ABSTRACT

Japanese mustard spinach with 4–5 unfolded leaves were transplanted in a nutrient film technique hydroponic system to investigate the effects of washing roots intermittently with ozonated water (OW) on plant growth. The high concentration of OW generated electrolytically was mixed in the nutrient solution tank, showed 5.8 mg.L⁻¹, and circulated through the culture beds for 1 h every week. After washing the roots with OW or tap water (TW) as a control for 1 h, Otsuka house A solution (NO₃-N: 16.8 me.L⁻¹, NH₄-N: 1.8 me.L⁻¹, P: 5.1 me.L⁻¹, K: 8.6 me.L⁻¹, Ca: 8.2 me.L⁻¹, Mg: 3.0 me.L⁻¹) at 1.2 dS.m^–1 was provided for plant cultivation in hydroponic culture systems. The OW or TW was replaced every week. The fresh and dry weights of the leaves, number of leaves, leaf length, and leaf width of plants treated with OW were significantly higher than those of the plants treated with TW at 1, 2, and 3 weeks after transplanting (WAT). The ratio of the shoot and root dry weights at 1, 2, and 3 WAT was significantly higher in plants grown in the OW flushing treatment compared with the control treatment. However, the roots dry weights were not significantly different between the OW- and TW-treated plants. Moreover, the number of coliform bacteria and aerobic plate count (APC) in the solution and plants were not significantly different between the two treatments. These results indicate that washing roots intermittently with 5.8 mg.L⁻¹ dissolved ozone concentration of OW for 1 h per week promotes aerial plant growth without physiological disorder and is not accompanied by a decrease in the number of coliform bacteria and APC in the solution and plants.

摘要

将具有 4-5 片展开叶的日本芥菜菠菜移植到营养膜技术水培系统中，以研究用臭氧水 (OW) 间歇性冲洗根部对植物生长的影响。电解产生的高浓度OW在营养液罐中混合，显示为5.8 mg.L ^-1，每周通过培养床循环1小时。用 OW 或自来水 (TW) 作为对照清洗根部 1 小时后，Otsuka house A 溶液 (NO ₃ -N: 16.8 me.L ^-1 , NH ₄ -N: 1.8 me.L ^-1 , P: 5.1 me.L ^-1，K：8.6 me.L ^-1，Ca：8.2 me.L ^-1，Mg：3.0 me.L ^-1）在1.2 dS.m^–1提供用于水培系统中的植物栽培。OW 或 TW 每周更换一次。在移栽后 1、2 和 3 周（WAT），OW 处理的植物的叶片鲜重和干重、叶数、叶长和叶宽均显着高于 TW 处理的植物。与对照处理相比，在 OW 冲洗处理中生长的植物在 1、2 和 3 WAT 下的枝条和根干重的比率显着更高。然而，OW 和 TW 处理的植物之间的根干重没有显着差异。此外，溶液和植物中的大肠菌群数量和需氧菌落数（APC）在两种处理之间没有显着差异。这些结果表明，用 5.8 mg.L 间歇性洗根^-1溶解臭氧浓度 OW 每周 1 小时可促进地上植物生长而没有生理障碍，并且不伴随溶液和植物中大肠菌群和 APC 数量的减少。