Role of Curtobacterium herbarum strain CAH5 on aluminum bioaccumulation and enhancement of Lactuca sativa growth under aluminum and drought stresses

Ecotoxicol Environ Saf. 2019 Nov 15:183:109573. doi: 10.1016/j.ecoenv.2019.109573. Epub 2019 Aug 20.

Abstract

Aluminum (Al) bioaccumulation by a novel Al and drought tolerant Curtobacterium herbarum strain CAH5 isolated from rhizosphere soil of Beta vulgaris grown in acidic Andisols were examined. The rhizobacterial strain also presented important plant growth promoting traits even with Al and drought stresses under in-vitro conditions in broth. In experiments with a 2-6 mM as initial Al concentrations, the percentages of Al removal by bacteria were 89-93% and 78-91% within 72 h incubation under the normal and drought conditions, respectively. Cytogenotoxicity assay revealed that the toxicity of Al was reduced after bioaccumulation process. In the greenhouse study, formulated bio-inoculant CAH5 significantly improves the Lactuca sativa growth under Al and drought stress by reducing oxidative stress, lipid peroxidation and Al accumulation in plant parts. Our results highlighted that strain CAH5 could be used as a promising bioresource for restoration of agricultural soil with presence of phytotoxic Al improving crop production even under drought conditions.

Keywords: Aluminum; Bioaccumulation; Curtobacterium herbarum; Cytogenotoxicity assessment; PGPR.

MeSH terms

  • Actinobacteria / metabolism
  • Actinobacteria / physiology*
  • Aluminum / metabolism*
  • Aluminum / toxicity
  • Biodegradation, Environmental
  • Caryophyllales / growth & development
  • Caryophyllales / microbiology
  • Droughts*
  • Lactuca / drug effects
  • Lactuca / growth & development*
  • Lactuca / microbiology
  • Plant Growth Regulators / metabolism
  • Plant Growth Regulators / physiology*
  • Rhizosphere
  • Soil Microbiology
  • Stress, Physiological / drug effects

Substances

  • Plant Growth Regulators
  • Aluminum