IR-SNOM ANALYSIS OF OCCLUDING SUBSTANCES IN LUMINA OF XYLEM ELEMENTS IN SAPWOOD OF QUERCUS SERRATA INFECTED WITH RAFFAELEA QUERCIVORA

摘要

We directly analyzed occluding deposits in xylem elements of Quercus serrata produced as a defense response of sapwood against fungi. Occluding substances about 10 μm across were analyzed by IR-SNOM (Infrared-Scanning Near-field Optical Microscopy) which was able to measure IR spectrum with high spatial resolution. In such obtained near-field IR spectrum of occluding substances was hardly seen the C-H absorption band which should appear at 30002850 cm~1. On the other hand, the absorption band of ester bond exhibited very strong peak. Among the near-field IR spectra of related compounds, the similar ester absorption peak was observed in the spectrum of pectin and tannic acid. The presence of C-H absorption band as a very week peak was similar to (+)catechin and tannic acid.