Paper PB+BI+PS-TuM10
Control of Plant Growth by RONS Produced Using Nonthermal Atmospheric Air Plasma
Tuesday, November 8, 2016, 11:00 am, Room 101A
Nonthermal atmospheric plasmas have been widely used for biomedical applications because of their non-equilibrium feature and synergy effects [1-3]. The non-equilibrium feature allows us to introduce reactive oxygen and nitrogen species (RONS) to biomaterials with a significantly wide dose range compared with the conventional irradiation methods such as X-ray and γ-ray [4]. For an agricultural application, we succeeded in reducing harvest period and enhancing crop yield by plasma irradiation to plant seeds [5]. We found irradiation of RONS with an appropriate dose to seeds brings about growth enhancement in all growth stages of plants. To understand the growth enhancement mechanism, here we have studied dependence of irradiation dose of RONS produced by plasma to seeds on growth of Arabidopsis thaliana L. Experiments were carried out using a scalable DBD device [2, 3, 5]. The device consisted of 20 electrodes of a stainless rod of 1 mm in outer diameter and 60 mm in length covered with a ceramic tube of 2 mm in outer diameter. The discharge voltage and current were 9.2 kV and 0.2 A. 20 seeds of Arabidopsis thaliana L. were set 3 mm below the electrodes. The RONS dose was controlled by the irradiation time. After plasma irradiation, they were grown on soil tab in incubators. To evaluate plant growth, the stem length was measured as a function of cultivation days. The stem length was normalized by the stem length of the plants without plasma irradiation. To evaluate statics of the measured values, we used a two-tailed ANOVA statistically significance different at α= 0.05 (ｐ< 0.05). The normalized stem length increases to 1.3 for 3 min irradiation, then decreases to zero for 10 min irradiation. The results indicate the plant growth is activated by plasma irradiation less than 3 min and inactivated by plasma irradiation of 5-10 min. Above 10 min irradiation, no seeds were germinated. We have succeeded in growth control of plants from death to activation with irradiation dose of RONS produced by plasma. The mechanism will be discussed in the presentation. [1] J. Raiser and M. Zenker, J. Phys. D, 39, 3520 (2006).
[2] T. Sarinont, et al., JPS Conf. Proc. 1, 015078 (2014).
[3] S. Kitazaki, et al., Curr. Appl. Phys., 14, S149 (2014).
[4] A. Pankaj, et al., Scientific Reports, 5, 17781 (2015).
[5] K. Koga et al., Appl. Phys. Express, 9, 16201 (2016).