中山間傾斜地におけるブルーベリーのコンテナ養液促成栽培の実用化(栽培管理・作型)  [in Japanese] Forcing Culture of Blueberry Grown in a Container Using a Hydroponics System Suitable for Use in Hilly and Mountainous Areas(Crop Production & Cropping Type)  [in Japanese]

中山間傾斜地の気象特性を活かし,本研究室でこれまでに開発した傾斜ハウスや傾斜地対応型養液供給システムなどを有効に利用できる作目として,ブルーベリーの促成栽培を検討した.ブルーベリーは,移動できるようにコンテナに定植して養液栽培を行った.定植より10〜17か月後,各品種の枯死率を調査したところ,'Earliblue'が最も高く,養液栽培に不適であると判断された.促成栽培では,徳島県三加茂町の中山間傾斜地の露地圃場(標高約300m)で低温に遭遇させた後,2月初旬に隣接の加温傾斜ハウスに搬入した.促成栽培の開花は,多くの品種で2月下旬から始まり,促成を行なっていない所内(香川県善通寺市)に比べると35日以上も早かった.促成栽培の収穫は,多くの品種で4月下旬〜5月上旬に始まり,所内の6月上旬に比べて35日程度早かった.促成栽培では,初期収量は'Patriot'および'Weymouth'で多かったが,収穫期間中の収量は'Northland'および'Sharpblue'で多かった.'Sunshineblue'は,収穫のピークが遅く,促成栽培には不向きであった.促成栽培の収穫果実の出荷単価は1kg当り平均3,389円であり,他の時期に比べて高かった.本実験より,ブルーベリーの促成栽培は,四国をはじめとする中山間傾斜地の施設利用の作型として有望であると考えられる.

We developed a sloped greenhouse and a hydroponics system suitable for use on sloping land. To use the greenhouse and the system effectively during the winter season, we investigated forcing culture of blueberry. We transplanted 15 cultivars of blueberry plants in containers filled with a peat-moss and supplied nutrient solution by the hydroponics system. Ten to 17 months after transplanting to the container, we investigated the death rate among plants of each cultivar. The death rate of plants was the highest in 'Earliblue'. We considered that 'Earliblue' was unsuitable for the hydroponics system. In forcing culture, the plants experienced a term of cold temperature when placed outdoors in hilly and mountainous area (about 300m above sea level) in Mikamo, Tokushima until 3 February, 2004. After 3 February, the plants were brought into a heated greenhouse near the field. Flowering of plants in forcing culture started at the end of February, which was 35-40 days earlier than flowering of plants under standard culture in Zentsuji, Kagawa. Harvesting from plants in forcing culture started at the end of April, which was about 35 days earlier than that from plants in standard culture. In forcing culture, at the beginning of harvesting term, fruit yields from 'Patriot' and 'Weymouth' were higher than those from other cultivar. However, for the experimental term, the yields from 'Northland' and 'Sharpblue' were higher than those from other cultivars. 'Sunshineblue' was unsuitable for forcing culture because of the late harvest period. The average price of shipped fruits from forcing culture was higher (\3,389 kg^<-1>) than that during other seasons. We supposed that forcing culture of blueberry using the greenhouse and the hydroponics system was promising culture method in hilly and mountainous areas.