ABSTRACT
The selective autophagy receptor NEIGHBOUR OF BRCA1 (NBR1) is a key regulator of plant immunity, but its role against bacterial pathogens remains poorly understood. Here, we demonstrated that overexpression of
CsNBR1
confers citrus resistance to huanglongbing (HLB) caused by ‘
Candidatus
Liberibacter asiaticus’ (
C
Las). CsNBR1 can interact with multiple virulence effector proteins of
C
Las, including SDE5115, SDE1, SDE19 and SDE5, leading to their degradation via the autophagic pathway. In addition, expression of
CsNBR1
in
Nicotiana benthamiana
mitigated the leaf curling and dwarfing phenotypes triggered by SDE1 by reducing the protein content of SDE1. These findings reveal that CsNBR1 positively regulates citrus defence against
C
Las by degrading its effector proteins via selective autophagy, providing both mechanistic insights and a potential target for resistance breeding.