Allelopathic Effect of Different Tobacco Varieties to Lettuce

The allelopathic potential of the root, stem and leaf of different flue-cured tobacco varieties were determined by sandwich method. The results showed that the allelopathy of different flue-cured tobacco had significant differences, its potential was leaf > stem > root, root length of lettuce > bud length, and allelopathy showed enhanced trend with the increase of consumption. The varieties Zhongyan100 and K326 showed strong allelopathy, NC102 and newly developed lines CF220 took the second place, and the NC89 and Yunyan87 showed weak allelopathy.