2020 Volume 34 Issue 1 Pages 194-204
The test method for evaluating the promotion effect of Ultrafine Bubble (UFB) on barley seed germination was published as an ISO standard in July 2019. There should be a minimum number concentration of UFB that can provoke early seed germination, but it is still unclear. Hence, we conducted a germination examination by applying UFB water containing different number concentrations. The results showed that the promotion of germination is observed statistically with UFB water whose number concentration is in the range of 10 to the 8th power/ml. The difference in the number concentration of UFB was also supported by ESR analysis. After the application of ultrasonic sound of 43 kHz for 30 s, UFB water containing UFB of 6.03 x 108 particles/mL showed the larger signal intensity of reactive oxygen species which was composed more of hydroxyl radicals than that of 1.26 x 108 particles/mL. This fact indicated the difference in the number concentration of UFB without any effect of foreign matter included in UFB water.
