Dark Septate Endophytes (DSE) Of The "Non-mycorrhizal Plants"

Arbuscular mycorrhizal fungi (AMF) can associate with more than 80% of the plants in the world to form Arbuscular mycorrhiza (AM).which is the most extensive range of host plants mycorrhizal fungi. Dark septate endophytes (DSE) are root endophytic fungi which has been concerned for the past twenty years. It also has a wide range of host plants and ecological distribution. This study selected "non-mycorrhizal plants" that cannot be easily formed mycorrhizals in nature from Gejiu, Yunnan, Lijiang, Kunming, Lancang, Huize in Yunnan as surveyed plants, and the natural infection status of AMF and DSE in the root of these plants was analyzed by morphological analysis, DSE colonized the plant roots was isolated and molecular identified; Finally Oxyria sinensis growing in the heavy metal mining and non mining area was collected, and the molecular diversity of fungi in the root was analyzed. The main results are as follows:(1) In the surveyed "non-mycorrhizal plant" (43 species and 192 individuals in total), about 118 samples in 31 species of plants had typical AMF colonization, whereas 168 samples in 41 species of plants had typical DSE colonization, AMF infection rate was 61.46%, the total infection rate of DSE was 87.50%. Among the all samples typically colonized by AMF and DSE, the infection intensity of AMF and DSE varied between 0.44%～10.56% and 0.56%-47.56%, respectively.(2) DSEs isolated from Gejiu, Kunming and Huize covered many fungal genera based on the molecular identification. Fungal strains from Gejiu were mainly Cladosporium and Chaetothyriales, the strains from Kunming were mainly Phialophora and Spirosphaera, and the strains from Huize were mainly Exophiala and Cyphellophora.(3) High-throughput sequencing was hired to explore the fungal diversity in the roots of Oxyria sinensis growing in mining and non mining area, It was found that the fungal abundance, diversity in the root of Oxyria sinensis between mining and non mining area different greatly:the fungal species in the root of the mining area is richer than that of in the non mining area, and the fungal composition of in the mining area varied greatly, while the fungal composition of in the non mining area is relatively eveness.These results demonstrated that DSE was generally colonized in the "non-mycorrhizal plants", and had a wider host plant range than AMF. DSEs from the "non-mycorrhizal plants" in different environments varied greatly. For the same plant (Oxyria sinensis), DSEs in the roots growing in the mining and non mining areas are also different, and the differences between the varied samples in the mining area is larger than that of in the non mining area.