不同类型土壤的烟株对铅的吸收与分配特征

Distribution and absorption of flue-cured tobacco to Pb in different types of soil

采用盆栽试验方法,研究了不同类型土壤中的烟株对铅的吸收及其体内分配特征.结果表明,铅添加水平在0.5g/kg以下时对烤烟生长影响较小,小于0.5g/kg时有促进作用,但大于等于0.5g/kg有一定抑制作用.烟株能大量积累铅,主要积累于根部.未添加铅时,烤烟铅含量从大到小依次为红壤、紫色土、水稻土,红壤富集铅能力最强;在铅添加水平为0.2～0.5g/kg时,烤烟铅含量从大到小依次为水稻土、红壤、紫色土.随着铅添加量的增大,烟株各器官铅含量逐渐升高,但增长率呈下降趋势,铅在烟叶和烟花的分配率不断降低.

Distribution and absorption of flue-cured tobacco to Pb in different types of soil were studied through a pot experiment. The results showed that amount of Pb under 0.5 g/kg had little effect on the growth of flue-cured tobacco, concentration lower than 0.5 g/kg promoted its growth advanced, but concentration higher than 0.5 g/kg retarded its growth. Meanwhile, it accumulated abundant Pb in the root of tobacco. Without Pb application, Pb contents of tobacco was red soil, purple soil, paddy soil （from high to low）, and tobacco was tolerant to Pb in red soil, with application from 0.2 to 0.5 g/kg, the order was paddy soil, red soil, purple soil, and tobacco was tolerant to Pb in paddy soil. With the increasing account of Pb application, its Pb content of tobacco increased correspondently, but the rate of increasing was decreasing. Simultaneously, the Pb content in tobacco＇s root and stem increased, but its distribution was low in the leaf and flower.