The FaPSMD14–FaEIN3–FaWRKY40 module enhances strawberry resistance to Botrytis cinerea by modulating cytokinin and jasmonic acid biosynthesis

Abstract Gray mold, caused by Botrytis cinerea, severely threatens strawberry production worldwide, yet the molecular mechanisms underlying strawberry resistance remain poorly understood. Here, we show that the transcription factor ETHYLENE INSENSITIVE 3 (FaEIN3), a strawberry EIN3/EIL homolog, positively regulates strawberry resistance to B. cinerea by directly activating transcription of the WRKY transcription factor gene FaWRKY40. FaWRKY40 further induces the cytokinin biosynthesis gene FaLOG1 and the jasmonic acid biosynthesis gene FaAOC4, thereby promoting hormone accumulation and enhancing disease resistance. Moreover, the JAMM-family deubiquitinase FaPSMD14 physically interacts with FaEIN3 in the nucleus and stabilizes FaEIN3, thereby strengthening FaEIN3-mediated activation of FaWRKY40. Our findings reveal a previously uncharacterized defense mechanism in which the FaPSMD14–FaEIN3–FaWRKY40 regulatory cascade promotes strawberry resistance to B. cinerea through coordinated activation of cytokinin and jasmonic acid pathways.