Cd胁迫黄土中施用污泥对小麦生长的影响及吸收Cd的效应

Effect of application of sewage sludge on the growth of wheat and absorption of Cd under Cd stress in loess

以黄土和小麦为材料,采用盆栽试验研究了Cd胁迫下施用污泥对小麦生长及富集迁移Cd的特征变化.结果表明:黄土中低水平的Cd胁迫可促进小麦的生长,高水平的Cd胁迫抑制小麦的生长;土壤中Cd临界质量分数在5 mg/kg附近.小麦各部位的Cd质量分数与土壤中的Cd质量分数呈显著正相关关系,且根系最大,茎叶次之,籽粒最小,小麦各部位对Cd的富集能力随着Cd胁迫水平的升高而先增加后减小,籽粒和茎叶的迁移能力变异性较大.

A pot experiment was conducted out for loess and wheat to study the characteristics of growth of wheat with sewage sludge application and the migration and accumulation of Cd in different levels of Cd stress.The results showed a phenomenon that high concentrations of Cd promoted the growth of wheat and low concentrations of Cd suppressed it in loess.The critical point of concentrations of Cd was around 5 mg/kg.The concentrations of Cd in different parts of wheat and soil showed a significant positive correlation.The concentrations order of Cd in different parts of wheat was：root stem seed.With the increasing level of Cd,the ability of accumulation of Cd in different parts of wheat first increased then decreased.The ability of migration of Cd in stem and seed was variable.