[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Cd2+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Cd2+胁迫下冬小麦种子萌发和根系生长的影响.[结果] Cd2+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Cd2+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Cd2胁迫对冬小麦种子萌发和幼苗生长的抑制作用.其中以50 μmol/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Cd2+胁迫的缓解效应逐渐减弱,当HA-Na浓度达200 μmol/L时,会明显加剧Cd2+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.%[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.
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