Effect of humic acid on the metabolism of tobacco

A test was carried out in Baofeng county,Henan Province from 1998 to 1999 which had humic acid as basic fertilizer of flue—cured tobacco in container.The result showed that humic acid could effectively improve the activity of some enzymes such as nitrate reductase,catalase,ascorbic acid oxidase,and polyphenol oxidase in the body of flue—cured tobacco.And the improved range is successively 1.98%～56.9%,25.9%～98.8%,20.4%～130.8%,and 8.6%～130.2%.The results indicate that humic acid can promote the metabolism of flue—cured tobacco,and raise the ability of resisting adversity.In tobacco body,as a result,the disease situation of tobacco mosaic and black shank is well controlled.