Claroideoglomus etunicatum improved the growth and saline- alkaline tolerance of Potentilla anserina by altering physiological and biochemical properties

To investigate the effects of arbuscular mycorrhizal (AM) fungi on the growth and saline-alkaline tolerance of Potentilla anserina L., the seedlings were inoculated with Claroideoglomus etunicatum (W.N. Becker & Gerd.) C. Walker & A. Schussler in pot cultivation. After 90 days of culture, saline-alkaline stress was induced with NaCl and NaHCO3 solution according to the main salt components in saline-alkaline soils. Based on the physiological response of P. anserina to the stress in the preliminary experiment, the solution concentrations of 0 mmol/L, 75 mmol/L, 150 mmol/L, 225 mmol/L and 300 mmol/L were treated with stress for 10 days, respectively. The mycorrhizal colonization rate, mycorrhizal dependence, chlorophyll content, malondialdehyde content, antioxidant enzyme activities, osmoregulation substances content and water status were measured. The results showed that with the increase of NaCl and NaHCO3 stress concentration, mycorrhizal colonization rate, colonization intensity, arbuscular abundance and vesicle abundance decreased, and reached the lowest value at 300 mmol/L. Strong mycorrhizal dependence was observed after the symbiosis with AM fungus, and the dependence was higher under NaHCO3 treatment. Under NaCl and NaHCO3 stress, inoculation with AM fungus could increase chlorophyll content, decrease malondialdehyde content, increase activities of superoxide dismutase, peroxidase and catalase, increase contents of proline, soluble sugar and soluble protein, increase tissue relative water content and decrease water saturation deficit.It was concluded that salt-alkali stress inhibited the colonization of AM fungus, but the mycorrhiza still played a positive role in maintaining the normal growth of plants under salt-alkali stress.

Automated summary

This study investigated the effects of arbuscular mycorrhizal (AM) fungi on the growth and saline-alkaline tolerance of Potentilla anserina L. The results showed that inoculation with AM fungus increased chlorophyll content, decreased malondialdehyde content, and increased activities of antioxidant enzymes. AM fungus also regulated osmoregulation substances content and water status, leading to the maintenance of normal plant growth under salt-alkali stress.