Plasma-Activated Water Modulates Root Hair Cell Density via Root Developmental Genes in Arabidopsis thaliana L.

Dong Hyeun Ka,Joo Young Park,Young Koung Lee,Seong Bong Kim,Soon Ju Park,Ryza Aditya Priatama,In Ah Lee

doi:10.3390/app11052240

Abstract

Low-temperature atmospheric pressure plasma technology has been used in agriculture and plant science by direct and indirect treatment of bio-samples. However, the cellular and molecular mechanisms affected by plasma-activated water (PAW) are largely unexplored. In this study, PAW generated from a surface dielectric barrier discharge (SDBD) device was used for plant development. Physicochemical analysis was performed to confirm the PAW properties that correlated with the plasma treatment time. Arabidopsis thaliana L. was utilized to study the effect of the PAW treatment in the early developmental stage. The plasma-activated water samples are denoted as PAW5 time in minutes (min), PAW7 min, PAW12 min, PAW19 min and PAW40 min with the plasma treatment time. Seedlings grown in the PAW5, PAW7 and PAW12 had increased root lengths while the root lengths were decreased in the PAW19 and PAW40. In the cellular level observation, the PAW treatment specifically increased the root hair numbers per unit of the root but suppressed the root hair length in the PAW, indicating that PAW mainly modulates the root hair cell density in the root. Furthermore, we found that the root hair density and length at PAW5 in maximal observed conditions were positively regulated by root developmental-related genes including COBRA-LIKE9 (COBL9), XYLOGLUCAN ENDOTRANSGLUCOSYLASE/HYDROLASE9 (XTH9), XTH17, AUXIN1 (AUX1) and LIKE-AUXIN (LAX3).

Highlights

Low-temperature, atmospheric pressure, plasma technology has emerged as a new technology that potentially enhances plant growth and defense [1,2,3]
When these NOx react with H2 O, they become ionized into NO2and NO3, which were detected in the Plasma-activated water (PAW)
The plasma-activated water samples in this paper are denoted as PAW5 time in minutes, PAW7, PAW12, PAW19 and PAW40 with the number indicating the plasma treatment time

Summary

Introduction

Low-temperature, atmospheric pressure, plasma technology has emerged as a new technology that potentially enhances plant growth and defense [1,2,3]. Treatment changes the chemical properties, and PAW containing an altered chemical composition is utilized with plants [5,6]. In this indirect method, the development of lowtemperature plasma technology is used for plant cultivation in agronomy [7,8,9]. PAW has differences in electrical conductivity, pH, nitrite, nitrate and H2 O2 compared with deionized water (DW). As for the application of PAW in plants, ionized oxygen and nitrogen species dissolve in the water to create an acidic environment due to a lower pH [10,11]

Methods

Results

Discussion

Conclusion