钼和汞胁迫对辽宁碱蓬二型种子幼苗生长及生理特性的影响OA

This study investigated the effects of different Mo and Hg concentrations on the growth and physiological metabolism of seedlings from the dimorphic seeds of the halophyte Suaeda liaotungensis and explored their tolerance to heavy metal stress.The research provides a theoretical basis for the development and utilization of S.liaotungensis in remediating heavy metal-contaminated saline-alkali soils.The root length,shoot length,and root and shoot tolerance indices in seedlings of dimorphic seeds of S.liaotungensis decreased with increasing Mo2+and Hg2+concentrations.Seedlings from black and brown seeds exhibited greater tolerance to Hg and Mo stress,respectively.Under Mo and Hg stress,physiological indices such as malondialdehyde(MDA),catalase(CAT),soluble sugars,and proline displayed a significant increasing trend(P<0.05),whereas peroxidase(POD)showed a significant decreasing trend(P<0.05).In addition,under Mo and Hg stress,the root and shoot lengths of seedlings from dimorphic seeds were positively correlated with POD,but negatively correlated with MDA,CAT,proline,and soluble sugars.This indicates that the seedlings of dimorphic seeds adapt to Mo and Hg stress by accumulating large amounts of proline and soluble sugars,and elevating CAT activity.The differences in the tolerance of the seedlings dimorphic seeds of S.liaotungensis to heavy metal stress have driven the evolution of more adaptive ecological strategies.This provides an important theoretical basis for studying its tolerance mechanism to heavy metal stress,and confirms the value of this species in remediating heavy metal-contaminated saline-alkali soils.