The Potency of Plant Resistance Inducers (Pris) Against Bacterial Wilt Disease on Tobacco Caused by Ralstonia Solanacearum

Abstract

The tobacco plant (Nicotiana tobaccum L) is one of the most valuable crops in Jember, Indonesia. One of the destructive diseases of tobacco is bacterial wilt disease caused by Ralstonia solanacearum. Plant resistance inducer (PRI) agents such as Pseudomonas fluorescens, flagella, and salicylic acid are known to have the potency to control plant pathogens by inducing a mechanism of resistance in the plant. However, there is still no study comparing their effectiveness in controlling bacterial wilt disease. This research aimed to study the effectiveness of each PRI in controlling tobacco bacterial wilt disease. The molecular assay using Polymerase Chain Reaction (PCR) confirmed that FTb4 bacteria is R. solanacearum and used either as inoculum or as a PRI flagella source. In addition, P. fluorescens IC1 was isolated from a pepper plant rhizosphere in Jember. PRIs (Isolate IC1, FTb4 flagella, and salicylic acid) were applied to control bacterial wilt disease. In vivo results showed that treatment of PRIs with medium-resistant criteria at 7 days before pathogen inoculation successfully suppressed disease incidence up to 90-93 % and disease severity up to 33.33 %. Usage of PRIs on tobacco plants increased peroxidase activity and total phenol production, indicating that PRIs induced plant resistance.