Comparison of Wall Polymers among Three Genetically Closely Related Strawberry Cultivars with Different Fruit Firmness

Three local varieties of related strawberries, were examined to find the relationship between fruit firmness and cell wall matrix. Firmness loss between the white to full ripe stage in firm variety, 'Maehyang' was lower and contained higher amount of ethanol insoluble solids (EIS) at full ripe stage. Firmness difference was not found at full ripe stage between soft varieties, 'Akihime' and 'Seohyang', even 'Akihime' had a significantly higher amount of ethanol insoluble solids than 'Seolhyang'. The water soluble pectin of 'Maehyang' occupied about 54.1% of total pectins whereas it was 63.7% and 62.5% in 'Akihime 'and 'Seolhyang', respectively. Difference in cellulose contents was not found between varieties and fruit developmental stages. The level of total neutral sugars of EIS was much lower in 'Seolhyang' compared to the other varieties. Arabinose showed a decreasing trend regardless of varieties along with the advance of ripening. There was an increase of galactose contents in 'Seolhyang' unlike in the other varieties. Gel chromatography elution profiles of wall polysaccharide showed no clear relationships between fruit firmness and depolymerization.