STUDY ON WATERCORE OCCURRENCE IN HOSUI JAPANESE PEAR

Fruits of ‘Hosui’ pear, in which watercore as a physiological disorder sometimes occurs when grown on alluvial soils, but not on volcanic soils, were investigated in terms of histological change and cell wall polysaccharide degradation with maturation.
A strange shaped cell, plugged by a putatively sugar-like substance, was observed in the fruit of volcanic soil-grown trees in mid-July under light microscopy.
The amount of alcohol-insoluble solids (AIS) from the fruit grown on volcanic soil was lower than that from alluvial soil-grown fruit in both mid-July and late-August, as 37.5-40.1mg/g and 7.8-9.3 mg/g, respectively.
Cell wall polysaccharide, notably the fractions referring to hemicellulose and cellulose, in fruit of volcanic soil-grown trees showed a similar tendency to AIS during maturation, and can be considered the predominant cell wall decomposition products.
No differences in the Ca contents in leaf and fruit were found between fruit from either soil even though the volcanic soils contained high Ca level.
Why the strange shaped cell was generated per se is still unknown, but this phenomenon can apparently be involved in watercore occurrence.

VIII International Symposium on Pear

H. Gemma, S. Oomori, S. Sugaya, S-A. Peng, S. Iwahori

AIS, alluvial soil, Ca element, cell shape, cell wall, firmness, polysaccharide, volcanic soil

https://doi.org/10.17660/ActaHortic.2002.596.146