甜高粱对土壤重金属Cd的吸收规律

Accumulation of heavy metal Cd in sweet sorghum

【目的】探讨甜高粱对土壤重金属Cd的吸收规律,筛选对重金属Cd具有富集能力的品种,为重金属Cd污染地区的环境修复提供理论依据。【方法】以辽甜1号和新高粱3号2种甜高粱幼苗为材料,采用盆栽试验研究土壤不同含量Cd(0,3,6,9,12mg/kg,以CdCl2.2.5H2O的形式外源加入)对甜高粱根、茎、叶等不同部位Cd含量及生长状况的影响。【结果】随着土壤中Cd含量的增加及Cd处理时间的延长,甜高粱根、茎、叶中的Cd含量总体呈增加趋势,不同处理之间Cd含量差异明显。2个甜高粱品种不同部位Cd含量由大到小均表现为:根>茎>叶,且2个甜高粱品种不同部位Cd含量之间也有明显差异。当用0～12mg/kg Cd处理相同时间时,辽甜1号体内积累的Cd含量较新高粱3号高。【结论】2种甜高粱品种对Cd的吸收能力存在着一定的差异,辽甜1号对土壤重金属Cd的吸收能力较新高粱3号强。

【Objective】 This study focused on exploring the absorption mechanism of Cd on sweet sorghum and selecting high sweet sorghum varieties with high accumulative ability to heavy metal Cd in order to provide a method for remediation of areas polluted by heavy metal.【Method】 Pot experiment was conducted to confirm the effects of soil Cd with different contents（0,3,6,9,12 mg/kg,external added as the form of CdCl2·2.5H2O）on Cd contents of leaves,roots and stems,and the physiological behaviors of two sweet sorghum varieties（Liaotian 1 and New sorghum 3）.【Result】 The Cd contents in leaves,roots and stems of two sweet sorghum varieties increased as the increase of Cd content added and the elongation of exposure time.There was significant difference in Cd contents between different treatments.For both varieties,roots contained the highest Cd contents,followed by stems and leaves.There was significant difference in Cd contents between different parts of the two varieties.When the treatment with Cd contents between 0-12 mg/kg,the accumulated Cd contents in Liaotian 1 were higher than in New sorghum 3.【Conclusion】 There were differences between the absorption capacities of two varieties,and the absorption capacity of Liaotian 1 was stronger than New sorghum 3.