《植物生理学报》 2010, 46(7): 707-713

外源NO 对缺镁胁迫下玉米幼苗生长和离子平衡的影响

熊英杰¹, 赵立群², 钟韬韬¹, 安长廷¹, 梁荣¹, 孙宝腾^1,*

1 南昌大学生命科学与食品工程学院, 南昌330031; 2 河北师范大学生命科学学院, 石家庄050016

通信作者：孙宝腾；E-mail: sbt72@163.com；Tel: 0791-8331501

摘　要：

研究了在缺镁胁迫下, 外源 NO 对缺镁玉米幼苗生长、根系活力和离子含量的影响。结果表明, 缺镁胁迫使玉米幼 苗株高、根长和干鲜重下降, 根系活力降低, N 元素在地上部和根部分配失调, 新叶和老叶中 Mg2+、Cu2+、Fe3+、Mn2+ 等 离子含量下降, Ca2+、K+、Zn2+ 等离子含量上升。根中 Mg2+ 离子含量下降, Ca2+、K+、Zn2+、Cu2+、Fe3+、Mn2+ 等离子含 量上升。用100 μmol•L-1 一氧化氮供体硝普钠(SNP)处理后, 玉米幼苗株高、根长、干重和鲜重均提高, 根系活力增强, 改善 了 N 代谢, 新叶中 Ca2+、K+ 和 Zn2+ 等离子含量下降, Mg2+、Cu2+、Fe3+ 和 Mn2+ 等离子含量提高, 老叶中 Mg2+、Ca2+、K+ 和 Zn2+ 等离子含量下降, Cu2+、Fe3+ 和 Mn2+ 等离子含量提高, 根中 Mg2+、Ca2+、K+、Cu2+、Zn2+、Fe3+ 和 Mn2+ 离子含量均下 降。实验结果表明, NO 保护玉米幼苗免受缺镁胁迫的影响。

关键词：玉米; 缺镁胁迫; 一氧化氮; 离子平衡

收稿：2010-04-15   修定：2010-05-13

资助：江西省教育厅项目(赣教技字[2007] 39 号)和教育部博士点新教师基金(20091303120005)。

Effects of Exogenous Nitric Oxide on the Growth and Ion Homeostasis of Maize (Zea mays L.) Seedlings under Magnesium Deficient Stress

XIONG Ying-Jie¹, ZHAO Li-Qun², ZHONG Tao-Tao¹, AN Chang-Ting¹, LIANG Rong¹, SUN Bao-Teng^1,*

¹College of Life Sciences and Food Engineering, Nanchang University, Nanchang 330031, China; ²School of Life Sciences, Hebei Normal University, Shijiazhuang 050016, China

Corresponding author: SUN Bao-Teng; E-mail: sbt72@163.com; Tel: 0791-8331501

Abstract:

Effects of exogenous nitric oxide (NO) on the growth, root activity and some inorganic ions changes of maize seedlings under magenesium deficient stress were investigated. The results showed that the shoot and root length, fresh and dry weight of maize seedlings were reduced under magnesium deficient stress. The root activity was reduced under magnesium deficiency, either. The distribution of nitrogen in shoot and root was interfered under magnesium deficiency stress. The contents of inorganic ions such as Mg²⁺, Cu²⁺, Fe³⁺ and Mn²⁺in younger and older leaves of maize subjected to magnesium deficiency were decreased while those of Ca²⁺, K⁺and Zn²⁺ increased. Magnesium content in root of maize seedlings was decreased under Mg deficient condition, but the contents of Ca²⁺, K⁺, Zn²⁺, Cu²⁺, Fe³⁺ and Mn²⁺ were increased. In comparison with magnesium deficient stress, the shoot length, root length, fresh weigth and dry weight of maize seedlings treated with 100 μmol·L^-1sodium nitroprusside (SNP), an nitric oxide donor, was increased. The root activity was increased due to SNP treatment, either. The distribution and partition of N was rationalized in shoot and root. The contents of Mg²⁺, Cu²⁺, Fe³⁺ and Mn²⁺ in younger leaves and those of Cu²⁺, Fe³⁺ and Mn²⁺ in older leaves were increased due to SNP treatment. Whereas the contents of Ca²⁺, K⁺ and Zn²⁺ in younger leaves and Mg²⁺, Ca²⁺, K⁺ and Zn²⁺ in older leaves were decreased under SNP treatment condition. Contents of all of the ions were decreased in roots of magnesium deficient maize seedlings due to SNP treatment. The results obtained showed that NO protected maize seedlings from magnesium deficiency stress.

Key words: maize; magnesium deficiency stress; nitric oxide; ion homeostasis