M. M. Lou, State Key Laboratory of Rice Biology and Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China;
G. L. Jin, Institute of Bioinformatics, Zhejiang University, Hangzhou 310029, China; and
W. X. Tian,
G. Q. Zhang,
X. Y. Fan,
B. Zhu, and
G. L. Xie, State Key Laboratory of Rice Biology and Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Ministry of Agriculture, Institute of Biotechnology, Zhejiang University
Go to article:
Accepted for publication 15 May 2011.
Enterobacter mori, the causal agent of bacterial wilt in mulberry, is becoming a serious disease in mulberry orchards in China. Because no effective control strategy has been devised for this disease, the reliable screening of mulberry material for latent infection became necessary. Hence, a fast polymerase chain reaction (PCR) assay for the detection of E. mori was developed in this study. The primers were designed within regions of the RNA polymerase β-subunit (rpoB) gene. The method is fast and simple and showed 100% sensitivity (no false negatives) and 100% specificity (no false positives), which was tested with 4 representative E. mori strains, 9 Enterobacter type strains, 2 strains of the other major mulberry bacterial pathogens (Ralstonia solanacearum and Pseudomonas syringae pv. mori) in China, 7 strains of other plant-associated pathogens, and 50 unidentified epiphytic bacterial isolates from mulberry plants. The real-time PCR assays reliably detected the DNA at at least 10 fg/μl and the bacterial cells at 102 CFU/ml from mulberry shoots and roots suspension. The strong positive reaction in testing of all symptomatic plants (with 100% positive) and parts of asymptomatic latent infected plant samples (with 36.4% positive) provided proof that this method is reliable and sensitive and suitable for screening plant material with latent infections of E. mori.
© 2011 The American Phytopathological Society