The influence of ageing on the amount and composition of phenolic compounds and their glucosides was studied in one to five-year-old shoots of Picea abies. The total content of phenolics increased remarkably within the first two years of growth. In this period cinnamic acid derivatives were dominating, but beginning with the end of the first vegetation period a dramatic increase of acetophenones was observed. Obviously at the end of the first vegetation period the cinnamic acid derivatives are

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... ubjected to oxidation resulting in an increase of acetophenones.