オウトウ垣根仕立ての収量に及ぼす栽植密度と結果枝構成の影響(栽培管理・作型)  [in Japanese] Effects of Planting Density and Bearing-Branch Composition on the Yield of Sweet Cherry Grown by Hedge-row Training  [in Japanese]

オウトウ垣根仕立ての収量向上を目的に,結果枝の構成を花束状短果枝と短果枝が多くなるよう改善することと,列間隔を縮めて栽植密度を高める二つの方法について比較した.花束状短果枝と短果枝の形成を目的として,側枝上に,従来の新梢基部5cmを利用した短果枝に加えて,長さ30cmの枝を30cm間隔で配置した.これにより,花束状短果枝は減少したが,従来の短い結果枝を含めた短果枝の合計数は増加し,収量は557kg・10a^<-1>から1,024kg・10a^<-1>に増えた.しかし,この方法では樹冠内の日射量の低下の影響により果実品質が低下した.一方,3mの列間隔を2mないし1.5mに縮めて栽植密度を高める方法では,果実品質の低下は認められなかった.3mの列間隔では収量が588kg・10a^<-1>であったのに対して,2mでは881kg・10a^<-1>に,1.5mでは1,101kg・10a^<-1>に増収した.このことから,オウトウ垣根仕立てにおいて列間隔を縮めて増収を図ることが,果実品質を低下させず,収量を向上させる方法として有効であるとことが明かとなった.

To improve the yield of sweet cherries (Prunus avium L.) grown by hedge-row training, the following two methods were compared : increased numbers of spurs and bouquet spurs to improve the spur composition and narrowed row intervals to increase planting density. To develop spurs and bouquet spurs, 30cm long branches were positioned at 30cm intervals on lateral branches in addition to the conventional spur development from 5cm current shoots. Although this measure decreased the number of bouquet spurs, it increased the total number of spurs including the conventional short spurs to improve the yield to 1, 024kg・10a^<-1> from 557kg・10a^<-1> using conventional hedge-row training. However, this method decreased solar radiation in the tree crowns thereby lowering fruit quality. In contrast, increasing planting density from 3-m intervals to 2- or 1.5-m intervals did not affect fruit quality. Moreover, in contrast to a yield of 588kg・10a^<-1> when row intervals were 3m, the row intervals narrowed to 2m and 1.5m improved the yield to 881kg・10a^<-1> and 1, 101kg・10a^<-1>, respectively. The above results show that decreasing row intervals is an effective method for increasing the yield of sweet cherries grown by hedge-row training without lowering fruit quality.