Surface leaf metabolites of two seedlings of a Bulgarian winemaking cultivar Storgozia I(1) were analyzed in two seasons - summer (July) and autumn (October). The resistance towards some fungal pathogens of one of the plants was estimated as superior to the resistance of the other one. Significant seasonal variations in the chemical constituents of the two seedlings were observed. The main metabolites of the summer samples were sterols, terpenes, fatty acids and heterocyclic compounds. In autumn, sterol and fatty acid contents decreased, mono- and diterpenes and heterocyclic compounds disappeared and instead of them hydrocarbons and alcohols were detected. Some individual components - stearic acid, alpha-amyrin, lupeol and squalene - correlated with the estimated resistance and were therefore proposed as biomarkers for the fungal resistance in grape-vine leaves.