Co-inoculation of Bacillus velezensis and Stenotrophomonas maltophilia strains improves growth and salinity tolerance in maize (Zea mays L.)

• Published in: Rhizosphere 2023-09, Vol.27, p.100752, Article 100752
• Main Authors: Ercole, Tairine Graziella, Kava, Vanessa Merlo, Aluizio, Rodrigo, Pauletti, Volnei, Hungria, Mariangela, Galli-Terasawa, Lygia Vitoria
• Format: Article
• Language: English
• Subjects: Bioprospection; Inoculant; PGPB; Rhizobacteria; Saline stress
• ISSN: 2452-2198; 2452-2198
• DOI: 10.1016/j.rhisph.2023.100752

Limiting factors for plant growth, such as low nutrient availability and intolerance to high salinity, may impair the production of several crops. Plant growth-promoting bacteria (PGPB) present a potential solution to mitigate these limitations by stimulating plant growth and development. This study aimed to identify the strains LGMB12, LGMB319, and LGMB426 (Bacillus velezensis) and LGMB417 (Stenotrophomonas maltophilia), and to assess single and co-inoculation effects of these bacteria on the growth promotion of maize (Zea mays L.) plants under normal conditions and in high salinity environments. These strains were identified through Bayesian inference multilocus analysis using 16 S rRNA, gyrA, recA, and rpoB genes. Antibiosis analysis revealed that the strains did not inhibit each other's growth. Thirteen inoculation conditions were tested in greenhouse experiments including controls, inoculation of each strain separately and in the six pairs of combinations to evaluate growth promotion and salinity tolerance, using 75 and 100 mM NaCl in the irrigation water. The results revealed that co-inoculation yielded the best outcomes, highlighting the synergistic effects of combining the strains. Overall, this study emphasizes the potential of co-inoculation with Bacillus velezensis and Stenotrophomonas maltophilia strains as a strategy to enhance plant growth and improve salinity tolerance in maize cultivation. Further investigations are warranted to explore their application as bioinputs in agricultural settings. [Display omitted] •Co-inoculation of endophytic bacteria enhances maize growth in the greenhouse.•Bacillus velezensis isolated in Brazil showed outstanding results for PGPB.•Stenotrophomonas maltophilia with Bacillus velezensis mitigated salt stress in maize.•Bioinputs based on PGPB are a path to sustainable agriculture.•Bioprospecting studies are the key to finding promising strains for new inoculants.