title: Low-Pressure Plasma Application for the Inactivation of the Seed-borne Pathogen Xanthomonas campestris.
abstract: The aim of this study was to investigate the effect of low-pressure plasma treatment on seed disinfection and the possible mechanisms underlying this effect. Seed-borne disease refers to plant diseases that are transmitted by seeds; seed disinfection is an important technique for prevention of such diseases. In this study, the effectiveness of low-pressure plasma treatment in the inactivation of the seed-borne plant pathogenic bacterium, Xanthomonas campestris, inoculated on cruciferous seeds, was evaluated. The highest inactivation effect was observed when the treatment voltage and argon gas flow rate were 5.5 kV and 0.5 L/min, respectively. The viable cell number of X. campestris was 6.6 log cfu/seed before plasma treatment, and decreased by 3.9 log after 5 min of treatment and by 6.6 log after 40 min. Ethidium monoazide treatment and quantitative real-time PCR results indicated that both the cell membrane and target DNA region were damaged following 5 min of plasma treatment. Although both heat and ozone were generated during the plasma treatment, the contribution of both factors to the inactivation of X. campestris was small by itself in our low-pressure plasma system. Overall, we have shown that our low-pressure plasma system has great applicability to controlling plant pathogenic bacterium contamination of seeds.
authors.affiliation: Research Institute of Environment, Agriculture and Fisheries, Osaka Prefecture.
authors.forename: Terumi
authors.initials: T
authors.lastname: Nishioka
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Takai
authors.forename: Tomoko
authors.initials: T
authors.lastname: Mishima
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Kawaradani
authors.forename: Hideo
authors.initials: H
authors.lastname: Tanimoto
authors.forename: Kiyotsugu
authors.initials: K
authors.lastname: Okada
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Misawa
authors.forename: Shinichi
authors.initials: S
authors.lastname: Kusakari
mesh_terms: D002462:Cell Membrane; D004249:DNA Damage; D004203:Disinfection / Q000379:methods; D006358:Hot Temperature; D050296:Microbial Viability; D010126:Ozone; D058626:Plasma Gases; D011312:Pressure; D012639:Seeds / Q000382:microbiology*; D016959:Xanthomonas campestris
chemical_list: D058626:Plasma Gases; D010126:Ozone