Amplicon libraries of ITS1 genes

DNA was extracted within 24 hour using the MoBio PowerSoil DNA Isolation kit (Qiagen, Valencia, CA, USA). Nested PCR was used to amplify the fungal internal transcribed spacer 1 (ITS1) using barcoded-primers. PCR-amplified products were pooled and purified using the AxyPrep DNA Gel Extraction kit (Axygen, Tewksbury, MA, USA) according to the manufacturer’s instructions, then quantified with the dsDNA HS Assay (Invitrogen, Darmstadt, Germany) and used for library construction for Illumina sequencing with the LTP Library Preparation kit (KAPA Biosystems, Boston, MA, USA). Sequencing data were obtained with an Illumina Miseq platform (San Diego, CA, USA) using the 2*300 paired-end protocol.