Using native plants to evaluate the effect of arbuscular mycorrhizal fungi on revegetation of iron tailings in grasslands

A pot experiment was conducted to evaluate native plant species associated with exogenous AMF for their suitability in the revegetation of iron mine tailings of Inner Mongolia grassland. Agropyron cristatum (L.) Gaertn. and Elymus dahuricus Turcz. associated with AMF, Glomus mosseae, or Glomus versiforme, were grown on iron mine tailings to assess the mycorrhizal effects on plant growth, mineral nutrition uptake, C:N:P stoichiometry, and heavy metals uptake. The symbiotic associations were successfully established between exogenous AMF and two native plants, and root colonization rates of G. versiforme were significantly (P < 0.05) higher than those of G. mosseae. G. versiforme was more effective than G. mosseae in promoting plant growth by significantly (P < 0.05) increasing the concentrations of N, P, and K and decreasing the ratios of C:N:P. The shoot and root dry weights of A. cristatum and E. dahuricus were increased by 51-103 %. The N, P, and K concentrations of shoots and roots of two plants were increased by 18-236 %. Inoculation with AMF also significantly (P < 0.05) decreased concentrations of heavy metals in the shoots and increased those in the roots, indicating that AMF could confer some degree of heavy metal tolerance to plants. The results indicated that plant inoculation with G. versiforme was more suitable than inoculation with G. mosseae for the revegetation of iron mine tailings. The experiment provided evidence for the potential use of local plant species in combination with exogenous AMF for ecological restoration of metalliferous tailings in arid and semi-arid grassland.