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Journal of Integrative Agriculture  2020, Vol. 19 Issue (4): 898-905    DOI: 10.1016/S2095-3119(19)62881-9
Special Focus: Bleeding canker of pear-An emerging devastating disease Advanced Online Publication | Current Issue | Archive | Adv Search |
Real-time PCR assay for detection of Dickeya fangzhongdai causing bleeding canker of pear disease in China
TIAN Yan-li1, ZHAO Yu-qiang2, CHEN Bao-hui1, CHEN Shuo1, ZENG Rong1, HU Bai-shi1, LI Xiang
1 College of Plant Protection and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing Agricultural University, Nanjing 210095, P.R.China
2 Institute of Botany, Jiangsu Province and Chinese Academy of Sciences (Nanjing Botanical Garden Mem. Sun Yat-Sen)/Jiangsu Key Laboratory for the Research and Utilization of Plant Resources, Nanjing 210014, P.R.China
3 Charlottetown Laboratory, Canadian Food Inspection Agency, Charlottetown, PE C1A5T1, Canada
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Bleeding canker, caused by Dickeya fangzhongdai, is a devastating disease of pear in China.  The bacterium causes cankers, branch die-back, and eventually kills pear trees.  The typical sign of bleeding canker infection is a rusty-brown bacterial ooze that exudes down from cankers onto branches or trunks.  However, early symptoms and signs are inconspicuous, which makes effective disease management difficult.  Detection and identification of D. fangzhongdai are time-consuming and difficult because no rapid method exists to date.  In this study, a TaqMan real-time PCR assay was developed for D. fangzhongdai based on an elongation factor G (fusA) gene.  The real-time PCR assay detected 0.2 pg µL–1 DNA and 1×103 cfu mL–1 of D. fangzhongdai.  Based on this assay, bleeding canker on asymptomatic pear trees can be diagnosed as early as 5 days after infection.  The real-time PCR assay can facilitate disease management by providing early and accurate diagnosis of the bleeding canker disease of pear.
Keywords:  molecular assay        pear bleeding canker        detection  
Received: 28 October 2019   Accepted: 04 March 2020
Fund: This study was supported by the National Key Scientific and Technological Projects of China for pear diseases (2018B01005).
Corresponding Authors:  Correspondence HU Bai-shi, E-mail:; LI Xiang, E-mail:    

Cite this article: 

TIAN Yan-li, ZHAO Yu-qiang, CHEN Bao-hui, CHEN Shuo, ZENG Rong, HU Bai-shi, LI Xiang. 2020. Real-time PCR assay for detection of Dickeya fangzhongdai causing bleeding canker of pear disease in China. Journal of Integrative Agriculture, 19(4): 898-905.

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