The greater effectiveness of Glomus mosseae and Glomus intraradices in improving productivity, oil content and tolerance of salt-stressed menthol mint (Mentha arvensis)

BACKGROUND Mentha arvensis is cultivated in large parts of the world for its menthol-rich essential oil. The study investigates the potential of four mycorrhizal fungi, viz. Glomus mosseae (Gm), Glomus aggregatum (Ga), Glomus fasciculatum (Gf) and Glomus intraradices (Gi) in alleviating NaCl-induced salt stress in Mentha arvensis cv. Kosi and establishes the specificity of interaction between different mycorrhizal species and their effectiveness in mitigating salt stress in Mentha arvensis. Mycorrhizal and non-mycorrhizal Mentha plants were subjected to NaCl-induced salinity. RESULTS Among the four Glomus species, Gm and Gi reduced salt-induced herb yield losses: a loss of 27.53% and 25.58% respectively under salt stress in comparison to 51.00% in non-mycorrhizal M. arvensis salt-stressed plants. Gm- and Gi-inoculated plants also recorded higher leaf:stem ratio, oil content, and oil yield and menthol concentration in essential oil under both saline and non-saline conditions. CONCLUSION Better performance in terms of herb yield, and oil content and yield was observed in Gi- and Gm-inoculated M.arvensis plants, suggesting the capability of Gi and Gm in protecting plants from the detrimental effects of salt stress; beneficial effects of arbuscular mycorrhizal fungi, however, may vary with host and environment. (c) 2012 Society of Chemical Industry