title: Root70_VC1.fastq
design: Metagenomic DNA was extracted using DNeasy PowerSoil Pro DNA Kit (Qiagen, USA). 16S rRNA gene was amplified using 341F and 805R primers, targeting V3-V4 variable regions and 2X sparQ HiFi PCR master Mix (QuantaBio, USA). The amplification condition included an initial denaturation step 2 min at 98 C, followed by 30 cycles of 98C for 20 s, 60C for 30 s, and 72C for 60 s, followed by a single step final extension step at 72C for 1 min. Subsequently, 16S amplicons were purified using sparQ Puremag Beads (QuantaBio, USA) and indexed using 2.5 l of each Nextera XT index primer in a 50 l PCR reaction, followed by 8-10 cycles of PCR condition above. The final PCR products were cleaned, pooled and diluted to final loading concentration at 4 pM. Cluster generation and 250-bp paired-end read sequencing were performed on an Illumina MiSeq at Omics Sciences and Bioinformatics Center (Chulalongkorn University, Bangkok, Thailand).