Microbial amelioration of salinity stress in endangered accessions of Iranian licorice (Glycyrrhiza glabra L.)

Seyyed Sasan Mousavi; Akbar Karami; Mohammad Jamal Saharkhiz; Mohammad Etemadi; Mohammadhossein Ravanbakhsh

doi:10.1186/s12870-022-03703-9

Microbial amelioration of salinity stress in endangered accessions of Iranian licorice (Glycyrrhiza glabra L.)

BMC Plant Biol. 2022 Jul 5;22(1):322. doi: 10.1186/s12870-022-03703-9.

Authors

Seyyed Sasan Mousavi¹, Akbar Karami², Mohammad Jamal Saharkhiz¹, Mohammad Etemadi¹, Mohammadhossein Ravanbakhsh³

Affiliations

¹ Department of Horticultural Science, School of Agriculture, Shiraz University, Shiraz, Iran.
² Department of Horticultural Science, School of Agriculture, Shiraz University, Shiraz, Iran. akarami2004@gmail.com.
³ Institute of Environmental Biology, Ecology and Biodiversity Group, Utrecht University, Utrecht, Netherlands.

Abstract

Background: Glycyrrhiza glabra L. is a medicinal and industrial plant that has gone extinct due to different abiotic stress caused by climate change. To understand how the plant-associated microorganism can support this plant under salinity, we collected sixteen Iranian accessions of G. glabra L., inoculated their rhizomes with Azotobacter sp. (two levels, bacterial treatments, and no-bacterial treatments, and grown them under salinity stress (NaCl levels; 0, and 200 mM).

Results: Two accessions of Bardsir and Bajgah significantly showed higher resistant to salinity, for example by increasing crown diameter (11.05 and 11 cm, respectively) compared to an average diameter of 9.5 in other accessions. Azotobacter inoculation caused a significant increase in plant height and crown diameter. Among studied accessions, Kashmar (46.21%) and Ilam (44.95%) had the highest rate of membrane stability index (MSI). Evaluation of enzyme activity represented that bacterial application under salinity, increased polyphenol oxidase (PPO) (0.21 U mg^-1 protein), peroxidase (POD) (3.09 U mg^-1 protein U mg^-1 protein), and phenylalanine ammonia-lyase (PAL) (17.85 U mg^-1 protein) activity. Darab accession showed the highest increase (6.45%) in antioxidant potential compared with all studied accessions under Azotobacter inoculation. According to principal component analysis (PCA), it was found that the accession of Meshkinshahr showed a more remarkable ability to activate its enzymatic defense system under salt stress. Also, three accessions of Meshkinshahr, Eghlid, and Ilam were categorized in separated clusters than other accessions regarding various studied treatments.

Conclusion: Analysis indicated that five accessions of Meshkinshahr, Rabt, Piranshahr, Bardsir, and Kermanshah from the perspective of induced systematic resistance are the accessions that showed a greater morphophysiological and biochemical outcome under salinity. This study suggested that, inoculation of with Azotobacter on selected accession can relieve salt stress and support industrial mass production under abiotic condition.

Keywords: Antioxidant Enzymes; Azotobacter; Licorice Population; Plant Growth-Promoting Rhizobacteria; Salt Stress.

MeSH terms

Azotobacter*
Endangered Species
Glycyrrhiza* / microbiology
Glycyrrhiza* / physiology
Iran
Salt Stress*
Triterpenes*

Substances

Triterpenes