2002 Volume 71 Issue 2 Pages 155-163
Fruit growth and increases in the flesh cell number and size from blossom to maturity were investigated on early-ripening 'Saotome', mid-season 'Akatsuki', late-season 'Yuzora' and wild 'Ohatsumomo' peach cultivars. The duration of each growth stage differed with the cultivar, especially Stage II ; three stages were short in 'Saotome'. It was confirmed that the fruit growth after the cessation of cell division was dependent on cell enlargement. Mesocarp cells did not grow uniformly during Stage III ; rather, the radial cell length near the stone was greater than those of outer portions. Flesh cells continued to divide for four to five weeks after full bloom, and increased in size thereafter. The time when cell division ceased showed varietal differences ; 'Saotome', in which cell division ceased early, had a small number of flesh cells and produced small fruit. The wild peach 'Ohatsumomo', whose cells divided more slowly than the commercial cultivars had the fewest and the smallest cells, resulting in very small fruit.