the metageome of cowpea rhizosphere
The libraries were prepared using Nextera DNA Flex library preparation kit (Illumina) following the manufacturer's user guide. The initial concentration of DNA was evaluated (Table 1) using the Qubit dsDNA HS Assay Kit (Life Technologies). Because of low DNA concentration Sample1 library preparation was poor in first attempt. In order to get the enough DNA for library preparation whole genome amplification was carried out for Sample1 by using REPLI-g Midi kit (Qiagen). The linear amplified DNA was cleaned using the DNA Clean & Concentrator-columns (Zymo Research) and concentration was again evaluated (Table 1) using the Qubit dsDNA HS Assay Kit (Life Technologies). 6-50 ng DNA was used to prepare the libraries. The samples underwent the simultaneous fragmentation and addition of adapter sequences. These adapters are utilized during a limited-cycle (6 cycles) PCR in which unique indices were added to the sample. Following the library preparation, the final concentration of the libraries (Table 1) were measured using the Qubit dsDNA HS Assay Kit (Life Technologies), and the average library size (Table 1) was determined using the Agilent 2100 Bioanalyzer (Agilent Technologies). The libraries were then pooled in equimolar ratios of 0.7nM, and sequenced paired end for 300 cycles using the NovaSeq 6000 system (Illumina).