Formalisation of a method for detecting Xanthomonas (Xap and Xff) on bean seeds

Common bean blight caused by Xanthomonas axonopodis pv. phaseoli (Xap) and Xanthomonas fuscans subsp. fuscans (Xff) is one of the most devastating bacterial diseases of beans.

These bacteria can be present asymptomatically in plants and seeds, and spread worldwide mainly through seeds. In this context, it is essential to be able to detect these bacteria in seeds to limit the spread of the disease.

As part of its NRL mandate in Plant Health, GEVES has proposed a new method for detecting these non-quarantine regulated organisms (NQROs) on bean seeds. This method is an evolution of the ANSES MOA 030 method in which GEVES has integrated real-time TaqMan PCR (qPCR). This now official method is used for all official analyses for the detection of Xap and Xff in bean seeds.