Biocontrol-relevant diversity of wheat-associated <i>Pseudomonas</i> : prevalence of <i>P. sivasensis</i> and identification of the novel species <i>P. arvensis</i> sp. nov.

The role of microbial communities in plant health and productivity has become increasingly evident. In this study, we investigated the diversity and functional potential of <i>Pseudomonas</i> spp. associated with Belgian cereal crops, focusing on wheat and spelt. From 444 <i>Pseudomonas</i> isolates, we identified 11 species, with several strains exhibiting strong antagonistic activity against major wheat pathogens. Notably, we report the high prevalence and efficient colonization abilities of <i>Pseudomonas sivasensis</i>, including its capacity to translocate from seed to leaf and suppress <i>Zymoseptoria tritici</i> infection <i>in planta</i>. Furthermore, we describe <i>Pseudomonas arvensis</i> sp. nov., a newly characterized species within the wheat microbiome, with DR1PS3 designated as the type strain. Our results advance the understanding of beneficial plant-microbe interactions in cereals and highlight the promise of native <i>Pseudomonas</i> species as biocontrol agents for sustainable disease management.