EDDS对Cd胁迫下三叶鬼针草幼苗NO产生的影响  

Effects of EDDS on NO production in the seedlings of Bidens pilosa L.under Cd stress

作　　者：丁浚刚 陈银萍[1] 杨波[1] 师小平 颉海帆 DING Jungang;CHEN Yinping;YANG Bo;SHI Xiaoping;XIE Haifan(School of Environmental and Municipal Engineering,Lanzhou Jiaotong University,Lanzhou 730070)

机构地区：[1]兰州交通大学环境与市政工程学院,兰州730070

出　　处：《生态科学》2020年第4期19-25,共7页Ecological Science

基　　金：国家自然科学基金项目(31560161;31260089;31640012)。

摘　　要：通过室内盆栽试验,研究了40 mg·kg-1 Cd(CdCl2·2.5 H2O)胁迫下,不同浓度乙二胺二琥珀酸(EDDS)(0、0.5、1.5、2.5、5.0 mmol·L-1)单施及EDDS与一氧化氮(NO)供体硝普钠(SNP)(0、0.25、0.5、1.0 mmol·L-1)联合施加对三叶鬼针草(Bidens pilosa L.)幼苗应激信号分子NO产生量和一氧化氮合酶(NOS)活性的影响。结果表明:单施EDDS,植株不同部位NO生成量随EDDS浓度的升高呈增加趋势,5.0 mmol·L-1时达到最大;0.5 mmol·L-1的EDDS可增强根、叶中NOS活性。在探究NO产生较多和NOS活性增强显著的EDDS处理浓度与SNP联合施加的研究中发现,随SNP浓度的升高,根中NO生成量先升高后降低,茎和叶中持续升高;适宜浓度的SNP可进一步增强植株体内NOS活性。EDDS诱导NO的生成会被硝酸还原酶(NR)抑制剂(NaN3)和NOS抑制剂(L-NAME)抑制,对EDDS处理下NOS活性影响较小。NO清除剂(c-PTIO)能有效清除部分NO,增强根和叶中NOS活性。因此,在Cd胁迫下,适宜浓度的EDDS单施及与SNP联合施加都会增加三叶鬼针草幼苗体内NO产生量。An indoor pot experiment was conducted to study the effects of EDDS(0,0.5,1.5,2.5,5.0 mmol.L-1)and EDDS combined with nitric oxide(NO)donor sodium nitroprusside(SNP)(0,0.25,0.5,1.0 mmol.L-1)on stress signal molecule(NO)and nitric oxide synthase(NOS)activity production of Bidens pilosa L.seedlings under 40 mg·kg-1 Cd(CdCl2.2.5 H2O)stress.The results showed that NO production in different parts of Bidens pilosa seedlings increased with the increase of EDDS concentration,and reached the maximum at 5.0 mmol·L-1;0.5 mmol·L-1 EDDS enhanced nitric oxide synthase(NOS)activity in roots and leaves.Selecting EDDS treatment concentration with more NO production and significant increase in NOS activity to combined with SNP to treat Bidens pilosa seedlings showed that NO production in roots increased first and then decreased,but increased continuously in stems and leaves with the increase of SNP concentration.The NOS activity in the plant could be further enhanced by appropriate concentration of SNP.The NO induced by EDDS was inhibited by nitrate reductase(NR)inhibitor(NaN3)and NOS inhibitor(L-NAME),and NaN3 and L-NAME had little effect on NOS activity.The NO scavenger(c-PTIO)effectively removed some of the NO and enhanced NOS activity in roots and leaves.Therefore,under the stress of Cd,the NO production in Bidens pilosa L.seedlings could be increased by single application of EDDS and combined application of SNP with suitable concentration.

关 键 词：EDDS NO 三叶鬼针草 CD胁迫 NOS 

分 类 号：Q494[生物学—生理学]