Identification and localization of putative effector proteins of the destructive citrus pathogen, Candidatus Liberibacter asiaticus.
M. PITINO (1) (1) USDA, U.S.A.

Candidatus Liberibacter asiaticus “Las” is a phloem-limited bacterial plant pathogen, and the most prevalent species of Liberibacter associated with citrus huanglongbing (HLB), a devastating disease of citrus worldwide. Although the complete sequence of the Las genome provides the basis for studying functional genomics of Las and molecular mechanisms of Las-plant interactions, the functional characterization of Las effectors remains a slow process since Las has a significantly reduced genome and remains to be cultured. Computational analysis of the Las secretome uncovered 16 putative effectors, which were subsequently expressed using an agro-infiltration transient transformation system in N. benthamiana leaves. This system allowed both the localization pattern as well as any overt phenotype to be observed. One of the 16 candidates, was localized in the chloroplast and induced cell death at 3 days post inoculation (dpi) in N. benthamiana. Moreover, this effector suppressed pathogen-associated molecular patterns (PAMP)-triggered immunity (PTI) induction by Xcc-flg22. The knowledge obtained from this Las effector screen not enhances our understanding of HLB but it may also aid in the development of new and more efficient management strategies.

Abstract Number: P17-587
Session Type: Poster