metagenome of microbial communities: rhizosphere
The 16S rRNA gene V4 region PCR primers 515/806 with barcode on the forward primer were used. PCR using the HotStarTaq Plus Master Mix Kit(Qiagen, USA) was run under the following conditions: 94C for 3 minutes, 30 cycles of 94C for 30 seconds, 53C for 40 seconds and 72C for 1 minute, final elongation at 72C for 5 minutes. PCR products are checked in 2% agarose gel. Multiple samples are pooled together and purified using calibrated Ampure XP beads.