高鹽分養液中磷濃度對番茄果實產量、品質及植株生長之影響

Effect of Phosphorus Level in High Sodium Nutrient Solution on Fruit Yield, Quality and Plant

本試驗目的在探討高鹽分養液中含不同磷濃度對番茄果實產量、品質和植株生長之影響，以供生產高品質番茄之參考。番茄品種‘桃麗’以NFT系統栽培，對照組養液EC值2.5 dS•m^(-1)含有1800μM磷，處理組為養液添加NaCl至EC值6.0 dS•m^(-1)，並分別含有14.4、72、360、1,800μM磷等。5種處理植株之1到8果房果實總產量分別為2,181、1,496、1,665、2,114及1,668 g／plant，可販售果實產量分別為2,033、1,339、1,474、1,971及1,497 g／plant，在6.0dS•m^(-1)NaCl養液中含有360μM磷處理之植株有較高產量。不同處理第8果房果實可溶性固形物含量分別為6.2、6.1、6.0及6.3°Brix，滴定酸度分別為0.82、0.76、0.74和0.72%，均較對照組的5.0°Brix和0.57%為高，果實抗壓力（compression force）亦相對較高。不同處理組果汁之NO3-和Ca2+離子含量均較對照組低；但K+和Na+離子則較對照組高；處理間以EC6.0 dS•m^(-1)養液含有1,800μM磷處理的果汁PO4-離子含量顯著較對照組高，其他處理則較對照組低。植株生育以EC6.0 dS•m(-1)養液中含有72和14.4μM磷處理之葉片面積和乾物重顯著較對照組低，葉面積比（specific leaf area）則以14.4、72和1,800μM磷處理顯著較對照組低。顯示高NaCl的養液栽培，可提高果實品質，但為改善產量降低及植株生長受抑制之缺失，依本試驗結果推算，養液中添加265μM磷濃度效果最佳。 Hydroponics is applied in tomato production widely, and fruit quality can be improved by adding sodium chloride (NaCl) into nutrient solution. However, high salinity results in inhibition of plant growth and decline of fruit yield. The effect of phosphorus level in high sodium nutrient solution on fruit yield, quality and growth of plants was investigated in this experiment to solve this problem. Tomato plants of cv. Taoli were grown with nutrient film technology (NFT). The EC (electrical conductivity) of basic nutrient solution was2.5 dS•m^(-1), containing 1,800μM phosphate. NaCl was added to the basic nutrient solutions up to EC 6.0 dS•m^(-1) first, and then various phosphorus levels containing 14.4, 72, 360, 1,800μM phosphate were augmented as the treatments. The results showed that fruit yield from the 1(superscript st) to 8(superscript th) truss of check and treatments were 2,181, 1,496, 1,665, 2,114, 1,668 g/plant, respectively. The TSS (total soluble solid) of fruits at the 8(superscript th) truss of plants which grown under treatments and check were 6.2, 6.1, 6.0, 6.3, and 5.0 °Brix, and the TA (titrate acids) were 0.82, 0.76, 0.74, 0.72, and 0.57%, respectively. The results also indicated that the leaf area and dry weight of plants grown with 14.4 and 72μM phosphorus were lower than those of check. The SLA (specific leaf area) of 14.4, 72, and 1,800μM phosphorus treatments were lower than check as well. It is suggested that phosphorus level between 200-400μM of nutrient solution is reasonable, and the predicted optimal phosphorus level based on fruit yield is 265μM, while tomato was grown with high sodium nutrient solution.