important for viticulture. In this study, the leaf surface components of 16 grapevine plants (Vitis vinifera) growing in an experimental vineyard were analyzed in two consecutive seasons – the summer and the autumn of 2007. Forty-eight individual metabolites typical of the cuticular plant wax were identified by gas chromatography–mass spectrometry (GC– –MS). They belonged to the following groups of compounds: hydrocarbons, sterols, terpenes, free and esterified fatty acids, alcohols, aldehydes and ketones. The metabolic profiles of the summer and the autumn samples were statistically different (P < 0.05), which was mainly attributed to the specific insects present in the two seasons and to the adaptation of the grapevine to lower temperatures.