培養液への塩類の添加が水耕栽培トマトの糖度と果実重量に及ぼす影響(土壌管理・施肥・潅水)  [in Japanese] Effects of Salt Application on Total Soluble Solids and Fruit Weight of Tomato Grown in Hydroponics(Soil Management, Fertilization & Irrigation)  [in Japanese]

トマトの毛管式水耕栽培において,標準培養液に人工海水塩を添加して,塩類処理が果実の糖度と重量に及ぼす影響を調査した.3段摘心栽培では,培養液のECが高く推移した区ほど糖度は高く,糖度と果実重量には負の相関が認められた。標準液に2000ppmの塩類を添加した培養液で栽培を始め,第3花房開花期から標準液補給に変えて培養液のECを低下させた区では,目標に近いBrix8.5〜9.7の糖度が確保でき,全期間塩類を添加処理した区に比べて,果実重量の低下もやや抑えることができた.8段摘心栽培では,培養液の窒素濃度を高め,さらに塩類を加えてEC6 dS・m^<-1>で栽培した区で第1果房からほぼ目標糖度に達し,塩類のみでECを高めた処理区に比べて,上段果房での果実重量の低下も避けることができた.

Effects of salt application on total soluble solids (TSS) and fruit weight were investigated in tomato plants grown in hydroponics. In plants pinched above the third truss, there was a high negative correlation between TSS content and fruit weight. When electrical conductivity (EC) was reduced after anthesis of the third truss, TSS content was maintained around 9% without severe reduction of fruit weight. In plants pinched above the 8 th truss, TSS content was about 9% in all 8 trusses and the fruit weight of the upper trusses was not reduced by increasing the nitrogen concentration of the solution and maintaining EC 6 dS ・m^<-1> throughout the cultivation.