外源褪黑素对NaCl胁迫下沙枣种子萌发和芽苗生长的影响OA

[Objective]This study aims to explore the mitigating effects of exogenous melatonin(MT)on the seed germination of and seedling growth of Elaeagnus angustifolia under NaCl stress,and to screen for the optimal MT concentration to alleviate NaCl stress.[Method]In this study,seeds of E.angustifolia from Gansu and Ningxia provenances were used as materials to analyze the impact of exogenous MT treatments(0,50,100,200,400 μmol/L)on the germination of seeds and the growth of seedlings under NaCl stress(0,50,100,150,200,250 mmol/L).[Re-sult]1)The germination and seedling growth indicators of seeds from both provenances Gansu and Ningxia signifi-cantly decreased with the increase of NaCl concentration.2)Under NaCl stress conditions,the germination effect of Gansu E.angustifolia seeds was significantly improved under 100 μmol/L MT treatment,while the growth of the seedlings was significantly enhanced under the treatment of 200 μmol/L MT.For the ningxia provenance E.angusti-folia had the best performance in seed germination and sprout growth under 100 μmol/L MT treatment.Conversely,400 μmol/L MT had an inhibitory effect on seed germination of E.angustifolia in both provenances.3)Comprehen-sive evaluation indicated that 100 and 200 μmol/L MT are the optimal concentrations to alleviate salt stress in the germination and seedling growth of E.angustifolia from Ningxia and Gansu provenances,respectively.[Conclusion]An appropriate concentration of MT can effectively mitigate the inhibitory effects of NaCl stress on the germination and seedling growth of E.angustifolia,with the effect varying due to differences in NaCl concentration and seed sources.In addition,E.angustifolia from Ningxia has a stronger salt tolerance than that from Gansu.