腐殖酸钠对镉胁迫下冬小麦种子萌发及根系生长的影响

目的]研究腐殖酸钠(HA-Na)对镉胁迫下冬小麦种子萌发及根系生长的影响。方法]以鲁麦22号为试验材料,研究不同浓度Cd~(2+)溶液处理对冬小麦种子萌发和根系生长的影响,以及不同浓度HA-Na溶液对Cd~(2+)胁迫下冬小麦种子萌发和根系生长的影响。结果]Cd~(2+)胁迫使冬小麦种子萌发和根系生长均受到抑制,发芽率、发芽指数、活力指数、幼苗根长及芽长均降低。低浓度的HA-Na提高了Cd~(2+)胁迫下冬小麦种子发芽势、发芽率、发芽指数、活力指数以及幼苗根长、芽长,部分缓解了Cd~(2+)胁迫对冬小麦种子萌发和幼苗生长的抑制作用。其中以50μmol/L HA-Na溶液处理的缓解效果最好,但随着HA-Na浓度的增大,其对Cd~(2+)胁迫的缓解效应逐渐减弱,当HA-Na浓度达200μmol/L时,会明显加剧Cd~(2+)胁迫的毒害作用。结论]该研究为被重金属污染的农田土壤治理和改良提供了理论依据。

Effect of Sodium Humate on Winter Wheat Seed Germination and Root Growth under Cadmium Stress

Objective] To study the effect of sodium humate (HA-Na) on winter wheat seed germination and root growth under cadmium stress.Method] With Lumai 22 as material,we analyzed effects of different concentrations of Cd2 + solution on winter wheat seed germination and root growth,then explored effects of different concentrations of HA-Na solution on seed germination and root growth under cadmium stress.Result] Winter wheat seed germination and root growth were inhibited by Cd2+ stress,germination index,vigor index,root length and bud length were decreased.Low concentrations of HA-Na improved winter wheat seed germination rate,germination index and vigor index,also improved root length,bud length under Cd2+ stress,and partial relieved seed germination and seedling growth under Cd2+ stress.The ameliorative effect of 50 μmol/L HA-Na was best among them.But with the increasing of concentration of HA-Na,the ameliorative effect of Cd2 + stress weakened gradually.It would significantly increase the toxic effects of cadmium stress while HA-Na concentration reached 200 μmol/L.Conclusion] The study provides the theory basis for farmland soil management and improvement that has been polluted with heavy metals.