Studies on the Content of Free Amino Acids in Needles of Undamaged and Damaged Spruce Trees at a Natural Habitat

Summary Measurements of the amino acids in needles of undamaged and damaged 90-year-old spruce trees ( Picea abies ) showed different patterns. During the summer months a reduction in total amino acid content of about 60 % was found. In autumn the content of total amino acids rose again. The courses of the single amino acids behave similarly to that of the total amino acids. Quantitatively, the main amino acids were GLU, ASP and GLN with about 37 %, 21 % and 10 %, respectively, followed by PRO, ALA and SER with about 3–4 % each. In the needles of healthy trees large variations in ARG content could be observed. These variations correlate neither with the damage degree of the trees nor with t…