Abstract
To elucidate the mechanism of carbohydrate accumulation by two developing pumpkins (kabocha), 'Miyako' (Cucurbita maxima Duch.) and 'Hayato' (Cucurbita moschata Duch.), which differ in taste and textures when cooked, their carbohydrate compositions were compared. The changes of total sugar content during fruit growth differed between 'Miyako' and 'Hayato'. The total sugar content of 'Miyako' fruit increased gradually after 30 days from flowering (DAF) while that of 'Hyato' fruit increased steadily during fruit growth. 'Miyako' fruit accumulated starch faster than did fruits of 'Hayato'. A high negative correlation exists between starch and moisture contents in both cultivars, indicating that the moisture content decreased as starch content increased. Raffinose oligosaccharides, monosaccharides and sucrose were the principal soluble sugars accumulated by the fruit. Raffinose oligosaccharide content was higher in 'Hayato' than in 'Miyako'.
