バラの排液循環型ロックウール栽培におけるNH_4-N, FeおよびMnの添加が収量および培養液組成に及ぼす影響(土壤管理・施肥・灌水)  [in Japanese] Effects of NH_4-N, Fe and Mn Supplement on the Yield of Cut Roses and the Composition of Recirculating Nutrient Solution in a Closed Rockwool Cultivation System(Soil Management, Fertilization & Irrigation)  [in Japanese]

バラのロックウール栽培において, 培養液を循環利用するために, 砂と活性炭による緩速ろ過後の排液の水での希釈およびNH_4-N, FeおよびMnの補充の有無が閉鎖型での培養液循環栽培における収量, 品質および培養液濃度に及ぼす影響について'ローテローゼ'を用いて検討した.総切り花本数は, 砂と活性炭で緩速ろ過後の培養液を水で2.5倍に希釈後に循環利用した場合, 愛知花研バラ処方冬用の養分組成による成分補充の有無に関わらず, かけ流し栽培と同等の35本・株^<-1>(約241,000本・10a^<-1>)であった.切り花品質も成分補充の有無に関わらず, かけ流し栽培とほぼ同等であった.かけ流し栽培における栽培施設10a当たりの1年間の全窒素施与量は290.3kgであり, そのうち廃棄量は135.9kgであった.緩速ろ過後の培養液を水で希釈後に成分補充を行い循環利用した場合の全窒素施与量は151.8kg, 成分補充せず循環利用した場合の全施与量は110.5kgであり, かけ流し栽培に比べて著しく減少した.さらに, 培養液を循環利用した場合の窒素およびリン酸等の廃棄量は0kgであった.培養液中の無機成分濃度は, 排液を砂と活性炭で緩速ろ過すると低下した.とくに, PO_4-P, Mn, FeおよびSO_4-S濃度は著しく低下した.培養液を循環利用した場合には, 培養液中のNaおよびCl濃度が著しく上昇したが, 植物体への障害は観察されなかった.バラのロックウール栽培において, 排液を緩速ろ過装置でろ過し, 水で2.5倍に希釈する場合には成分補充する必要はないことが示された.

To research the cyclic use of the drainage solution in a closed system of rockwool cultivation of cut roses, we examined the effects of diluting the drainage solution with water, both with and without additions of NH_4-N, Fe and Mn nutrient components following the slow sand and active charcoal filtration of the drainage solution. The yields of the cut flower stems were almost the same as those in the conventional cultivation, at 35per plant, when the drainage solution was recirculated, and whether or not we added nutrient components. The cut flower stem quality was almost the same as those in the conventional cultivation, in each drainage cycle. Under the conventional cultivation system, the total nitrogen quantity applied per 1,000m^2 cultural facilities for 1year was 290.3kg, and the quantity for disposal was 135.9kg. Under the closed system, using the added nutrient components, the total nitrogen quantity was 151.8kg, and with no added nutrients components, the total for disposal was only 110.5kg. In addition, under the closed systems, there was no nitrogen and phosphoric acid to dispose of in each drainage cycle. PO_4-P, Mn, Fe and SO_4-S concentrations in the drainage solution were lowered, after the drainage solution was slowly filtered. Na and Cl concentrations in the solution rose remarkably when the filtered drainage solution was circulated. However, no symptoms of mineral excess or deficiency were observed in the rose plants. In a closed system of rock wool rose cultivation, it was shown that there was no necessity to supplement the nutrient components, when the drainage solution was diluted by 2.5times after slow filtration process.