Project/Area Number |
03454044
|
Research Category |
Grant-in-Aid for General Scientific Research (B)
|
Allocation Type | Single-year Grants |
Research Field |
園芸・造園学
|
Research Institution | Hirosaki University |
Principal Investigator |
KIKUCHI Takuro Hirosaki University, Faculty of Agriculture, Professor, 農学部, 教授 (90003425)
|
Co-Investigator(Kenkyū-buntansha) |
SHIOZAKI Yunosuke Hirosaki University, Faculty of Agriculture, Associate Professor, 農学部・附属農場, 助教授 (50003471)
ARAKAWA Osamu Hirosaki University, Faculty of Agriculture, Associate Professor, 農学部, 助教授 (70184265)
ASADA Takenori Hirosaki University, Faculty of Agriculture, Associate Professor, 農学部, 助教授 (10003518)
|
Project Period (FY) |
1991 – 1993
|
Project Status |
Completed (Fiscal Year 1993)
|
Budget Amount *help |
¥3,900,000 (Direct Cost: ¥3,900,000)
Fiscal Year 1993: ¥300,000 (Direct Cost: ¥300,000)
Fiscal Year 1992: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 1991: ¥2,900,000 (Direct Cost: ¥2,900,000)
|
Keywords | Tree form / Tree canopy / Pruning / Open center / Central leader / Apple / 受光率 / 品質 / 樹冠 / 受光指数 |
Research Abstract |
Field studies were made on the canopy structure and fruit productivity of the two orchard systems ; the conventional open-center trees and the "HU System" central leader trees developed in our experimental farm for medium-density orchards on Malus prunifolia rootstock. The main conclusions drawn from the results are as follows. 1. The highest yield level per ha of markettable fruits is about the same in the mature stage between the open-center orchards and the central leader orchards. 2. more training and pruning skills and appropiate tree vigor control are required to increase fruit yield per ha by means of increasing orchard LAIs(leaf area index), particularly in the LAI range over somewhere about 2. 3. Within the canopies of the central leader trees as well the open-center trees, markettable fruits are well distributed into the within-tree portions receiving relative light intensities as low as 20% or lower. It can be ascribed to the careful and detailed pruning and fruit thinning. 4. In the open-center trees the characteristic positioning of the secondary scaffolds branches and lateral branches developed on them facilitates the restriction of tree height, the maintenance of the vigor of lateral and fruiting branches, and their frequent renewals. 5. In the central leader trees grown on vigorous rootstocks, the within-tree light conditions favorable for fruit production can be maintained by restricting the branches arising from the central leader by far shorter than the bottom limbs which are developed rather big. 6. The depth of the main cropping zone is about 1.7m on the average in the open-center trees and the central leader trees as well. In this connection, the central leader trees should not be expanded over 2m from the trunk even at the bottom of the canopy.
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