SlWRKY30 and SlWRKY81 synergistically modulate tomato immunity to Ralstonia solanacearum by directly regulating SlPR-STH2 .

Bacterial wilt is a devastating disease of tomato () caused by that severely threatens tomato production. Group III WRKY transcription factors (TFs) are implicated in the plant response to pathogen infection; however, their roles in the response of tomato to infection (RSI) remain largely unexplored. Here, we report the crucial role of SlWRKY30, a group III SlWRKY TF, in the regulation of tomato response to RSI. was strongly induced by RSI. overexpression reduced tomato susceptibility to RSI, and also increased HO accumulation and cell necrosis, suggesting that SlWRKY30 positively regulates tomato resistance to RSI. RNA sequencing and reverse transcription-quantitative PCR revealed that overexpression significantly upregulated pathogenesis-related protein () genes , , , and (hereafter ///) in tomato, and these genes were directly targeted by SlWRKY30. Moreover, four group III WRKY proteins (SlWRKY52, SlWRKY59, SlWRKY80, and SlWRKY81) interacted with SlWRKY30, and silencing increased tomato susceptibility to RSI. Both SlWRKY30 and SlWRKY81 activated /// expression by directly binding to their promoters. Taking these results together, SlWRKY30 and SlWRKY81 synergistically regulate resistance to RSI by activating /// expression in tomato. Our results also highlight the potential of to improve tomato resistance to RSI via genetic manipulations.