Hormone concentrations in tobacco roots change during arbuscular mycorrhizal colonization with Glomus intraradices.

•  Phytohormones are known to play a pivotal role in various developmental processes in plants and in arbuscular-mycorrhizal (AM) fungal-host symbiosis. This study focuses on characterizing the changes in the concentrations of auxins, cytokinins and gibberellins in tobacco (Nicotiana tabacum) during the early stages of colonization by Glomus intraradices, using advanced analytical detection techniques. •  High-pressure liquid chromatography analysis followed by radioimmunoassay detection revealed that AM colonization induced the accumulation of specific zeatin riboside-like and isopentenyl adenosine-like compounds in both roots and shoots.