Webster John, Kehoe Monica A, Nogarotto Elisse, Falconer Linda, Donovan Nerida Jane, Chapman Toni A
NSW Department of Primary Industries, Elizabeth Macarthur Agricultural Institute, Menangle, NSW 2568, Australia.
DPIRD Diagnostics and Laboratory Service, Department of Primary Industries and Regional Development, South Perth, WA 6151, Australia.
Microorganisms. 2022 Jun 2;10(6):1153. doi: 10.3390/microorganisms10061153.
The ability to swiftly respond to pathogen incursions relies heavily on fast and accurate diagnostics. Current published assays for citrus bacterial canker do not target pv. , the causative agent, with high specificity when testing Australian samples. While the current diagnostics are useful in countries where canker is endemic, the detection of canker in Australia requires an emergency response. Close relatives to pv. found in Australia may generate false positives with the current recommended diagnostic assays. Therefore, we developed a more specific detection tool for citrus bacterial canker to provide greater diagnostic confidence for surveillance and eradication efforts. We used genomic comparisons of 161 Xanthomonad genomes and identified and confirmed genomic regions specific for pv. by performing local alignments of unique regions to reference genomes. We then developed loop-mediated isothermal amplification primers and validated them against a panel of 190 isolates to confirm specificity. Our diagnostic assay showed 100% corroboration with the concurrently developed multiplex primers and represents an improved diagnostic method capable of effective citrus bacterial canker identification.
迅速应对病原体入侵的能力在很大程度上依赖于快速准确的诊断。目前已发表的柑橘溃疡病检测方法在检测澳大利亚样本时，对致病病原体柑橘溃疡病菌（Xanthomonas citri pv. citri）的靶向特异性不高。虽然目前的诊断方法在溃疡病流行的国家很有用，但在澳大利亚检测溃疡病需要紧急应对措施。在澳大利亚发现的与柑橘溃疡病菌亲缘关系较近的病菌，可能会导致目前推荐的诊断检测出现假阳性结果。因此，我们开发了一种针对柑橘溃疡病更具特异性的检测工具，以便在监测和根除工作中提供更高的诊断可信度。我们对161个黄单胞菌基因组进行了基因组比较，并通过将独特区域与参考基因组进行局部比对，鉴定并确认了柑橘溃疡病菌特有的基因组区域。然后，我们开发了环介导等温扩增引物，并针对一组190个分离株进行了验证以确认其特异性。我们的诊断检测方法与同时开发的多重引物显示出100%的一致性，代表了一种能够有效鉴定柑橘溃疡病的改进诊断方法。
