Effect of Different Ultrafine Bubble Content in Nutrient Solution on Lettuce (Lactuca sativa L. cv. Frillice): Growth, Superoxide Radical Accumulation, and Total Antioxidant Capacity

Previous studies have reported that ultrafine bubbles (UFBs) can promote plant growth. However, the optimum application of UFBs has not been sufficiently clarified yet. In this study, we investigated UFB content index for lettuce cultivation. Content (CI) was defined as product pass numbers (Pn) and dilution ratio (D) taken to be indicative density; where Pn number times water passed through generator. treatment comprised three different Pn: 10 passes (P1), 25 (P2), 100 (P3). Six treatments were conducted each in six D as: control, 10%, 30%, 50%, 75%, 100%. The results confirmed there an appropriate level CI accelerate growth a hydroponic solution, is, 7.5―30 18.75―30 nursery cultivation stages, respectively. significantly smaller on 100. addition, DPPH NBT tests measure total antioxidant capacity (TAC) superoxide radical lettuce. TAC accumulation influenced by index.