Study on Effect of Transient Electromagnetic Field on the Growth of Radish

—Assessing the Effect of the Pulse Width of Transient Electromagnetic Field—

Abstract

This paper presents an effect of transient-electromagnetic fields (or pulsed electromagnetic fields) on the growth of the radish. In our experiment, two kinds of transient electromagnetic fields by spark discharges were applied to seeds and seedlings of the radish. When generating spark discharges, the pulse widths of discharge current (800 A) were set to 3 µs and 15 µs, respectively. Based on measured discharge currents, we also evaluated the energy level of electromagnetic fields by using an electric dipole model. The analytical results quantitively confirmed that a waveform with a short pulse-width (3 µs) can generate high frequency energy component although the total energy of a waveform with a wide pulse-width (15 µs) is greater. Then, regarding the growth rate of the radish, we found that the weight of enlarge roots (or tuberous root) for the pulse width of 3 µs became greater than the others (control [no application] and the pulse width of 15 µs) by around 23-38%. In addition, the t-test-based statistical assessment confirmed that there were statistically significant differences in the mean value between the control and 3 µs groups at the significance level of 5%.