Development and validation of innovative diagnostic tools for the detection of fire blight (Erwinia amylovora) (ERWINDECT)

• Research unit: FOAG
• Project number: 07.14_1

Short description (English)

Erwinia amylovora, causal agent of fire blight, is a quarantine bacterium in Europe. Rapid and on-site diagnosis is critical for optimal implementation of phytosanitary control measures. Different diagnostic screening tests for a rapid diagnosis of E. amylovora are commercially available and new methods have recently been published. However, these have not yet been validated for phytosanitary applications and require ring-testing for validation. Validation tests should be performed including those protocols which were recently revised by the European Plant Protection Organization (EPPO/OEPP), thus supporting the preparation of the new protocol for the Food and Agriculture Organization of the United Nations (FAO/IPPC). Usually these tests are designed for application in laboratory settings and they may not be adequate for on-site diagnostics. Thus, innovative detection methods should be developed specifically suitable for on-site diagnosis. New diagnostic tests (e.g., commercial PCR methods, immunological tests) have been developed since the last European validation trials. The application of these tests for laboratory and on-site use requires validation in ring-trials. Innovative tests suited for on-site applications need to be developed in case the existing tools are insufficient. Recent advances with other diseases using immunological and on-site PCR tools could be used as models for developing similar tools for fire blight. Determination of asymptomatic infection is newly mandated by EU regulations, but currently no appropriate protocols are available. Sampling for asymptomatic infections is particularly difficult, since testing of a high number of randomised samples is necessary and the isolation of latent bacteria from woody tissues is challenging. The long-term control of fire blight requires eradication of inoculum reservoirs. Methods to source-track E. amylovora considering sampling protocols and molecular identification to the strain level should be developed.

Project aims (English)

1) Validate several recently developed diagnostic tests with international ring-tests

2) Apply pathogen genomics for developing new diagnostic techniques

3) Determine the utility of new diagnostic techniques for detection of latent infections and flower monitoring

Transfer and application (English)

Swiss pome fruit producers, cantonal plant inspectors, diagnostic laboratories, phytosanitary inspectors, environmental interest groups, international research consortia