Expression of defense signaling genes in the potato-Verticillium dahliae interaction

Abstract

Verticillium dahliae Kleb. causes Verticillium wilt in potato (Solanum tuberosum L.). Hormone signaling pathways are known to play a role in plant defense reactions. A gene expression analysis was performed on a susceptible and a moderately resistant (MR) cultivar of potato after inoculation with either a highly aggressive (HA) or a weakly aggressive (WA) isolate of V. dahliae. Genes related to the salicylic acid (SA), jasmonic acid/ethylene (JA/ET), and abscisic acid (ABA) pathways showed higher expression in the MR cultivar than the susceptible cultivar indicating that they may contribute to resistance. Additionally, a number of genes showed a delayed reaction in the susceptible cultivar and only in plants inoculated with the HA isolate of the pathogen. This trend was observed in genes related to the SA and JA/ET pathways. Overall, this research indicates that more than one hormone signaling pathway may contribute to the defense against V. dahliae by potato.