Pseudoneobacillus rhizolycopersici sp. nov., a novel multifunctional rhizobacterium for the biocontrol of tomato bacterial wilt

A novel Gram-stain-positive, rod-shaped bacterium with peritrichous flagella, designated C159 ^T , was isolated from tomato rhizosphere soil. Growth of strain C159 ^T occurred at 4–45 °C, pH 6.0–10.0 and in the presence of 0–5% NaCl. Based on 16S rRNA gene sequence analysis, strain C159 ^T belongs to the genus Pseudoneobacillus and has a sequence similarity of 98.70% with Pseudoneobacillus rhizosphaerae JJ-79 ^T . The whole genome of strain C159 ^T was 4.65 Mb, with a DNA G+C content of 38.65 mol%. The average nucleotide identity between strain C159 ^T and P. rhizosphaerae JJ-79 ^T was 75.31%, and the digital DNA–DNA hybridization value was 19.6%, supporting its designation as a novel species of the genus Pseudoneobacillus . The major respiratory quinone of strain C159 ^T was menaquinone 7; the major fatty acids were iso-C _14:0 , iso-C _15:0 and anteiso-C _15:0 ; and the major polar lipids are diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. Based on its phenotypic, chemotaxonomic, phylogenetic and genomic characteristics, strain C159 ^T represents a novel species in the genus Pseudoneobacillus , for which the name Pseudoneobacillus rhizolycopersici sp. nov. is proposed. The type strain is C159 ^T (=GDMCC 1.5552 ^T =KCTC 43820 ^T ). In addition, strain C159 ^T possesses the ability to produce indole-3-acetic acid (33.72 mg·l ⁻¹ ) and to mineralize insoluble organic phosphorus. In a pot experiment, this strain demonstrated a plant growth-promoting effect of 22.68–44.49% and a disease suppression efficacy of 89.29% against bacterial wilt of tomato caused by Ralstonia solanacearum . The above results confirm that strain C159 ^T is a novel multifunctional rhizobacterium for the biocontrol of tomato bacterial wilt.