Changes of Sugar Kind and Its Content in the Fruit of Watermelon during Its Development and after Harvest.

To be of high quality the flesh of watermelon must be red in color, of crisp texture, and sweet.Especially sweetness of fruit, which is outcome of sugar content, is most important.Considering this, investigation was made as to changes of sugar kind and its content in the fruit of watermelon during its development and after harvest with the results as follows : 1) Major sugars detected in the fruit were fructose, glucose and sucrose.2) Fructose and glucose were found at a very early stage of fruit development and became maximum from 30 to 40 days after pollination, and then decreased.3) Sucrose came into existence for the first time 30 days after pollination, and thereafter increased in quantity.In each case sugar content was high near the seeds.4) Fructose and glucose decreased rapidly after harvest, but sucrose, on the contrary, increased after harvest.The reasons for these phenomena are discussed.