Identification of the silicon form in xylem sap of rice (Oryza sativa L.)

Namiki Mitani, Jian Feng Ma, Takashi Iwashita

Research output: Contribution to journalArticle

88 Citations (Scopus)

Abstract

Rice (Oryza sativa L.) is a typical silicon (Si)-accumulating plant, but the mechanism responsible for the translocation from the root to the shoot is poorly understood. In this study, the form of Si in xylem sap was identified by 29Si-nuclear magnetic resonance (NMR) spectroscopy. In rice (cv. Oochikara) cultured in a monosilicic acid solution containing 0.5 mM Si, the Si concentration in the xylem reached 6 mM within 30 min. In the 29Si-NMR spectra of the xylem sap, only one signal was observed at a chemical shift of -72.6 ppm, which is consistent with that of monosilicic acid. A 1H-NMR study of xylem sap did not show any significant difference between the wild-type rice and mutant rice defective in Si uptake, and the components of the xylem sap were not affected by the Si supply. The Si concentration in the xylem sap in vitro decreased from an initial 18 mM to 2.6 mM with time. Addition of xylem sap to a solution containing 8 mM Si did not prevent the polymerization of silicic acid. All these results indicate that Si is translocated in the form of monosilicic acid through the xylem and that the concentration of monosilicic acid is high in the xylem only transiently.

Original languageEnglish
Pages (from-to)279-283
Number of pages5
JournalPlant and Cell Physiology
Volume46
Issue number2
DOIs
Publication statusPublished - Feb 2005
Externally publishedYes

Fingerprint

Xylem
Silicon
silicon
sap
xylem
Oryza sativa
rice
nuclear magnetic resonance spectroscopy
Acids
Magnetic Resonance Spectroscopy
acids
Silicic Acid
Oryza
silicic acid
Polymerization
polymerization
mutants
shoots

Keywords

  • Nuclear magnetic resonance
  • Rice
  • Silicon
  • Xylem

ASJC Scopus subject areas

  • Plant Science
  • Physiology
  • Cell Biology

Cite this

Identification of the silicon form in xylem sap of rice (Oryza sativa L.). / Mitani, Namiki; Ma, Jian Feng; Iwashita, Takashi.

In: Plant and Cell Physiology, Vol. 46, No. 2, 02.2005, p. 279-283.

Research output: Contribution to journalArticle

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