A Coaxial Dielectric Barrier Discharge Reactor for Treatment of Winter Wheat Seeds

Abstract

Non-thermal atmospheric pressure plasmas have been recently explored for their potential usage in agricultural applications as an interesting alternative solution for a potential increase in food production with a minor impact on the ecosystem. However, the adjustment and optimization of plasma sources for agricultural applications in general is an important study that is commonly overlooked. Thus, in the present work, a dielectric barrier discharge (DBD) reactor with coaxial geometry designed for the direct treatment of seeds is presented and investigated. To ensure reproducible and homogeneous treatment results, the reactor mechanically shakes the seeds during treatment, and ambient air is admixed while the discharge runs. The DBD, operating with argon and helium, produces two different chemically active states of the system for seed modification. The temperature evolution was monitored to guarantee a safe manipulation of seeds, whereas a physiological temperature was assured by controlling the exposure time. Both treatments led to a remarkable increase in wettability and acceleration in germination. The present study showed faster germination acceleration (60% faster after 24 h) and a lower water contact angle (WCA) (82% reduction) for winter wheat seeds by using the described argon discharge (with air impurities). Furthermore, the treatment can be easily optimized by adjusting the electrical parameters.

Helium Atmospheric Pressure Plasma Jet Source Treatment of White Grapes Juice for Winemaking

“…Our plasma source mean electrical power, around 8 W, was close to the values reported by Guo, Lukic, Nishime, Pankaj and Sarangapani (2-20 W) [26,36,[92][93][94], but lower than 20-50 W as reported by Starek, Mujahid, Wang [38,95,96], or less than 50-200 W as reported by Bao, Pan, Zhao, Xiang, Laurita, Sainz-Garcia [29,40,41,43,97,98], and even far less than 300-750 W as reported by Ashtiani, Huang, Fan, Jambrak, Zhou [30,42,44,99,100]. The higher the dissipated plasma power got, the higher the possibility of thermal treatment of the sample was.…”

The Effects of Cold Atmospheric Pressure Plasma on Germination Parameters, Enzyme Activities and Induction of DNA Damage in Barley

“…However, the germination and vigor of non-infected barley grains were not significantly affected after plasma treatment. Positive effects of non-thermal plasma application on seed germination (after optimal application doses) have been observed in a great variety of plant species, including monocots,-e.g., maize [34], wheat [30,35] and rice [36]-and dicot plants-e.g., Chenopodium album [37], pea [16,38], soybean [39,40] and tomato [31]. As in our study, the negative effect of high application rates of non-thermal plasma, and in particular, the negative effect of nitrogen as a working gas, has recently been described, e.g., for peas and soybeans [38,[40][41][42].…”

Assessment of the potential of non-thermal atmospheric pressure plasma discharge and microwave energy againstTribolium castaneumandTrogoderma granarium

“…Germination of wheat grains treated with LT 90 's levels of non-thermal APPD showed that the plasma grain treatment for an appropriate time that ranged from 1.9 to 3.1 min (112.55–182.97 sec) improved the germination. Germination acceleration is further enhanced with an increase of exposition time from 11% for 3 min plasma treatment to around 40% for 30 min plasma treatment of germinated wheat grains (Nishime et al ., 2020). A similar result was found in the study of Los et al ., (2018); short plasma treatment had a minimal positive influence on the germination rate of wheat.…”