A nonproteinaceous <i>Fusarium</i> cell wall extract triggers receptor‐like protein‐dependent immune responses in Arabidopsis and cotton

Fusarium wilt caused by the ascomycete fungus oxysporum is a devastating disease of many economically important crops. The mechanisms underlying plant responses to F. infections remain largely unknown. We demonstrate here that water-soluble, heat-resistant and nonproteinaceous cell wall extract (FoCWE) component from multiple isolates functions as race-nonspecific elicitor, also termed pathogen-associated molecular pattern (PAMP). FoCWE triggers several demonstrated immune responses, including mitogen-activated protein (MAP) kinase phosphorylation, reactive oxygen species (ROS) burst, ethylene production, stomatal closure, in cotton Arabidopsis. Pretreated protects seeds against virulent f. sp. vasinfectum (Fov), Arabidopsis plants bacterium, Pseudomonas syringae, suggesting potential application FoCWEs crop protection. Host-mediated do not appear require LYKs/CERK1, BAK1 or SOBIR1, which are commonly involved PAMP perception and/or signalling. However, resistance partially two receptor-like proteins, GhRLP20 GhRLP31. Transcriptome analysis suggests preferentially activates wall-mediated defence, Fov has evolved virulence suppress FoCWE-induced defence. These findings suggest classical potentially recognised novel pattern-recognition receptor regulate infections.