Immune activation drives citrus Huanglongbing.

Citrus Huanglongbing (HLB), caused by the phloem-limited bacterium Candidatus Liberibacter asiaticus (CLas) and considered the most destructive citrus disease worldwide, has long been regarded as a typical bacterial infection. However, recent compelling evidence shows that CLas drives HLB through chronic effector-triggered immunity, not via direct pathogenicity, thereby redefining HLB as an immune-mediated disease (Huang et al.).