Rhizosphere bacterial community 16S rDNA sequencing
PCR reactions were carried out with Phusion  High-Fidelity PCR Master Mix (New England Biolabs). Then the PCR products were electrophoresed to obtain bright main strip between 400 450 bp. Mixture PCR products with equidensity ratios for each sample were purified with Qiagen Gel Extraction Kit (Qiagen, Germany). Sequencing libraries were generated using TruSeq  DNA PCR-Free Sample Preparation Kit (Illumina, USA) following manufacturer's recommendation and index codes were added