山西农业大学学报（自然科学版）2025，Vol.45Issue(4)：67-77,11.DOI:10.13842/j.cnki.issn1671-8151.202504025
油菜素内酯调控谷子抗旱性的生理机制研究
Physiological mechanisms underlying brassinosteroid-mediated drought tolerance in foxtail millet
摘要
Abstract
[Objective]Drought stress during the booting stage severely constrains yield formation in foxtail millet.This study aimed to investigate the effects of exogenous brassinosteroid(BR)application on key physiological and biochemical processes to elucidate its role in enhancing drought tolerance,providing a theoretical basis for BR-based drought resistance improvement.[Method]Using the foxtail millet variety'Jingu 21'as experimental material,a pot experiment was conducted with three treat-ments:well-watered control(CK),drought stress with water spray(DS),and drought stress with 0.1 μmol/L BR application(DBR).The effects of exogenous BR on yield parameters,photosynthetic characteristics(SPAD,Rubisco activity,net photo-synthetic rate(Pn),stomatal conductance(Gs)),chlorophyll fluorescence,osmolytes(soluble sugars,proline),antioxidant enzymes(superoxide dismutase(SOD),ascorbate peroxidase(APX),glutathione reductase(GR)),oxidative markers(hy-drogen peroxide(H2O2),malondialdehyde(MDA)),nitrogen metabolism enzymes(nitrate reductase(NR),glutamine syn-thetase(GS)),and endogenous hormones(endogenous gibberellin(GA3),abscisic acid(ABA))in millet under drought stress were investigated.[Results]Compared to DS,DBR treatment significantly improved multiple physiological indicators:photosynthetic parameters increased by 8.33%～26.15%with significant improvements in chlorophyll fluorescence parame-ters.Leaf soluble sugar and free proline content increased by 13.15%and 12.14%,respectively;antioxidant enzymes activi-ties(SOD,APX,and GR)increased by 14.62%～31.63%,while oxidative stress markers(H2O2and MDA)reduced nota-bly.DBR also significantly enhanced NR and GS activities,increased GA3 content by 14.98%and reduced ABA by 12.86%.Ultimately,DBR significantly boosted yield by 16.10%per plant with improved panicle traits.[Conclusion]During the booting stage,exogenous brassinosteroid application can effectively alleviate the negative effects of drought stress on millet by optimiz-ing photosynthetic performance,enhancing osmotic adjustment,activating the antioxidant defense system,promoting nitrogen metabolism,and regulating endogenous hormone balance through multiple physiological pathways,thereby facilitating yield for-mation in millet.关键词
谷子/干旱/孕穗期/油菜素内酯/抗氧化系统/调控激素Key words
Foxtail millet/Drought/Booting stage/Brassinolide/Antioxidant system/Hormone regulation分类
农业科技引用本文复制引用
杜杰,夏路阳,冯宇,夏清,王文霞..油菜素内酯调控谷子抗旱性的生理机制研究[J].山西农业大学学报（自然科学版）,2025,45(4):67-77,11.基金项目
山西省青年科学基金(202203021222320) （202203021222320）
山西省高等学校科技创新项目(2023L377) （2023L377）
吕梁市高层次科技人才计划项目(2023RC20 （）
2024RC30) （）
