Induction of disease resistance against Botrytis cinerea in tomato (Solanum lycopersicum L.) by using electrostatic atomized water particles

This study examined the effect of electrostatic atomized water particles (EAWP) on the disease resistance of tomato against Botrytis cinerea. Disease development of B. cinerea was suppressed by EAWP pretreatment prior to pathogen inoculation. Treatment of tomato plants with EAWP resulted in the upregulation of the nitrate reductase (NR) gene, which led to the accumulation of nitric oxide (NO) and S-nitrosylated proteins in the cells. In addition, the salicylic acid (SA)-dependent chitinase 3 (CHI3) gene was rapidly induced in leaves pretreated with EAWP after the leaves were inoculated with B. cinerea. Light microscopy showed browning of the epidermal cells surrounding the inoculation sites and inhibition of fungal hyphal development in the cells. These results suggest that pretreatment of tomato leaves with EAWP inhibits the development of B. cinerea in the early stages of infection by regulating the redox flux via the NO- and SA-mediated signal transduction pathways.