Implication of limited iron acquisition by Pseudomonas cichorii strain SPC9018 in its reduced virulence on eggplant

Pseudomonas cichorii s train SPC9018 was found to produce the siderophore pyoverdine. Application of the phytosiderophore mugineic acid (MA) led to a decrease in the in vitro growth of SPC9018. MA application resulted in increased expression of fecA, which is involved in citrate-mediated iron uptake and in pyoverdine production-related pvdL and pvdR, suggesting that the MA addition may lead to iron-limited conditions in SPC9018. MA application also reduced SPC9018 growth in eggplant leaves, leading to loss of its virulence on eggplant. MA also reduced adhesion of SPC9018. Considering these results together, iron acquisition may play a specific role in SPC9018 virulence on eggplant.