Fig. 2

Displays the ability of the three primer pairs to amplify the gyrA gene for seven Bacillus strains. A The position of gyrA amplicons was obtained by primer pairs gyrA1, gyrA2 and gyrA3. B PCR amplification of seven Bacillus strains using three gyrA primer pairs. The orange square indicates that the target gene of gyrA was amplified by the indicated primer pair, and the white square indicates that it was not. The phylogenetic tree was constructed based on the complete 16S rRNA (1358 bp) (Additional file 2: Dataset S3) by using the Neighbor-Joining method in MEGA 5.05 software. The reliability of clades was tested by the 1000 bootstrap replications. C Display of the results of the computer simulation amplification ability of the three gyrA primer pairs using the gyrA sequence database. The white columns represent the number of sequences in the database that were matched by the primers, while the grey columns represent the number of Bacillus species identified by the primer pairs (Additional file 2: Table S6). The gyrA sequences in database were downloaded from the NCBI genome database (Additional file 2: Table S3)