叶面喷施Fe2O3NPs对娃娃菜NaCl胁迫的缓解效应OA北大核心CSTPCD

[Objective]The aim is to explore the alleviation effect of nano-iron oxide(Fe2O3NPs)on salt stress of Mini Chinese Cabbage.[Method]With'Huangfei'Mini Chinese Cabbage as the test material and ultrapure water as the control,different concentrations of Fe2O3NPs(0,25,50,100,200,400,500 mg/L)were sprayed on the leaves under 150 mmol/L NaCl stress.[Result]NaCl stress inhibited plant growth by affecting Mini Chinese Cabbage root growth,leaf cell membrane lipid peroxidation,antioxidant enzyme activities,and the AsA-GSH cycle.Spraying different concentrations of Fe2O3NPs promoted root growth,increased leaf glutathione reductase(GR),dehydroascorbate reductase(DHAR),ascorbate peroxidase(APX)activities,antioxidant GSH content and GSH/GSSG ratio,and reduced hydrogen peroxide(H2O2),superoxide(H2O2),superoxide anion(O2-),malondialdehyde(MDA),proline(Pro)content and relative electrical conductivity(REC).The spraying effectively mitigated the inhibitory effect of NaCl stress on the growth of Mini Chinese Cabbage seedlings.Fe2O3NPs at 500 mg/L significantly increased total root length,root volume,root tip number and root surface area of Mini Chinese Cabbage plants under salt stress by 55.66%,56.33%,68.49%and 57.61%,respectively;it significantly reduced the H2O2,O2-,MDA and Pro contents in leaves by 48.77%,42.50%,23.68%,and 47.53%,respectively;it significantly enhanced GR,DHAR,and APX activities,and increased GSH content and GSH/GSSG ratio by 16.39%,18.66%,56.64%,and 35.41%and 60.26%,respectively.[Conclusion]150 mmol/L NaCl stress had a significant negative effect on the growth of Mini Chinese Cabbage seedlings,and exogenous sprays of Fe2O3NPs at different concentrations(25-500 mg/L)were able to effectively alleviate the inhibitory effect of NaCl stress;the alleviating effect of 500 mg/L Fe2O3NPs was optimal under the experimental conditions.