铝诱导玉米根系分泌异羟肟酸及对光照和铁素的响应  

Aluminum-induced hydroxamic acid secretion in maize roots and its response to light conditions and ferrum element

作　　者：莫碧霞 蒙寅恬 朱涵钰 姚校娟 杨曙[1] 黎晓峰[1] 唐新莲[1] MO Bi-xia;MENG Yin-tian;ZHU Han-yu;YAO Xiao-juan;YANG Shu;LI Xiao-feng;TANG Xin-lian(College of Agriculture,Guangxi University,Nanning,Guangxi 530004,China)

机构地区：[1]广西大学农学院,广西南宁530004

出　　处：《南方农业学报》2023年第10期2910-2917,共8页Journal of Southern Agriculture

基　　金：国家自然科学基金项目(32060722)。

摘　　要：【目的】探究铝胁迫对玉米根系异羟肟酸分泌量和玉米植株异羟肟酸含量的影响及其相关性,分析铝胁迫下玉米根系异羟肟酸分泌对环境条件(光照和铁素)的响应,为进一步探明玉米耐铝机制提供理论依据。【方法】以泰玉11号(耐铝品种)和郑单958(铝敏感品种)为试验材料,采用水培法,设0µmol/L(对照)和20µmol/L AlCl_(3)处理,分别在3、6、9、12和24 h后,测定玉米根系异羟肟酸分泌量和玉米植株体内异羟肟酸含量,分析玉米根系异羟肟酸分泌量与植株体内异羟肟酸含量的相关性;设光照条件为自然光照(14 h光照/10 h黑暗)和黑暗(24 h),Fe^(3+)浓度为0、5、10和20µmol/L,用0和10µmol/L AlCl_(3)处理24 h后,测定玉米根系异羟肟酸分泌量,分析铝胁迫下光照条件与铁素对玉米根系异羟肟酸分泌的影响。【结果】随着铝胁迫时间的延长,泰玉11号根系异羟肟酸分泌量呈增加趋势,铝胁迫9 h后,开始显著高于对照(P<0.05,下同);而在铝胁迫的各时间段,郑单958与对照均无显著差异(P>0.05,下同),且泰玉11号分泌量显著高于郑单958,泰玉11号分泌持续时间长,分泌量大,而郑单958对铝胁迫及铝胁迫时长均无明显响应。铝胁迫下玉米根系异羟肟酸分泌与玉米植株体内异羟肟酸含量密切相关,泰玉11号的分泌量与根系和叶片异羟肟酸含量呈显著或极显著(P<0.01,下同)正相关,而郑单958的分泌量与根系异羟肟酸含量无显著相关性,与叶片异羟肟酸含量呈显著或极显著负相关,铝诱导根系分泌量的增加与根系和叶片的异羟肟酸含量增加同步。黑暗条件显著提高铝胁迫下玉米根系异羟肟酸的分泌量,铝胁迫下玉米根系异羟肟酸分泌量随着铁浓度的升高整体呈增加趋势,在20µmol/L以上铁浓度时达最高值。【结论】铝诱导耐铝玉米品种泰玉11号分泌异羟肟酸,异羟肟酸的分泌可能与植株体内的异羟肟酸合成代谢相关,铝�【Objective】To explore the effect and correlation of hydroxamic acid secretion in maize roots and hy-droxamic acid content in maize plants under aluminum(Al)stress,and analyze the response of the hydroxamic acid secre-tion in maize roots under Al stress to environmental conditions[light conditions and ferrum(Fe)element],providing theo-retical basis for the mechanism of Al tolerance in maize.【Method】A hydroponic experiment was conducted,in which Taiyu 11(Al tolerant variety)and Zhengdan 958(Al sensitive variety)were experimental materials that were treated with 0µmol/L(control)and 20µmol/L AlCl_(3).After 3,6,9,12 and 24 h,the hydroxamic acid secretion in maize roots and its content in maize plants were measured to analyze the correlation between the two.The light conditions were set as natural light(14 h of light exposure/10 h of darkness)and darkness(24 h),and Fe^(3+)concentrations were 0,5,10 and 20µmol/L.After 24 h of treatment with 0 and 10µmol/L AlCl_(3),the amount of hydroxamic acid secretion in maize roots was mea-sured to analyze the effects of light conditions and Fe element on the secretion under Al stress.【Result】With the extension of Al stress time,the hydroxamic acid secretion in the root of Taiyu 11 showed an increasing trend,and after 9 h under Al stress,it began to be significantly higher than that of the control(P<0.05,the same below);whereas,in each time period under Al stress,there was no significant difference between Zhengdan 958 and the control(P>0.05,the same below)and the secretion of Taiyu 11 was significantly higher than that of Zhengdan 958.Taiyu 11 had a long secretion duration and a large amount of secretion,while Zhengdan 958 did not respond obviously to either Al stress or the length of Al stress time.Hydroxamic acid secretion in maize roots was closely related to the hydroxamic acid content in maize plants under Al stress,and the secretion of Taiyu 11 showed a significant or extremely significant positive correlation with the hy-droxamic acid content in the roots and

关 键 词：玉米 铝胁迫 异羟肟酸 合成与分泌 光照和铁 

分 类 号：S513.01[农业科学—作物学]