Evaluation of an Oxidant Disinfectant's Ability to Prime Plant Defenses for Systemic Acquired Resistance in Light Red Kidney Bean Plants Inoculated with Common Bean Bacterial Wilt

Plants are susceptible to a wide range of pathogens that can be detrimental to the horticulture industry. Pathogens can result in killing plants causing major losses in production or it can result in plants being unsaleable. Plants naturally have a plant defense system that can protect themselves against an attack from pathogens. This immunity is triggered only when the plant is being attacked due to it taking energy and resources. Plants can be primed with abiotic measures to induce plant defenses resulting in a systemic acquired resistance (SAR) against a wide range of pathogens. This primed state results in a stronger and faster response when an attack does take place. An important hormone that activates pathogenesis related proteins for defense for pathogens is salicylic acid (SA). SA activates proteins that aid in killing the pathogen, isolating the pathogen from spreading and signaling the danger of the attack to the rest of the plant. Light red kidney bean plants were treated with Electro-Biocide^TM (E-B) a proprietary blend of Chlorine dioxide, surfactant and pH buffer. The study’s objective was to investigate if SAR can be obtained by E-B spray treatments. E-B was investigated for horticultural use for this study due to it having a safe Environmental Protection Agency rating of IV, a pH buffer making it non-corrosive, ease of use as a foliar spray application and its oxidizing power to sanitize surfaces. The following rates were evaluated: E-B 0 ppm (control), E-B 200 ppm and E-B 400 ppm. In addition to E-B, a commercially available product Actigard^TM that has been proven successful at inducing systemic acquired resistance was evaluated as well. Spray treatments were replicated with non-inoculated plants and inoculated plants with a wilt disease caused by Curtobacterium flaccumfaciens pv. flaccumfaciens. Leaves were collected 5 days after treatment (DAT) for SA measurements and again at 43 DAT. SA was measured by liquid chromatography tandem-mass spectrometry (LC-MS/MS). At 5 DAT for both inoculated and non-inoculated plants the results showed that E-B 200 and 400 treatments had significantly higher concentrations of SA when compared to Actigard^TM and the control. This indicates that the plants treated with E-B were primed. Results at 43 DAT showed non-inoculated plant’s treatments went down back to normal range of SA and that inoculated treatments SA concentrations continued to rise. E-B shows promise of an easy and safe foliar treatment for horticulturalist to proactively combat diseases before an infection happens.