摘要
土壤酸化和铝毒害逐渐成为危害水稻生长发育和产量的重要问题,因此挖掘水稻耐铝相关基因,阐明其参与耐铝的分子机制尤为重要。前期研究利用全基因组关联分析筛选出了一个耐铝相关基因Os Al R3,通过表型和生理指标证明该基因参与水稻耐铝调控。有机酸和植物生长调节物质与铝抗性有着密切关系,但Os Al R3如何响应该过程尚未明确。本研究探讨了野生型和osalr3敲除突变体对外源有机酸(柠檬酸(CA)、草酸(OA)和苹果酸(MA))和植物生长调节物质(芸苔素内酯(BR)和生长素(IAA))的响应。研究表明,敲除突变体osalr3在铝处理下总根长显著缩短、地上部和地下部铝离子含量显著升高、根际pH和有机酸含量降低、丙二醛(MDA)、超氧阴离子(O^(2-))、过氧化氢(H_(2)O_(2))含量和超氧化物歧化酶(SOD)活性显著升高,与野生型相比表现出了对铝胁迫更敏感的表型。外施有机酸和芸苔素内酯后,突变体总根长增加,地上部和地下部铝离子含量减少,柠檬酸、草酸和苹果酸含量增加,MDA、O^(2-)、H_(2)O_(2)含量和SOD活性降低,突变体遭受铝毒害减轻。而外施生长素后虽然突变体总根长较铝处理增加,地上部铝离子含量降低,但是地下部铝离子含量显著增加,MDA、O^(2-)和H_(2)O_(2)含量均与野生型存在显著性差异。综上所述,外施有机酸(柠檬酸、草酸和苹果酸)和芸苔素内酯对Os Al R3基因起到了积极作用,而施用生长素对Os Al R3基因的功能起到了负向调节的作用。
Soil acidification and aluminum(Al)toxicity have become significant challenges affecting rice growth and yield.Therefore,it is crucial to investigate Al-tolerance-related genes and elucidate their molecular mechanisms.In a previous Genome-Wide Association Study(GWAS),the gene OsAlR3,associated with Al tolerance,was identified.OsAlR3 was shown to regulate Al tolerance in rice through phenotypic and physiological mechanisms.While organic acids and plant growth regulators are known to be involved in Al resistance,the specific role of OsAlR3 in these processes remains unclear.This study examined the responses of wild-type(WT)and osalr3 knockout mutants to exogenous organic acids(citric acid(CA),oxalic acid(OA),and malic acid(MA))and plant growth regulators(brassinolide(BR)and auxin(IAA)).Compared to WT,the osalr3 mutant exhibited significantly reduced total root length,inter-root pH,and organic acid content,while above-ground and below-ground Al3+content,malondialdehyde(MDA),superoxide anion(O2܋),hydrogen peroxide(H_(2)O_(2))content,and superoxide dismutase(SOD)activity were significantly increased under Al stress.The osalr3 mutant showed heightened sensitivity to Al stress compared to WT.Exogenous application of organic acids and BR increased total root length,CA,OA,and MA content,and decreased above-ground and below-ground Al3+content,MDA,O2܋,H_(2)O_(2) content,and SOD activity,thereby reducing the Al toxicity in osalr3 mutants.In contrast,although auxin application increased total root length and reduced above-ground Al3+content in the mutant,it significantly increased below-ground Al3+content,along with MDA,O2܋,and H_(2)O_(2) levels,which were markedly different from those of WT.In summary,exogenous application of organic acids(CA,OA,and MA)and BR positively influenced OsAlR3 function,while IAA application negatively regulated OsAlR3 function under Al stress.
作者
苏畅
满福原
王镜博
冯晶
姜思旭
赵明辉
SU Chang;MAN Fu-Yuan;WANG Jing-Bo;FENG Jing;JIANG Si-Xu;ZHAO Ming-Hui(Rice Research Institute,Shenyang Agricultural University/Collaborative Innovation Center for Genetic Improvement and High Quality and Efficiency Production of Northeast Japonica Rice in China,Shenyang 110866,Liaoning,China)
出处
《作物学报》
北大核心
2025年第3期676-686,共11页
Acta Agronomica Sinica
基金
财政部和农业农村部国家现代农业产业技术体系建设专项(CARS-01-09)
辽宁省科技重大专项(2022JH1/10200003)
兴辽英才项目(XLYC2008025)资助。
作者简介
第一作者:苏畅,E-mail:2022200074@stu.syau.edu.cn;通信作者:赵明辉,E-mail:mhzhao@syau.edu.cn。
