1995 Fiscal Year Final Research Report Summary
Sugar concentration of fruit as affected by accumulation and hydrolysis of polysaccharides and water inflow.
| Project/Area Number |
05454053
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
園芸・造園学
|
|---|
| Research Institution | The University of Tokyo |
|---|
Principal Investigator |
SAKIYAMA Ryozo The University of Tokyo, Faculty of Agriculture, Professor., 農学部, 教授 (70011955)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
KAWABATA Saneyuki The University of Tokyo, Faculty of Agriculture, Assistant Professor, 農学部, 助手 (10234113)
|
|---|
| Project Period (FY) |
1993 – 1995
|
| Keywords | Fruit / Starch hydrolysis / Sugars / Water / Concentration / Kiwifruit |
|---|
| Research Abstract |
This study was a basic research aiming to control the sugar concentration which has a great infuluence on the fruit quality. For sugars in fruit, the concentration has been an object of many researches, however, less studies have not paid attention the fact that concentration is a relative value of soluble constituents against water.
In this study, fruit of starch-storing kiwifruit was choosen and a relationship between hydrolisys of sugars and water inflow was determined.
Starch accumulation occurred at an earlier stage of fruit growth and showed a maximum even during the early part of the third growth period when fruit growth was rapid. During this period sugar concentration was lower. Over the middle and later parts of that period when fruit ceased to grow, sucrose concentration increased rapidly, probably caused by starch hydrolysis. This is conrasted to the fact reported for plant tissues where the increase in sugar concentration induces lowering of water potential, in turn causes water inflow, and as a result disappeared. This suggests water inflow was blocked between stem and fruit. The possible causes of the blockage could be (1) the decrease in water conductivity through conductive tissues of fruit stems, (2) the decrease in semi-perpeability of cell membranes, and/or (3) the decrease in cell wall extensibility of fruit tissues. The third one will be removed because the turgor pressue did not show a remarkable rise.
Concludingly, in fruit of kiwifruit both of starch hydrolysis and the decrease in water inflow occurred concuirently so that they contributed to the increase in sugar concentration.
|
