Borate cross-linked/total rhamnogalacturonan II ratio in cell walls for the biochemical diagnosis of boron deficiency in hydroponically grown pumpkin

Anal Sci. 2006 Aug;22(8):1125-7. doi: 10.2116/analsci.22.1125.


Boron (B) is an essential micronutrient for vascular plants. The function of B has been demonstrated to cross-link monomeric rhamnogalacturonan II (mRG-II) to form dimeric RG-II-borate (dRG-II-B), and thus to stabilize plant cell walls. The dRG-II-B to total RG-II ratio in the cell walls of pumpkin hydroponically grown under various low-B conditions was analyzed to evaluate its applicability to the diagnosis of plant B deficiency. The dRG-II-B ratio in cell walls ranged between approximately 0.9 in B-sufficient tissues and approximately 0.15 in severe B-deficient tissues, reflecting the B nutritional status of tissues. This result indicates that the degree of B shortage in plant tissues is very likely to be diagnosed by the dRG-II-B ratio in cell walls.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Borates / analysis
  • Borates / chemistry*
  • Boron / chemistry
  • Boron / deficiency*
  • Cell Wall / metabolism*
  • Chemistry Techniques, Analytical / methods*
  • Chromatography, High Pressure Liquid
  • Cross-Linking Reagents / pharmacology
  • Cucurbita / metabolism*
  • Pectins / chemistry*
  • Plant Proteins / chemistry
  • Plant Proteins / metabolism
  • Time Factors
  • Water / chemistry


  • Borates
  • Cross-Linking Reagents
  • Plant Proteins
  • rhamnogalacturonan II
  • Water
  • Pectins
  • Boron