Stimulation and Inhibition of Arabidopsis Seed Germination with Repetitive Barrier Discharges Produced by Polarity‐Reversed Voltage Pulses

Abstract

SUMMARY This paper presents an experimental study of control of the germination of Arabidopsis seed with a barrier discharge produced by polarity‐reversed voltage pulses. 100 ns‐width polarity‐reversed pulses were applied to the seeds between plane electrodes covered by glass barriers. The electrode configuration allowed barrier discharge propagation along the seed surface at a relatively low voltage. After the discharge treatment, the seeds were incubated for 2 or 3 days to measure the germination rate. The relationships between the cumulative input energy density into the plasma and the germination rate were investigated. The germination rate was significantly reduced at 20 J/cm3. However, it increased at cumulative energy densities up to 50 J/cm3 and then decreased again on further energy input. These results suggest a superposition of two effects, stimulation and inhibition, of the discharge treatment on the germination of Arabidopsis seed. The results of Evans Blue dyeing of the discharge‐exposed seeds indicate that necrosis of the seed coat is caused by the discharge treatment.

Effects of plasma activated water on wheat: Germination, growth parameters, photosynthetic pigments, soluble protein content, and antioxidant enzymes activity

“…When using the plasma, it is very important to know and optimize the plasma exposure/activation time. Short exposures may induce weak effects, while long exposures may result in inhibition and can negatively affect the seed germination and development of the plants …”

Pulsed power applications for agriculture and food processing

“…The germination rate and seedling growth rate increased with the DC electric field exposure. They also confirmed that the of stem length of the mature plant was affected by the exposing DC voltage polarity (Kadowaki and Kurisaka 2013). Huang et al reported that germination of tomato seeds was induced by exposure to AC electric field of 4-12 kV/cm in strength and also by exposure to magnetic field of 3-100 G with an irradiation period from 15 to 60 s. The germination of the seed increased 1.1-2.8 times compared with that of the control (without exposure).…”

Entering the plasma agriculture field: An attempt to standardize protocols for plasma treatment of seeds

“…This also provides the opportunity to perform a visual check for plasma uniformity and reliable ignition, and to check that all seeds have the same plasma exposure to reduce variation. [21] If the plasma setup uses a gas flow, flow flushing is recommended for a sufficient time to establish the nominal gas conditions [9,23,85] before beginning the plasma treatment of the seeds and to avoid the accumulation of RONS between replicates. Additionally, flow flushing also helps to reduce the effect of humidity on DBD electrodes (see Section 3.2).…”

“…DBDs generally work in the kilohertz range, although experiments can operate from 50 Hz [13,19,31,39,45,63,104,110,116] to 30 kHz [47] and up to nanopulse frequencies. [17,[21][22][23]91] Plasma jets have been operated from 500 Hz in AC bipolar square waveform, [101] to 58 kHz. [70,73] The continuous wave AC mode is preferentially implemented rather than the pulsed mode.…”

“…It is often measured directly, using current and voltage probes, by time-integrating the current-voltage product. [21,41,41,[47][48][49][50][51]55,56,58,63,104,119,129,130] However, because a precise time-dependent measurement of the fast current pulses in DBDs is generally difficult, the dissipated discharge power is more conveniently calculated from the DBD voltage and the cycleaveraged DBD current using the charge measured on a series capacitor: The enclosed area of the charge-voltage diagram, known as a Lissajous figure whose locus repeats for each cycle, [131] gives the energy per AC period. Examples of Lissajous figure calculations can be found in References [11,15,19,19,27,45,51,53,62,64,116,131].…”