sequencing of fungal ITS region
Microbial DNA was extracted according to the instructions of NucleoSpin Soil Kit (Macherey-Nagel, Germany). The fungal ITS region were amplified using the primer pairs  ITS3-2024F(GCATCGATGAAGAACGCAGC)/ ITS4-2409R (TCCTCCGCTTATTGATATGC). PCR was performed using Phusion High-Fidelity PCR Master Mix (New England Biolabs, Ipswich, MA, USA). PCR cycling condition was as follows: 3 min denaturation at 95 C; 30 cycles of denaturation at 95 C for 45 s, annealing at 56 C for 45 s, elongation at 72C for 45 s; and final extension at 72 C for 10 min. The PCR products were used to construct libraries used for sequencing on MiSeq platform, according to the manufacturer's recommendations.