A new plant commensal Pseudomonas veronii isolate (strain R4) was identified from a Xiphinema index biocontrol screen. Isolated from grapevine roots from vineyards in central Chile, the strain R4 exhibited a slower yet equivalently effective nematicide activity as the well-characterized P. protegens CHA0. Whole genome sequencing of strain R4 and comparative analysis among the available Pseudomonas spp. genomes allowed for the identification of gene clusters that encode putative extracellular proteases and lipase synthesis and secretion systems, which are proposed to mediate-at least in part-the observed nematicidal activity. In addition, R4 strain presented relevant gene clusters related to metal tolerance, which is typical in P. veronii. Bioinformatics analyses also showed gene clusters associated with plant growth promoting activity, such as indole-3-acetic acid synthesis. In addition, the strain R4 genome presented a metabolic gene clusters associated with phosphate and ammonia biotransformation from soil, which could improve their availability for plants.
Keywords: Biocontrol; Exolipases; Exoproteases; Pseudomonas spp.; Pseudomonas veronii; Vitis vinifera L; Xiphinema index.