Studies on the Translocation of Photosynthates in Satsuma Mandarin

With decreasing moisture supply, the 14C activity of the ethanol soluble fraction in the fruit increased in comparison with that of the ethanol insoluble fraction. Sugars may be major constituents of the former fraction, and polysacharides those of the latter. It appears that the suppression of polysacharide synthesis may result in more sugar accumulation in the juice. Although the translocation of photosynthates was depressed by withholding water, sugar content per fruit was rather higher than that of the controls. Thus, it was tentatively supposed that the hydrolysis of cell wall constituents may also occur leading to the high sugar content in the fruit under moisture stressed conditions.