Application of acetylsalicylic acid (aspirin) solution affects plant resistance against psyllids carrying Candidatus Liberibacter solanacearum

Plants are adapted to reduce damages imposed by pathogens and insects. To mitigate incidences of herbivory and disease, plant induce specific responses. Plant responses to the pathogen ‘Candidatus Liberibacter solanacearum’ and its vector Bactericera cockerelli are not well understood. However, salicylic acid (SA) defense pathway have been associated with induced systemic acquired resistance against phloem-feeding herbivores like B. cockerelli. Here, we applied a potential SA elicitor, acetylsalicylic acid (ASA) or water (Control) solutions on tomato plants to (1) study the effect of plant induced resistance, (2) observe plant performance in response to the elicitor, and (3) examine vectors pattern of oviposition. Choice and no-choice bioassays were conducted using vectors harboring the pathogen. The results showed that the higher the concentration of ASA solution applied the lower the number of vectors on plants. Even at a low concentration, ASA solution reduced total number of vectors on plants compared to the water solution. Low concentration of ASA did not affect plant growth and overall biomass when compared to the control. This indicates that ASA solution can increase plant resistance by lowering pest number without affecting plant performance. Thus, plant defense elicitor can potentially be used to induce plant resistance for the management of pests and diseases.