DETECTION AND IDENTIFICATION METHODS AND NEW TESTS AS USED AND DEVELOPED IN THE FRAMEWORK OF COST 873 FOR BACTERIA PATHOGENIC TO STONE FRUITS AND NUTS Pseudomonas syringae pathovars

SUMMARY Pseudomonas syringae is responsible for causing diseases on over 180 plant species including fruit trees, vegetable crops and flowers. Pathovars of main economic importance in Europe are the pvs syringae, morsprunorum, avii and persicae, causing bacterial canker on sweet and sour cherry, plum, peach and apricot as well as in wild cherry. In the framework of COST873 methods and techniques as developed and used in different laboratories for detection and identification have been tested and partly validated in several training schools. They are compiled in this contribution. The methods used for diagnosis and discrimination of pathovars include, among the others, the biochemical tests LOPAT and GATTa, the analysis for production of the phytotoxins coronatine and syringomycin and the siderophore yersiniabactin as well as a pathogenicity test. Molecular tests described concern PCR for phytotoxins, rep-PCR, including BOX, ERIC, REP and IS50, multilocus sequence typing (MLST) and the quite new melting profile PCR (PCR MP). All enable distinction of the pathogens and determination of homogeneous or heterogeneous groups within pathovars and pathovar’s races.