Suillus sp.: A Potential Ectomycorrhizal Species for Ecological Restoration in Da Qin Mountain Regions of Inner Mongolia

The vegetation of Da Qin Mountain, which is located in Yellow River upper basin, is one of the most threatened ecosystems in north-western of Inner Mongolia of China, with 5% or less of their original stand presently existing. To assess the mycorrhizal status in this degraded barren region, root of native species, most belong to the secondary growth species,were collected throughout the year under different stands. Major host genus are Pinus, Larix,Populus, Betula, Tilia, Quercus, and Ostryopsis. Major fungal genus are Amanita, Boletus,Cenococcum, Hebeloma, Lactarius, Paxillus, Rhizopogon, Russula, Scleroderma, and Suillus. However the most frequent species are Suillus sp. and Cenococcum geophilum.More than 40 ectomycorrhizal strains were isolated from mycorrhizal tissue and rarely from sporophore. The selection of the most efficient ectomycorrhizal strains has been carried out in laboratory, nursery and after field transplantation. The assessment of seedling growth showed that Suillus sp. is a superlative performance strain for ectomycorrhizal controlling application with the quality of better mycelia propagation feature, better capacity of infection,competition and adaptation. The total seedling height increased to 80.3% in nursery. The survival rate increased to 26% and total stem height increased to 139.5% at the end of third year growth season in the field transplantation. Therefore the controlling ectomycorrhizal technique with the fungal strain of Suillus sp. has shown a great potential for vegetation reconstruction in Da Qin Mountain regions of Inner Mongolia.