Analysis of Phenolics of Bud Exudates of Populus Cathayana and Populus Szechuanica by GC-MS

Analysis of GC-MS data revealed 58 com ponents of bud exudate from P. cathayana (Section Tacamahaca) and 40 components of bud exudate from P. szechuanica (Section Tacamahaca) of which 47 and 35 respectively were phenolics. The bud exudates were very similar in composition, containing flavanones and chalcones (61% and 51% respectively), flavones (15% and 12%) and pentenyl caffeates (11% and 6%). The major single component of the exudate of both poplars was pinobanksin- 3-acetate (26% and 33%). The bud exudates of P. cathayana and P. szechuanica are similar to those of European and American Section Aigeiros poplars and unlike those of North American Section Tacamahaca poplars.