| Project/Area Number |
09556004
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 展開研究 |
|---|
| Research Field |
作物学
|
|---|
| Research Institution | Hokkaido University |
|---|
Principal Investigator |
IWAMA Kazuto Faculty of Agriculture, Hokkaido University, Associate Professor, 農学部, 助教授 (70144219)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
SATO Hajime Hokkaido University of Education, Professor, 教育学部, 教授 (20091530)
TAKAYANAGI Shigeru Hokkaido University of Education, Professor, 教育学部, 教授 (50013529)
YAMAGUCHI Junichi Faculty of Agriculture, Hokkaido University, Associate Professor, 農学部, 助教授 (80001478)
|
|---|
| Project Period (FY) |
1997 – 1998
|
| Project Status |
Completed (Fiscal Year 1998)
|
| Budget Amount *help |
¥10,800,000 (Direct Cost: ¥10,800,000)
Fiscal Year 1998: ¥4,100,000 (Direct Cost: ¥4,100,000)
Fiscal Year 1997: ¥6,700,000 (Direct Cost: ¥6,700,000)
|
|---|
| Keywords | Electrical potential / Water content of plant / Plant pH / Ag-AgCl electrode / Water stress / Rice / Potato / Kidney bean / 銀塩化銀電極 |
|---|
| Research Abstract |
An experimental apparatus on a trial basis designed for measuring electrical potential on a plant surface was made to estimate water and nutrient stress of crops under field conditions (Exp. 1). and tested with kidney bean (Exp. 2), potato (Exp. 3) and rice (Exp. 4).
Exp.l. The developed system for measurements of activation voltage generating in the plants has pre-amplifiers, power source, connecting box to supply the power to many amplifiers, and calibrator. Activation voltage of the plants was measured with the high impedance amplifier designed by voltage follower type.
Exp.2. In the first, copper tube inserted into soil was confirmed to be reliable as a standard electrode. Secondly, an electrical component of the surface potential was examined by measurement of electrical potential at xylem of different parts in the stem. To investigate uncertain repeatability on a daily change of the surface potential, last experiment was conducted by measurement of the surface potential in the dark room.
Exp.3. The surface voltage generally started to decrease after sunrise, maintained low value during mid-day, and increased during the night. The difference between night and mid-day was about 50-100 mV.However, the difference was also found between the stem nodes of one plant and also of different plants.
Exp.4. The surface potentials differed among positions in rice leaf-sheath, but they were additive. The gradient of the surface potential was not, however, linear with the vertical positions. Continuous change of the potentials was often interrupted at a certain position and the interrupted positions moved time to time throughout a day. Therefore, a small difference (possibly less than a few mm) in measurement positions will be a major cause of the potential variation among individual plants.
|
