The effect on the germination and seedling growth of radish (Raphanus sativus) seeds were examined employing a dielectric barrier discharge (DBD) at atmospheric pressure and room temperature for various treatment time. DBD plasma using argon gas of flow rate 2 l m−1 was employed in this study. Radish seeds were treated with DBD plasma for 1–5 min, respectively. Germination characteristics, seedling growth parameters, the contact angle of the seed coat, water uptake capacity, mass loss, the temperature of the seeds, chlorophyll, and carotenoid contents of the seedlings were measured before and after the DBD plasma treatments. Plasma treatment of radish seeds significantly increased germination-related characters, including germination percentage, fresh and dry weight, vigor index, and total carotenoids contents. However, the cumulative production rate was found to be decreased. Results from the experiment indicate an acceleration in the water uptake of the radish seeds and make the seed surface hydrophilic by plasma treatment. Scanning electron microscopy analysis showed that etching effects on the seed coat occurred after the argon plasma treatments, which affected the wettability of the radish seed. The experimental findings showed that seeds being treated by DBD plasma for 2 and 3 min had a positive effect on the germination and seedling growth of radish.

Seed germination is a complicated physiological process that starts with the seed absorbing water and concludes with the radicle emerging. The kinetics and amount of water uptake by seeds are known to be influenced by both seed surface properties and the surrounding environment. As a result, altering seed surface features are linked to seed medium and is a valuable strategy for controlling seed germination. In the agricultural field, non-thermal plasma surface activation of seeds is currently being investigated as an efficient pre-sowing treatment for modifying seed germination. The impact of non-thermal plasma (NTP) on the germination and seedling growth of carrot seeds at room temperature and atmospheric pressure for varied treatment times was investigated in this study. Seed's germination properties and growth parameters were examined for both control and NTP treated seeds. Germination-related parameters such as germination percentage, vigor index, and chlorophyll content were all improved by NTP treatment. However, no significant changes were seen in the carotenoid content. Similarly, the in-vitro radical scavenging activities, total phenol, and total flavonoid contents in the seedlings were altered by NTP treatment. Our results indicate that NTP treatment has a favorable effect on carrots germination and seedling development.

The present study reports the generation of plasma-activated water (PAW) using dielectric barrier discharge (DBD), its physicochemical properties, and its potential impact on the seed germination and seedling growth of soybean. The results revealed significant changes in physical parameters, such as pH, total dissolved solids, total suspended solids, turbidity, conductivity, dissolved oxygen, and chemical parameters, such as calcium, chromium, sodium, manganese, nitrate, nitrites, phosphorus, and sulfur and biological parameter such as E. coli in water after plasma treatment. The concentration of dissolved oxygen, conductivity, nitrate, nitrite, and sulfur was increased with an increase in water treatment time, and the amounts of the other analyzed parameters decreased with the increase in water treatment time. The effects of untreated water and plasma-activated water treated for 20 minutes on soybean germination and growth were studied. The germination rate was found to be higher with plasma-treated water. Shoot lengths, seedlings length, vigor index, and germination rates were increased as compared to those germinated by normal water irrigation. The seedlings irrigated with PAW responded to the abundance of nitrogen by producing intensely green leaves because of their increased chlorophyll a as compared to seedlings irrigated with normal water. However, the content of chlorophyll b and carotenoids was found to decrease in the case of seedlings irrigated with PAW. Based on this report, we conclude that PAW could be used to substantially enhance seed germination and seedling growth.

In this study, an atmospheric alternating-current gliding arc device using line frequency (50 Hz) has been designed for the generation of various reactive species in different working gases. Electrical characteristics of the generated discharge are investigated by oscilloscope while the optical characteristics are analyzed using optical emission spectroscopy. The role of different working gases (oxygen, argon and air) on discharge voltages and power consumption per cycle in the discharge are calculated and compared. Electron density and electron temperature of the discharge are estimated by electrical and optical method respectively. The production of reactive species in the discharge is affirmed by optical emission spectroscopy. The outcomes of the results confirm that the GAD can generate non-equilibrium plasma having reactive nitrogen and oxygen species (RONS) which are essential for plasma chemistry applications.

The low surface energy of HDPE limits its industrial uses as it is not suitable for printing and adhesion. The main aim of this work is to improve the wetting properties of high-density polyethylene (HDPE) using air dielectric barrier discharge (DBD) operating at the line frequency (50 Hz). The estimation of electron temperature and electron density has been done by electrical and optical methods. The surface roughness of the control and plasma treated polymer film is analysed by contact angle (CA) measurement, surface energy measurement and scanning electron microscope (SEM) analysis. The contact angle was found to be suppressed from 93.180±2.00 to 63.750±0.880 after 10s of plasma treatment which implied that the surface property had changed to a hydrophilic state caused by an increase in the surface roughness.