摘要
为探讨外源一氧化氮(NO)对稀土元素镧(La)胁迫下植物抗氧化系统的调节机制,采用水培方法,研究了NO供体硝普钠(SNP)对200μmol·L^(-1 )La^(3+)胁迫下燕麦幼苗生长、La含量及叶片抗坏血酸-谷胱甘肽循环的影响。结果表明,施用100μmol·L^(-1 )SNP显著缓解了La^(3+)胁迫对燕麦幼苗根长、株高和植株干重的抑制,使叶片过氧化氢和丙二醛含量增幅下降;地上部La含量显著降低,并有效逆转了La^(3+)胁迫诱导的还原型抗坏血酸(AsA)、氧化型抗坏血酸(DHA)、还原型谷胱甘肽(GSH)和氧化型谷胱甘肽(GSSG)含量的升高,提高了AsA/DHA和GSH/GSSG比值及单脱氢抗坏血酸还原酶(MDHAR)、脱氢抗坏血酸还原酶(DHAR)、抗坏血酸过氧化物酶(APX)和谷胱甘肽还原酶(GR)活性。表明La胁迫下外源NO可抑制La从根系向地上部的转运,并通过提高抗坏血酸-谷胱甘肽循环相关酶活性及AsA/DHA和GSH/GSSG比值,减轻La胁迫诱导的H_2O_2对燕麦幼苗的伤害。
In order to explore the regulatory mechanism of exogenous nitric oxide(NO)on the antioxidant system of plants under rare earth elements Lanthanum(La)stress,a hydroponics experiment was conducted to investigate the effect of exogenous NO donor sodium nitroprusside(SNP)on the growth,La content and leaf ascorbate-glutathione cycle in oat seedling under 200μmol·L-1 La 3+stress.The results showed that after application of 100μmol·L-1 SNP,the root length,plant height,dry weight of root and shoot of oat seedlings under La 3+stress were significantly increased.However,the leaf contents of hydrogen peroxide and malondialdehyde were significantly decreased.Under La 3+stress,application of SNP did not significantly change the root La content,but the shoot La content was decreased significantly,and reversed the La 3+stress-induced increase of reduced ascorbic acid(AsA),dehydroascorbic acid(DHA),reduced glutathione(GSH)and oxidized glutathione(GSSG),and increased the AsA/DHA and GSH/GSSG ratios as well as the activities of monodehydroascorbate reductase(MDHAR),dehydroascorbate reductase(DHAR),ascorbate peroxidase(APX)and glutathione reductase(GR)evidently.Consequently,exogenous NO could inhibit the transport of La from root to shoot in oat seedlings under La stress,and reduce the damage of La stress to the plants by increasing the AsA-GSH cycle metabolizing enzyme activity as well as AsA/DHA and GSH/GSSG ratios.
作者
刘建新
欧晓彬
王金成
刘秀丽
李博萍
LIU Jianxin;OU Xiaobin;WANG Jincheng;LIU Xiuli;LI Boping(University Provincial Key Laboratory for Protection and Utilization of Longdong Bio-Resources in Gansu Province;College of Life Sciences and Technology,Longdong University,Qingyang,Gansu 745000,China)
出处
《麦类作物学报》
CAS
CSCD
北大核心
2018年第4期478-486,共9页
Journal of Triticeae Crops
基金
国家自然科学基金项目(31560125)
甘肃省庆阳市科技计划项目(KZ2014-19)
陇东学院博士启动基金项目(XYBY1502)
