Effect of high voltage discharge on germination characteristics of vetch seeds at high altitude

Abstract High-voltage electrostatic fields and low-temperature plasma technology at atmospheric pressure have an important impact on biological growth promotion. Therefore, a multi-needle-column-plate corona plasma generator is proposed in this paper. The negative corona voltammetry characteristics of multi-needle-plate electrodes and multi-needle-column-plate electrodes with different electrode spacing are investigated experimentally, and the electric field distribution of the device is simulated. The device was also applied to vetch seeds at high altitudes to investigate the effect of discharge on germination and root length. The results show that the introduction of column electrodes can effectively improve the electric field distribution of the device so that the device can provide two modes of high voltage electrostatic field and corona plasma field, and ensure the uniform treatment of seeds when the electrode spacing is 3 cm. The treatment of this device accelerates seed germination and promotes root growth, and is more effective under the combined influence of higher electric field strength, ionic wind generated by the discharge, and the active species than a single factor with a lower electric field, as well as shortening the duration of action. The high voltage electrostatic fields at −3 kV, −6 kV, and −9 kV and the corona discharge plasma fields at −12 kV, −15 kV, and −18 kV can effectively accelerate the germination of vetch seeds as well as promote the root growth under the treatment time of 10 min, 20 min, and 30 min. The optimal conditions were −9 kV for 30 min and −15 kV for 10 min, respectively.