Document Type : Research Paper

Authors

• Somayeh Mohammadi ¹
• Elaheh Vatankhah ²
• Setareh Amanifar ³
• Zohreh Toghranegar ⁴

¹ Department of Biology, Faculty of Sciences, University of Zanjan, Iran

² Department of Biology, Faculty of Science, University of Zanjan

³ Department of Soil Science, Faculty of Agriculture, University of Zanjan, Zanjan, Iran

⁴ Department of Biology, Faculty of Sciences, University of Zanjan, Zanjan, Iran

Abstract

The symbiotic relationship between arbuscular mycorrhizal fungi and the roots of higher plants plays an important role in their tolerance to water stress. To investigate the effect of mycorrhizal symbiosis on water content and antioxidant system of licorice (Glycyrrhiza glabra L.) under water deficit stress, a factorial completely randomized experiment was conducted with two factors: (1) mycorrhizal inoculation with Funneliformis mosseae and without inoculation, and (2) soil moisture levels of 100% (control), 70%, and 50% of field capacity (FC). The results showed that water deficit stress decreased relative leaf water content and plant dry weight and mycorrhizal colonization improved these growth parameters. Biochemical analyses also showed that mycorrhizal symbiosis significantly decreased the contents of proline and malondialdehyde at two stress levels and phenol at FC50% level compared to non-mycorrhizal plants. The flavonoid content of mycorrhizal plants was higher than non-mycorrhizal ones at FC50% level. In addition, F. mosseae symbiosis significantly reduced the activities of ascorbate peroxidase and polyphenol oxidase in shoot and root, and peroxidase in shoot at all moisture levels in comparison with non-colonized plants. Wherease, mycorrhizal symbiosis led to a significant increase in the activities of catalase and peroxidase in root at 50% FC level, and activities of superoxide dismutase and catalase in the shoot at 70% FC level. In general, the results showed that the symbiosis of licorice with F. mosseae mitigated the detrimental effects of water deficit stress by improving plant water content and regulating the response of enzymatic and non-enzymatic antioxidant defense system.

Keywords

• antioxidant enzymes and metabolites
• water deficit stress
• Licorice
• arbuscular mycorrhizal fungus
• relative leaf water content

Main Subjects

• Physiology