Colonization by arbuscular mycorrhizal fungi improves salinity tolerance of eucalyptus (Eucalyptus camaldulensis) seedlings

Abstract

Soil salinity affects soil quality and reduces plant performance. Arbuscular mycorrhizal fungi (AMF) can enhance the tolerance of plants under salinity stress. Cultivation of eucalyptus (Eucalyptus camaldulensis), which exhibits high water use efficiency, is possible in saline areas to produce raw materials for the pulp industry. We determined the effects of arbuscular mycorrhizal fungi (AMF) on the growth and survival of eucalyptus seedlings under saline conditions. Three different clones of eucalyptus seedlings were pre-inoculated with three salt-tolerant AMF species, namely Glomus sp.2, Gigaspora albida and G. decipiens, and without pre-inoculation. The seedlings were grown in a greenhouse for 45 days. They were then transferred to individual pots, filled with field soil and subsequently treated with NaCl solution until electro-conductivity (EC) reached 10, 15 and 20 dS m−1. They were watered for 90 days under nursery conditions. The results show that increased salinity levels reduced plant performance, fractional AMF root colonization, spore number, and eucalypt K/Na ratio. AMF significantly increased chlorophyll and decreased leaf proline concentrations by more than 50% and 20% respectively and increased the K/Na ratio three- to six-fold compared with non-inoculated plants. Pre-inoculation with AMF before outplanting also improved plant performance by more than 30% under salinity stress compared to non-inoculated plants. We conclude that AMF can alleviate the negative impacts of salinity on plant physiological and biochemical parameters.

Understanding the potential of root microbiome influencing salt‐tolerance in plants and mechanisms involved at the transcriptional and translational level

“…A mixture of salt-tolerant AMF, viz. Glomus sp., Gigaspora albida, and Gigaspora decipiens also conferred an enhanced degree of salt tolerance in Eucalyptus seedlings by increasing chlorophyll content and K + /Na + ratio (Klinsukon et al, 2021) plant growth and glycyrrhizin production by maintaining ion homeostasis and enhanced proline biosynthesis. Similar growth promotion activities of AMF genera Claroideoglomus claroideum and Glomus mosseae under salinity stress condition were also observed (Santander et al, 2019;Shi-chu et al, 2019).…”

“…A mixture of salt‐tolerant AMF, viz. Glomus sp., Gigaspora albida , and Gigaspora decipiens also conferred an enhanced degree of salt tolerance in Eucalyptus seedlings by increasing chlorophyll content and K + /Na + ratio (Klinsukon et al, 2021). According to Amanifar et al (2019), amelioration of salinity stress in Glycyrrhiza glabra was conferred by F. mosseae colonization, which in turn, helped to sustain plant growth and glycyrrhizin production by maintaining ion homeostasis and enhanced proline biosynthesis.…”

Effect of Rhizophagus irregularis on Growth and Quality of Cannabis sativa Seedlings

“…The addition of Plant Growth Promoting Microorganisms (PGPMs) in nutrient solutions, in float systems, could be beneficial for cannabis seedlings. Recently, studies indicated the positive impact of PGPMs on seedlings of various plant species [29][30][31][32]. PGPMs improve plant nutrition and affect the release of biologically active substances such as phytohormones, vitamins, and enzymes [33,34].…”

Co-Inoculation of an Endophytic and Arbuscular Mycorrhizal Fungus Improve Growth and Yield of Helianthus tuberosus L. under Field Condition

“…AMF, biotrophic endophytic microorganisms belonging to the phylum Glomeromycota, are a group of fungi that form symbiotic associations within plant roots [13]. Similar to EPF, AMF can help host plants to increase growth and productivity by enhancing the uptake of water and mineral nutrients, improving the soil quality, enhancing stress tolerance, and protecting against plant pathogens [14,15]. However, the distinct feature of the AMF that distinguishes them from EPF is their ability to colonize the belowground parts of plants, which was restricted to plant roots, while AMF fungi only colonized the roots.…”