Lysinibacillus spp.: an IAA‑producing endospore forming‑bacteria that promotes plant growth

Lysinibacillus is a bacterial genus that has generated recent interest for its biotechnological potential in agriculture. Strains belonging to this group are recognized for their mosquitocidal and bioremediation activity. However, in recent years some reports indicate its importance as plant growth promoting rhizobacteria (PGPR). This research sought to provide evidence of the PGP activity of Lysinibacillus spp. and the role of the indole-3-acetic acid (IAA) production associated with this activity. Twelve Lysinibacillus spp. Strains were evaluated under greenhouse conditions, six of which increased the biomass and root architecture of corn plants. In most cases, growth stimulation was evident at 108 CFU/mL inoculum concentration. All strains produced IAA with high variation between them (20–70 µg/mL). The bioinformatic identifcation of predicted genes associated with IAA production allowed the detection of the indole pyruvic acid pathway to synthesize IAA in all strains; additionally, genes for a tryptamine pathway were detected in two strains. Extracellular fltrates from all strain’s cultures increased the corn coleoptile length in an IAA-similar concentration pattern, which demonstrates the fltrates had an auxin-like efect on plant tissue. Five of the six strains that previously showed PGPR activity in corn also promoted the growth of Arabidopsis thaliana (col 0). These strains induced changes in root architecture of Arabidopsis mutant plants (aux1-7/axr4-2), the partial reversion of mutant phenotype indicated the role of IAA on plant growth. This work provided solid evidence of the association of Lysinibacillus spp. IAA production with their PGP activity, which constitutes a new approach for this genus. These elements contribute to the biotechnological exploration of this bacterial genus for agricultural biotechnology.

• Autores: Pantoja Guerra, Manuel Fabián; Burkett Cadena, Marleny; Mayanquer Cadena, Johanna Elizabeth; Dunlap, Christopher; Ramírez Cuartas, Camilo Andrés
• Tipo de recurso: Article of investigation
• Fecha de publicación: 2023
• Institución: Universidad de Antioquia
• Repositorio: Repositorio UdeA
• Idioma: eng
• OAI Identifier: oai:bibliotecadigital.udea.edu.co:10495/46134
• Acceso en línea: https://hdl.handle.net/10495/46134
• Palabra clave: Ácidos Indolacéticos; Indoleacetic Acids; Bacillaceae; Reguladores del Crecimiento de las Plantas; Plant Growth Regulators; Arabidopsis; Raíces de las plantas - microbiología; Plant Roots - microbiology; https://id.nlm.nih.gov/mesh/D007210; http://id.nlm.nih.gov/mesh/D001406; https://id.nlm.nih.gov/mesh/D010937; http://id.nlm.nih.gov/mesh/D017360; http://id.nlm.nih.gov/mesh/D018517; ODS 12: Producción y consumo responsables. Garantizar modalidades de consumo y producción sostenibles
• Rights: openAccess
• License: http://creativecommons.org/licenses/by/4.0/