S. Kawabata et R. Sakiyama, EFFECTS OF MECHANICALLY RESTRICTING ENLARGEMENT OF CUCUMBER FRUITS ONWATER AND DRY-MATTER ACCUMULATION, Engei Gakkai Zasshi, 67(4), 1998, pp. 507-514
The control of soluble sugar concentration during a rapidly growing st
age was investigated in relation to water content in cucumber fruits.
To evaluate the influences of the rate of water accumulation on the co
ncentration of soluble sugars, the enlargement of the fruits was restr
icted by enclosing the fruits within acrylic sleeves to prevent mechan
ically the further accumulation of water for 3 to 4 days. The treatmen
t restricted fruit enlargement by 40% to 72% of control fruits on a fr
esh weight basis, whereas dry matter and hexose contents increased fro
m 127% to 138% and from 134% to 173%, respectively. Although sucrose c
onstitutes a small percentage of total sugars, it increased significan
tly during the treatment. The activity of acid invertase was negativel
y correlated to the concentration of sucrose, suggesting that the sign
ificant accumulation of sucrose was related to the reduced activity of
acid invertase. Whereas the concentration of soluble sugars consisten
tly increased with time, the concentration of dry matter remained cons
tant during the treatment, indicating that the accumulation of soluble
sugars was not due to excessive import of carbohydrates relative to w
ater inflow. The relationship between the concentration of soluble sug
ars and the rate of water accumulation is discussed.