PCR-based Assay for the Detection of Xanthomonas campestris pv. mangiferaeindicae Causing Bacterial Black Spot in Mango.

[Objective] This study aimed to develop a PCR assay for detecting Xanthomonas campestris pv. mangiferaeindicae (Xcm) in culture and in planta. [Method] Primers (XcmHF and XcmHR) were designed based on the partial sequence of hrpB gene from xanthomonads to develop a PCR assay for Xcm. Furthermore, specificity and sensitivity of the primer pairs were analyzed in detection of genomic DNA and cell from Xcm. [Result] Amplication was positive only with genomic DNA from positive control ATCC11637 and 12 Xcm strains; no PCR products were amplified with genomic DNA from ten other xanthomonads and seven other bacterial species. The sensitivity of detection was 2.4 pg/μl genomic DNA, and 1.8 × 104 CFU/ml cells. The primers also worked well for pathogen detection in direct PCR assays of Xcm colonies grown on liquid medium and in PCR assays of total DNA from leaf, branch and fruit lesions. [Conclusion] A PCR assay was successfully established for rapid detection of Xcm in culture and in planta. [ABSTRACT FROM AUTHOR]