Bio-control Lab, Directorate of Research, University of Horticultural Sciences, Bagalkot, Karnataka, India.
Department of Biotechnology and Crop Improvement, University of Horticultural Sciences, Bagalkot, Karnataka, India.
Sci Rep. 2019 Jul 12;9(1):10097. doi: 10.1038/s41598-019-46588-9.
Bacterial blight caused by Xanthomonas axonopodis pv. punicae is a major disease of pomegranate. Bacterial blight drastically reduces the yield and quality of fruits, which are critical for pomegranate production. Precise and early diagnosis of bacterial blight is crucial for active surveillance and effective management of the disease. Symptoms based disease diagnostic methods are labor-intensive, time-consuming and may not detect disease on asymptomatic plants. DNA-based disease diagnostics using polymerase chain reaction (PCR) are reliable, precise, accurate and quick. PCR coupled with agarose gel electrophoresis (PCR-AGE), PCR coupled with capillary electrophoresis (PCR-CE) and real-time PCR (qPCR) were applied for the early and accurate diagnosis of bacterial blight in pomegranate. PCR-CE and qPCR were capable of diagnosing bacterial blight 6 to 10 days before symptom appearance, with detection limits of 100 fg and 10 fg of bacterial DNA respectively. However, conventional PCR-AGE detected pathogen at the onset of disease symptoms with a detection limit of 10 pg of bacterial DNA. qPCR detected bacterial blight in orchards that did not show any disease symptoms. Our data demonstrate that qPCR is more sensitive than other PCR methods along with being reliable for early diagnosis.
由黄单胞菌引起的细菌性黑斑病是石榴的主要病害。细菌性黑斑病严重降低了果实的产量和质量，而果实对石榴生产至关重要。准确和早期诊断细菌性黑斑病对于主动监测和有效管理该病至关重要。基于症状的疾病诊断方法既劳动密集又耗时，并且可能无法检测无症状植物上的疾病。使用聚合酶链反应（PCR）的基于 DNA 的疾病诊断方法可靠、精确、准确且快速。PCR 与琼脂糖凝胶电泳（PCR-AGE）、PCR 与毛细管电泳（PCR-CE）和实时 PCR（qPCR）被用于石榴中细菌性黑斑病的早期和准确诊断。PCR-CE 和 qPCR 能够在症状出现前 6 至 10 天诊断细菌性黑斑病，检测限分别为 100 fg 和 10 fg 的细菌 DNA。然而，常规 PCR-AGE 在用 10 pg 细菌 DNA 检测病原体时开始出现疾病症状。qPCR 检测到了没有任何疾病症状的果园中的细菌性黑斑病。我们的数据表明，qPCR 比其他 PCR 方法更敏感，并且是早期诊断的可靠方法。
