Yu Wang1, Xingliang Duan1, Sheng Xu2, Ren Wang2, Zhaozeng Ouyang3, Wenbiao Shen4. 1. College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China. 2. Institute of Botany Jiangsu Province and Chinese Academy of Sciences, Nanjing 210014, China. 3. Shuigu Environmental Protection Technological Company Ltd, Shanghai 200437, China. 4. College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China wbshenh@njau.edu.cn.
Abstract
BACKGROUND AND AIMS: Boron is essential for plant growth but hazardous when present in excess. As the antioxidant properties of hydrogen gas (H2) were recently described in plants, oxidative stress induced by excess boron was investigated along with other biological responses during rice (Oryza sativa) seed germination to study the beneficial role of H2 METHODS: Rice seeds were pretreated with exogenous H2 Using physiological, pharmacological and molecular approaches, the production of endogenous H2, growth status, reactive oxygen species (ROS) balance and relative gene expression in rice were measured under boron stress to investigate mechanisms of H2-mediated boron toxicity tolerance. KEY RESULTS: In our test, boron-inhibited seed germination and seedling growth, and endogenous H2 production, were obviously blocked by exogenously applying H2 The re-establishment of ROS balance was confirmed by reduced lipid peroxidation and ROS accumulation. Meanwhile, activities of catalase (CAT) and peroxidase (POX) were increased. Suppression of pectin methylesterase (PME) activity and downregulation of PME transcripts by H2 were consistent with the alleviation of root growth inhibition caused by boron. Water status was improved as well. This result was confirmed by the upregulation of genes encoding specific aquaporins (AQPs), the maintenance of low osmotic potential and high content of soluble sugar. Increased transcription of representative AQP genes (PIP2;7 in particular) and BOR2 along with decreased BOR1 mRNA may contribute to lowering boron accumulation. CONCLUSIONS: Hydrogen provides boron toxicity tolerance mainly by improving root elongation, water status and ROS balance.
BACKGROUND AND AIMS: Boron is essential for plant growth but hazardous when present in excess. As the antioxidant properties of hydrogen gas (H2) were recently described in plants, oxidative stress induced by excess boron was investigated along with other biological responses during rice (Oryza sativa) seed germination to study the beneficial role of H2 METHODS:Rice seeds were pretreated with exogenous H2 Using physiological, pharmacological and molecular approaches, the production of endogenous H2, growth status, reactive oxygen species (ROS) balance and relative gene expression in rice were measured under boron stress to investigate mechanisms of H2-mediated boron toxicity tolerance. KEY RESULTS: In our test, boron-inhibited seed germination and seedling growth, and endogenous H2 production, were obviously blocked by exogenously applying H2 The re-establishment of ROS balance was confirmed by reduced lipid peroxidation and ROS accumulation. Meanwhile, activities of catalase (CAT) and peroxidase (POX) were increased. Suppression of pectin methylesterase (PME) activity and downregulation of PME transcripts by H2 were consistent with the alleviation of root growth inhibition caused by boron. Water status was improved as well. This result was confirmed by the upregulation of genes encoding specific aquaporins (AQPs), the maintenance of low osmotic potential and high content of soluble sugar. Increased transcription of representative AQP genes (PIP2;7 in particular) and BOR2 along with decreased BOR1 mRNA may contribute to lowering boron accumulation. CONCLUSIONS:Hydrogen provides boron toxicity tolerance mainly by improving root elongation, water status and ROS balance.
Authors: Kundan Kumar; Kareem A Mosa; Sudesh Chhikara; Craig Musante; Jason C White; Om Parkash Dhankher Journal: Planta Date: 2013-10-20 Impact factor: 4.116
Authors: B M Buchholz; D J Kaczorowski; R Sugimoto; R Yang; Y Wang; T R Billiar; K R McCurry; A J Bauer; A Nakao Journal: Am J Transplant Date: 2008-08-22 Impact factor: 8.086