Plant growth promoting rhizobacteria induced metal and salt stress tolerance in Brassica juncea through ion homeostasis

Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved..

Soil heavy metal contamination and salinity constitute a major environmental problem worldwide. The affected area and impact of these problems are increasing day by day; therefore, it is imperative to restore their potential using environmentally friendly technology. Plant growth-promoting rhizobacteria (PGPR) provides a better option in this context. Thirty-seven bacteria were isolated from the rhizosphere of maize cultivated in metal- and salt-affected soils. Some selected bacterial strains grew well under a wide range of pH (4-10), salt (5-50 g/L), and Cd (50-1000 mg/L) stress. Three bacterial strains, Exiguobacterium aestuarii (UM1), Bacillus cereus (UM8), and Bacillus megaterium (UM35), were selected because of their robust growth and high tolerance to both stress conditions. The bacterial strains UM1, UM8, and UM35 showed P-solubilization, whereas UM8 and UM35 exhibited 1-aminocyclopropane-1-carboxylate deaminase activity and indole acetic acid (IAA) production, respectively. The bacterial strains were inoculated on Brassica juncea plants cultivated in Cd and salt-affected soils due to the above PGP activities and stress tolerance. Plants inoculated with the bacterial strains B. cereus and B. megaterium significantly (p < 0.05) increased shoot fresh weight (17 ± 1.17-29 ± 0.88 g/plant), shoot dry weight (2.50 ± 0.03-4.40 ± 0.32 g/plant), root fresh weight (7.30 ± 0.58-13.30 ± 0.58 g/plant), root dry weight (0.80 ± 0.04-2.00 ± 0.01 g/plant), and shoot K contents (62.76 ± 1.80-105.40 ± 1.15 mg/kg dwt) in normal and stressful conditions. The bacterial strain B. megaterium significantly (p < 0.05) decreased shoot Na+ and Cd++ uptake in single and dual stress conditions. Both bacterial strains, E. aestuarii and B. cereus, efficiently reduced Cd++ translocation and bioaccumulation in the shoot. Bacterial inoculation improved the uptake of K+ and Ca++, while restricted Na+ and Cd++ in B. juncea shoots indicated their potential to mitigate the dual stresses of salt and Cd in B. juncea through ion homeostasis.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:267

Enthalten in:

Ecotoxicology and environmental safety - 267(2023) vom: 15. Nov., Seite 115657

Sprache:

Englisch

Beteiligte Personen:

Daraz, Umar [VerfasserIn]
Ahmad, Iftikhar [VerfasserIn]
Li, Qu-Sheng [VerfasserIn]
Zhu, Bo [VerfasserIn]
Saeed, Muhammad Farhan [VerfasserIn]
Li, Yang [VerfasserIn]
Ma, Jianguo [VerfasserIn]
Wang, Xiao-Bo [VerfasserIn]

Links:

Volltext

Themen:

00BH33GNGH
Brassica juncea
Cadmium
Journal Article
Metal stress
Nutrient availability
PGPR
Salt-stress
Soil

Anmerkungen:

Date Completed 27.11.2023

Date Revised 27.11.2023

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.ecoenv.2023.115657

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM364166517