Genome-wide identification of adaptive genes in Pseudomonas syringae pv. actinidiae under host and non-host environments

Pseudomonas syringae pv. actinidiae (Psa) is the causative agent of kiwifruit canker disease, posing a significant constraint on industrial kiwifruit development. Psa pathogenesis involves establishing an epiphytic presence on leaf surfaces, invading host tissue through natural openings or wounds, and proliferating in the apoplast to cause disease. Psa also elicits a hypersensitive response (HR) in the non-host Nicotiana benthamiana, indicating its adaptive mechanisms in diverse environments. However, the genetic basis of Psa adaptation to host and non-host settings remains unclear. This study aimed to systematically investigate Psa niche adaptation strategies by performing genome-wide transposon-insertion sequencing (Tn-seq).