Calcareous impact on arbuscular mycorrhizal fungus development and on lipid peroxidation in monoxenic roots

► The study pointed out, for the first time, the CaCO3 negative effects on the arbuscular mycorrhizal symbiosis. ► CaCO3 impaired the main stages of Glomus irregulare life cycle but did not inhibit it completely. ► Root colonization reduction was confirmed by the AM fungal marker C16:1ω5 decrease. ► Oxidative stress was evaluated by fatty acid analysis, malondialdehyde formation and peroxidase assessment. ► AM symbiosis enhance the plant tolerance to CaCO3 by preventing lipid peroxidation.