A natural variant of X. citri, as potential biocontrol of pathogens in citrus

UVIEDO, F.; FAVARO, M.A.; GADEA, J.; ROESCHLIN, R.A.; MOLINA, C.; GMITTER JR., F; GARCIA, L.; TASSELLI, S.; MARANO, M.R.

Florida

Conferencia; V International Research Conference on Huanglongbing; 2017

University of Florida-USDA

Xanthomonas citri ssp. citri (X. citri) strain A is the causative agent of Asiatic citrus canker, a disease that seriously affects most commercially important Citrus spp. worldwide. We have previously identified a natural variant, X. citri AT, that triggers a host-specific defense response in Citrus limon. Characterization of this response shown that X. citri AT triggers a hypersensitive response (HR) associated with the interference on biofilm development and the activation of autophagy-related vacuolar processes. Moreover, this plant response involves an extensive transcriptional reprogramming setting in motion cell wall reinforcement, oxidative burst and accumulation of salicylic acid (SA) and phenolic compounds. Interestingly, we demonstrate that this defense response protects C. limon plants from disease upon subsequent challenges by pathogenic X. citri. Further studies are required to explore if this defense response decreases susceptibility to other citrus pathogens, including Huanglongbing (HLB).