Effect of Mercury Stress on Physiological Characteristics of Flue-Cured Tobacco

A pot experiment was conducted to explore the effect of different mercury(Hg) concentration on physiological characteristics of flue-cured tobacco.The results indicated that the malondialdehyde(MDA)content,protective enzyme activity,cell membrane permeability of tobacco leaves,the cell membrane permeability and activity of tobacco roots were decreased with the increase of Hg concentration.The chlorophyll content of tobacco leaves increased first and decreased afterwards,lower concentration of Hg(0.5 mg/kg) had a promoting effect on the chlorophyll content of tobacco leaves at rosette stage.The activity of catalas(CAT) were the most sensitive physiological index affecting the flue-cured tobacco leaves under the Hg stress,which were in extreme negative correlation with the concentration of Hg.