Phylogenetic relationships and pathogenicity of Agrobacterium in Cinnamomum camphora

Abstract

Camphor trees (Cinnamomum camphora) are renowned for their natural resistance to bacterial diseases resulting from their production of camphor, a bioactive compound with antimicrobial properties. Despite extensive research on Agrobacterium as a soil-borne plant pathogen, its association with camphor trees has not been previously documented. To address this research gap, we investigated the potential interactions between Agrobacterium and camphor trees by isolating Agrobacterium strains using a copper-containing medium screening method. A molecular phylogenetic analysis of 16S rDNA sequences was employed to identify and characterize the isolates. The Agrobacterium strains formed a distinct phylogenetic cluster closely related to Agrobacterium cavarae derived from maize (Zea mays L.) roots and Agrobacterium larrymoorei derived from Ficus benjamina. These findings provide the first evidence of Agrobacterium in association with camphor trees, thereby expanding our understanding of plant-microbe interactions and highlighting a potentially unexplored aspect of Agrobacterium ecology. This work underscores the importance of investigating plant-associated microbial communities, particularly in species with unique antimicrobial traits.