Effects of Organic Planting Method on Quality and Safety of Tobacco Leaves

In order to explore the influence of organic planting method on quality and safety of tobacco leaves,experiments were conducted in Lawu County,Dali of Yunnan Province for 3 years.Agricultural characters,yield of flue-cured tobacco and the content of 5 kinds of metal in tobacco leaves and cigarette were investigated.The results showed that the yield of flue-cured tobacco was less affected among years,but the proportion of supper and middle grade tobacco leaves was decreased under organic planting method in 3 years continuous cropping.The content of Hg in tobacco leaf was different in 3 years,but the content of As were increased,and the content of Pb,Cd and Cr showed a decreasing tendency.The content of above 5 kinds of metal varied according to the leaf position,Hg content was higher in the upper and the lower leaf while much lower content in the middle leaf,the content of As was the upper leaf the middle leafthe lower leaf,the contend of Cd was the middle leafthe upper leafthe lower leaf;the content of Pb was the lower leaf the upper leaf,and the content of Cr was the upper leaf the middle leaf the lower leaf.The content of Pb,Cd and Cr in cigarette sample was much lower than that of in flue-cured tobacco leaves.The results suggested that organic planting method was an alternative way for removal harmful components in cigarette smoke.