CHANGES OF CELL WALL POLYSACCHARIDES RELATED TO WATERCORE IN ‘HOSUI’ PEAR FRUIT (P. PYRIFOLIA) GROWN IN ALLUVIAL AND VOLCANIC SOILS

This study was carried out to determine the difference in watercore occurrence in fruit grown on volcanic and alluvial soil during 2004 and 2005. ‘Hosui’ pear fruits were collected from two commercial orchards with different soil properties.
Additionally, calcium solution (500 mg L^-1 CaO) was applied to determine the effects on watercore occurrence in fruits grown on volcanic soil.
Cell wall polysaccharides were investigated for their suitability as markers for watercore occurrence.
Alcohol insoluble solid (AIS) content decreased during fruit growth in both years.
The decrease of AIS content was delayed to 75 days after full bloom (DAFB) in 2004 rather than 60 DAFB in 2005. The amount of water-soluble polyuronides (WSP) and Na₂CO₃ soluble polyuronides (ASP) in fruit increased continuously during fruit growth.
Fruits grown in alluvial soil showed lower WSP content and higher ASP content than those in volcanic soil.
Hemicellulose content was higher in fruits grown in alluvial soil than in volcanic soil during 2004 and 2005. Also, it was increased a little by one calcium spray on volcanic soil.
Consequently, we suggest that the weak accumulation of cell wall components could be one cause of watercore occurrence in pear fruit.

XXVII International Horticultural Congress – IHC2006: International Symposium on Enhancing Economic and Environmental Sustainability of Fruit Production in a Global Economy

S.H. Lee, H. Gemma, S. Sugaya, Y. Sekozawa, W.S. Kim

alkali soluble pectin, calcium, hemicellulose, water soluble pectin

https://doi.org/10.17660/ActaHortic.2008.772.55