Comparison of three commercial DNA extraction kits for the enhancement of PCR assay sensitivity for Xanthomonas euvesicatoria pv. allii

Aim: The study was carried out to evaluate three commercial DNA extraction kits, Probe GS, FitoSorb and Sorb GMO, thus identifying the most suitable for isolating the phytopathogenic bacteria Xanthomonas euvesicatoria pv. allii. Materials and Methods: Onion seed samples were prepared which were inoculated with bacterial concentrations ranging from 101 to 107 CFU per ml. Real-time PCR was performed to determine the efficacy of the isolated DNA in enhancing the sensitivity of the assay. The DNA extracted by Probe GS had the best detectability, having been detected at the lowest concentration used in the study 101 × 3 CFU per ml. FitoSorb and Sorb GMO yielded DNA with a higher and similar limit of detection 103 × 3 CFU per ml. Furthermore, Probe GS had the lowest cycle at every concentration tested as compared to the other methods. Conclusion: Therefore, Probe GS proved to be the most optimized kit for the extraction of X. euvesicatoria pv. allii, hence enhanced degree of sensitivity for the assay. Impact and Significance of the Study: The findings generated in this study can be used by phytosanitary laboratories to develop highly rapid and accurate diagnostic protocols for X. euvesicatoria pv. allii. © 2021 The Society for Applied Microbiology