一氧化氮对铅胁迫下杂花苜蓿种子萌发及幼苗生理特性的影响

摘要

以杂花苜蓿阿尔冈金(Medicago varia cv.ALgonquin)为试验材料，采用沙培方法，研究了外源一氧化氮(NO)供体硝普钠(SNP)对 Pb2+处理下杂花苜蓿种子萌发及幼苗生理特性的影响。结果表明，与对照比，用 SNP(100μmol/L)、低 Pb2+浓度(250 mg/L)和 SNP 与低 Pb2+浓度组合(100μmol/L SNP +250 mg/L)处理均增加了杂花苜蓿种子的发芽势、发芽率、胚芽胚根长，提高了幼苗脯氨酸、可溶性糖及可溶性蛋白质的含量，增强了根系活力，降低了 MDA 含量。高 Pb2+浓度(500 mg/L)处理不利于杂花苜蓿种子萌发和幼苗生长，且100μmol/L SNP 不能缓解高铅胁迫对种子萌发及幼苗生长的抑制作用。%Medicago varia cv.Algonquin was used to study the effects of nitric oxide donor SNP on seed germination and seedlings physiological characteristics under lead stress by sand culture.The results showed that the treatments with SNP of 100 μmol/L concentration,Pb of 250 mg/L concentration,and Pb of 250 mg/L and SNP of 100 μmol/L concentrations resulted in the improvement of germination potential,germination rate, root length,shoot length and root activity,and increasing of proline,soluble sugar and soluble protein contents, but the MDA content was decreased.High concentration Pb solution (500 mg/L)inhibited seedling growth and SNP (100 μmol/L)could not reduce the damage in this case.