Massilia rhizosphaerae sp. nov., a rice-associated rhizobacterium with antibacterial activity against Ralstonia solanacearum

Abstract

A novel rhizobacterium, designated strain NEAU-GH312T, with antibacterial activity against Ralstonia solanacearum was isolated from rhizosphere soil of rice (Heilongjiang Province, PR China) and characterized with a polyphasic approach. Cells of strain NEAU-GH312T were Gram-stain-negative, aerobic, non-spore-forming, motile with peritrichous flagella and rod-shaped. Colonies were light orange, convex and semi-translucent on Reasoner's 2A (R2A) agar after 2 days of incubation at 28 °C. Growth was observed on R2A agar at 10–40 °C, pH 4.0–8.0 and with 0–5 % (w/v) NaCl. The respiratory quinone was ubiquinone Q-8. The major cellular fatty acids of strain NEAU-GH312T were C16 : 1 ω7c and/or C16 : 1 ω6c, C16 : 0 and C18 : 1 ω7c and/or C18 : 1 ω6c. The main polar lipids were phosphatidylglycerol, phosphatidylethanolamine and diphosphatidylglycerol. Phylogenetic analyses confirmed the well-supported affiliation of strain NEAU-GH312T within the genus Massilia , close to the type strains of Massilia arvi THG-RS2OT (98.7 %), Massilia norwichensis NS9T (98.7 %) and Massilia kyonggiensis TSA1T (98.6 %). Strain NEAU-GH312T had a genome size of 6.68 Mb and an average DNA G+C content of 66.3 mol%. Based on the genotypic, phenotypic and chemotaxonomic data obtained in this study, strain NEAU-GH312T could be classified as representative of a novel species of the genus Massilia , for which the name Massilia rhizosphaerae sp. nov. is proposed, with strain NEAU-GH312T (=DSM 109722T=CCTCC AB 2019142T) as the type strain.

Molecular Biodiversity of Bacteria Isolated from Medicago sativa Rhizosphere in Haʼil District, Saudi Arabia

“…As mentioned above in this study one of our isolates related to Arthrobacter pascens according to sequences analysis which was reported before to produce a growth-promoting substance (29). In addition, Arthrobacter pascens isolated from the rhizosphere of forest soil in China reported a salt-tolerant bacterial strain, that secretes IAA, dissolves inorganic phosphorus, and degrades persistent organic (POPs) pollutants like polycyclic aromatic hydrocarbons (PAHs) such as fluoranthene (30). Like that, Arthrobacter globiformis to which Pseudarthrobacter Hai'l2 is related was isolated from a cave deposit in India and contained biosynthetic genes for encoding putative secondary metabolites and other antibiotics and showed antimicrobial activity (31).…”

“…In addition to the role, the isolates in this study are expected to play in the environment, Massilia spp. were found to play role in the biological control of fungi like Massilia rhizosphaerae which was recently isolated from rhizosphere soil of rice and characterized as Gram-stain-negative and show antibacterial activity (30).…”

“…The compounds in the substances left by the roots, by acidifying or changing the redox conditions in the rhizosphere or directly chelating the elements, help to provide nutrients such as nitrogen, phosphorus, iron, etc. As the soil dries, the hydraulic potential decreases, after which the root seepage begins to return water to the soil, increasing the degree of stability of the rhizosphere (39)(40)(41)(42)(43)(44)(45)(46)(47)(48).…”

Rhizosphere microorganisms of Crocus sativus as antagonists against pathogenic Fusarium oxysporum

“…Among the genera with negative correlation, the bacterial genus Asanoa had the closest correlation (ρ = −0.7934, p < 0.001), whereas the closest fungal genus was Moniliophthora (ρ = −0.7047, p < 0.001). In addition, genera negatively correlated with RLA included many microbes of disease resistance, such as Massilia (ρ = −0.7277, p < 0.001) ( Li et al., 2021a ), Talaromyces (ρ = −0.6398, p < 0.001) ( Tian et al., 2021c ), Burkholderia (ρ = −0.5569, p < 0.01) ( Ahmad et al., 2022 ), etc.…”

Nitrogen Fertilizer Type and Genotype as Drivers of P Acquisition and Rhizosphere Microbiota Assembly in Juvenile Maize Plants

“…These bacteria have been reported as having plant-growth-promoting capabilities through P-solubilizing ability and indole acetic acid and siderophore production [ 80 , 81 , 82 ]. Intriguingly, Massilia taxa have shown antagonism activity towards crop pathogens [ 83 , 84 ] and the capability to improve salinity tolerance in maize [ 85 ]. Likewise, putative plant-beneficial bacteria affiliated with the genus Saccharimonadales were also found to be biomarkers for the F160 rhizosphere under ammonium fertilization.…”