Enhancement of salt tolerance in corn using Azospirillum brasilense: an approach on antioxidant systems

Abstract

Salinity has become one of the major factors limiting agricultural production. In this regard, different cost-effective management strategies such as the use of plant growth-promoting bacteria (PGPB) as inoculants to alleviate salt-stress conditions and minimize plant productivity losses have been used in agricultural systems. The aim of this study was to characterize induced antioxidant responses in corn through inoculation with Azospirillum brasilense and examine the relationship between these responses and the acquired salt-stress tolerance. Treatments were performed by combining sodium chloride (0 and 100 mM NaCl) through irrigation water with absence and presence of A. brasilense inoculation. The experiment was performed in a completely randomized design with four replications. Lipid peroxidation (malondialdehyde [MDA]), and nitrogen (N), sodium (Na + ) and potassium (K + ) contents, as well as dry biomass, glycine betaine, and antioxidant enzymes activities such as of superoxide dismutase (SOD, EC 1. 15. 1. 1), glutathione reductase (GR, EC 1. 6. 4. 2), guaiacol peroxidase (GPOX, EC 1. 11. 1. 7), and glutathione peroxidase (GSH-PX, EC 1. 11. 1. 9) were determined. Overall results indicated that plants treated with 100 mM NaCl showed the most pronounced salt-stress damages with consequent increase in MDA content. However, inoculated plants showed an enhanced capacity to withstand or avoid salt-stress damages. These results could be attributed, at least in part, to the increased activity of antioxidant enzymes. Our results suggest that A. brasilense may confer tolerance to salt stress in corn plants enhancing antioxidant responses, primarily by the enzymes GSH-PX and GPOX, and the osmolyte glycine betaine.

Interactive effects of Pseudomonas putida and salicylic acid for mitigating drought tolerance in canola (Brassica napus L.)

“…Abdel Latef et al [ 89 ] also documented that the inoculation of Azotobacter chroococcum enhanced the activity of ascorbate peroxidase, catalase, and peroxidase in maize under stress conditions. Checchio et al [ 90 ] documented that inoculation of Azospirillum enhanced the production of superoxide dismutase, glutathione peroxidase, guaiacol peroxidase, glutathione reductase in maize under stress conditions. The use of Pseudomonas strains also enhance the production of antioxidants in plants.…”

Maize Seed Germination Under Low-Temperature Stress Impacts Seedling Growth Under Normal Temperature by Modulating Photosynthesis and Antioxidant Metabolism

“…The content of thiobarbituric acid (TBA) reactive substances (TBARS) can be used to assess lipid peroxidation ( Checchio et al, 2021 ). In this study, lipid peroxidation was detected using a commercial kit (Comin, Suzhou, China).…”

Photosynthesis and antioxidant metabolism modulate the low-temperature resistance of seed germination in maize

“…Lipid peroxidation was determined using a commercial kit (Comin, Suzhou, China) as previously described (Checchio et al, 2021). Briefly, Add 0.1 g tissue to the 1 mL extract, take out the 90 μL sample extract, add the reagent-900 μL, and mix the reagent two 300 μL immediately and heated at 95°C in a water bath for 1 h, and then the absorbance of the centrifuged supernatant solution was measured at 532 nm.…”