Abstract
This paper reports on the studies on the polyphenolic substances contained in the diseased leaves from paulownia tree affected with witches'-broom and in the healthy ones.
Polyphenolic substances in both of the healthy and the diseased leaves were determined by the method of paper chromatography, and tannin contents were estimated by the Löwenthal method. The results were as follows.
1. Chlorogenic acid took the greater part in the polyphenolic substances in both of the healthy and the diseased leaves.
2. Chlorogenic acid contents in the diseased leaves were about three times as much as that of healthy ones.
From these results, it was concluded that the possible cause of deep brown discloration of sap from the diseased leaves was due to the high contents of chlorogenic acid; it was suggested that certain part of the symptoms of the witches'-broom of paulownia tree was produced directly by the excess accumulation of chlorogenic acid.
