Stimulation and Inhibition of <i>Arabidopsis</i> 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.