Peroxidase Activities and Free Sugars in the Club－root and the Healthy Root Tissues of Cruciferous Plants

Peroxidase activities and free sugars in the club－root tissues of Chi－nese cabbage （Brassica pekinensis）and turnip（B.rapa）root were measured to investigate the physiological change of the disease. Peroxidase activities in the clab－root tissue were shown about 2 times greater than in the healthy root of Chinese cabbage by E_<TTORI>'s W_<ARBURG> manometric technique （Table 1）. Free sugars were determined by the paper chromatography, and sucrose, glucose and fructose were detected from both tissues of Chinese cabbage and turnip. It was found that sucrose was smaller in quantity in the club－root tis－sue of Chinese cabbage than in the healthy one, while glucose and fructosewere greater in quantity （Table 2）. Increase in activity of the peroxidase and the free reducing sugars in the diseased tissue may be deserving of abnormal hyperplasy of club－root.