植物生态学报 ›› 2011, Vol. 35 ›› Issue (9): 981-989.DOI: 10.3724/SP.J.1258.2011.00981

• 研究论文 • 上一篇    

NO和H2O2诱导大豆根尖和边缘细胞耐铝反应的 作用

王芳妹1, 蔡妙珍2,*(), 张淑娜1, 王宁1, 李华飞1,3, 胡雪娜2, 虞舒航2   

  1. 1浙江师范大学化学与生命科学学院, 浙江金华 321004
    2浙江师范大学地理与环境科学学院, 浙江金华 321004
    3正始中学, 浙江宁波 315100
  • 收稿日期:2011-03-09 接受日期:2011-07-02 出版日期:2011-03-09 发布日期:2011-09-01
  • 通讯作者: 蔡妙珍
  • 作者简介:*(E-mail: mzcai@zjnu.cn)

Effects of nitric oxide and hydrogen peroxide on induction of a defense response in the root tips and root border cells of soybean plants to Al toxicity

WANG Fang-Mei1, CAI Miao-Zhen2,*(), ZHANG Shu-Na1, WANG Ning1, LI Hua-Fei1,3, HU Xue-Na2, YU Shu-Hang2   

  1. 1College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, Zhejiang 321004, China
    2College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, Zhejiang 321004, China
    3Zhengshi Middle School, Ningbo, Zhejiang 315100, China
  • Received:2011-03-09 Accepted:2011-07-02 Online:2011-03-09 Published:2011-09-01
  • Contact: CAI Miao-Zhen

摘要:

NO和H2O2是参与植物抗非生物胁迫反应的重要信号分子, 为了确定NO和H2O2在大豆(Glycine max)根尖和根边缘细胞(root border cells, RBCs)耐铝反应中的作用及其相互关系, 以‘浙春3号’大豆为材料, 研究了铝毒胁迫下大豆根尖内源NO和H2O2的变化, 以及外源NO和H2O2诱导大豆根尖和RBCs的耐铝反应。结果表明, 50 μmol·L-1 Al处理48 h显著抑制大豆根的伸长, 提高Al在根尖的积累, 同时显著增加根尖内源NO和H2O2含量。施加0.25 mmol·L-1外源NO供体亚硝基铁氰化钠(Na2[Fe(CN)5NO]·2H2O, sodium nitroprusside, SNP)和0.1 mmol·L-1H2O2, 能有效地缓解Al对大豆根伸长的抑制、根尖Al积累和RBCs的死亡, 该缓解作用可以被0.05 mmol·L-1NO清除剂2-(4-羧基苯)-4,4,5,5-四甲基咪唑-1-氧-3-氧化物,钾盐 (C14H16N2O4·K, carboxy-PTIO, cPTIO)和150 U·mL-1H2O2清除酶(catalase, CAT)逆转。并且外源NO能够显著促进根尖H2O2的积累, 而外源H2O2对根尖NO的含量无显著影响。这表明NO和H2O2是诱导大豆根尖及RBCs耐铝反应的两种信号分子, NO可能通过调控H2O2的形成, 进而诱导大豆根尖及RBCs的耐铝反应。

关键词: 铝毒, H2O2, NO, 根尖, 根边缘细胞, 大豆

Abstract:

Aims Nitric oxide (NO) and hydrogen peroxide (H2O2) function as signaling molecules in plants. A role for NO and H2O2 in the regulation of many abiotic stress responses, including drought, salt, heat, heavy metal and Al stresses, has been proposed. Our objective was to investigate (a) the Al-dependent accumulation of endogenous NO and H2O2 in root tips and (b) the role of exogenous NO and H2O2 in alleviating Al toxicity in root tips and root border cells (RBCs).
Methods Seedlings of soybean (Glycine max) ‘Zhechun No. 3’ were divided into two groups for hydroponic and aeroponic cultured experiments. In order to investigate the response of endogenous NO and H2O2 in root tips to 50 μmol·L-1Al, we determined root elongation, Al content in root apexes, endogenous NO and H2O2 content and their location in hydroponic cultured experiments. In the aeroponic culture experiments, seedlings were pretreated with exogenous NO and H2O2, then RBCs viability as well as the indicators in hydroponic cultured experiments were tested to clarify the role of exogenous NO and H2O2 on alleviating Al toxicity in root tips and RBCs.
Important findings Al inhibited root elongation, increased Al content in root apexes and induced endogenous NO and H2O2 accumulation with the hydroponic culture. Results of the aeroponic experiments demonstrated that both 0.25 mmol·L-1NO donor sodium nitroprusside (SNP) and 0.1 mmol·L-1 H2O2 alleviated the inhibitory effect of Al, decreased Al accumulation in root tips and enhanced RBCs viability. The 0.05 mmol·L-1 NO scavenger cPTIO (carboxy-PTIO) and 150 U·mL-1 H2O2 scavenger CAT (catalase) reversed the alleviating effect. Furthermore, the results indicated that exogenous NO promoted the accumulation of H2O2 in root apexes, while exogenous H2O2 did not significantly affect NO content in root apexes. All of these results suggested that the rise of NO and H2O2 were in accordance with defense response in root apexes and RBCs to Al toxicity in soybean, and the increase of NO may regulate the H2O2 production to protect soybean from Al toxicity.

Key words: Al toxicity, hydrogen peroxide, nitric oxide, root apex, root border cells, soybean