不同打顶方式对烤烟吸收重金属的影响

Effect of topping on heavy metal absorption in flue-cured tobacco

为探讨烤烟重金属的调控措施,采用大田试验方法,研究了在土壤重金属复合污染的条件下,不同打顶方式对烤烟吸收重金属的影响。结果表明,处理B初花打顶正常留叶对叶部Cd、Pb、Cr(下部叶和中部叶)调控效果较好。在重金属复合污染条件下,烟株体内重金属Cd、Pb和Hg含量随叶位的升高而增加,Cr含量随叶位的升高而降低,根部含量最多;通过烟株对重金属吸收系数比较发现,Cd和Hg较易吸收,Pb和Cr不易吸收。处理B对中部叶和上部叶干物质积累率贡献最大。

Effects of topping on heavy metal absorption in flue-cured tobacco grown on heavyly polluted soil were assessed in field experiments.Results showed that topping at early flowering had better effects on controlling Cd、Pb and Cr absorption by the bottom and middle leaves.Under multiple polluted conditions,Cd,Pb,Hg content increased while Cr decreased with leaf position up-wards.Cr existed mainly in tobacco roots.The uptake coefficient analysis showed that Cd and Hg were more liable to be absorbed comparied with Pb and Cr.Treatment B was the biggest contributor to the accumulation rate of dry matter in upper and middle leaves.