Identification of Erwina stewartii Minimize

April 2004. A request from Vietnam where to obtain primers to detect E stewartii.

Sampling rates and procedures for conducting ELISA testing for E stewartii are given in the International Seed Federation publication - Pataky and Ikin (2003) PEST RISK ANALYSIS - The risk of introducing Erwinia stewartii in maize seed.

Two sets of sequences for primers for Pantoea stewartii (rRNA ITS region) are given in Laboratory Guide to Identification of Plant Pathogenic Bacteria (3rd Edition) edited by Schaad, Jones and Chun (2001) American Phytopathological Society ISBN 0-89054-263-5. It is unlikely that there are companies who stock these so the sequences would need to be supplied. Whether they are specific for Pantoea stewartii subsp. stewartii or if they also react with Pantoea stewartii subsp. indologenes, which causes a disease of some grasses in Asia, was not kknown. The former was called Erwinia stewartii; the latter was part of Erwinia herbicola.

See Coplin et al. 2002. Identification of Pantoea stewartii ssp. stewartii by PCR and strain differentiation by PFGE. Plant Dis. 86:304-311.

Another member supplied the sequences: Forward primer: TGC GAA GCG AGG ACA CAC GTA Reverse primer: GAC ACC TTT CAC CTG TCA CCA A. The can be synthesized by a local university or by a commercial company, e.g., Integrated DNA technology. They can be found on the web at