Dickeya: The North American potato threat

The main bacteria causing potato blackleg and tuber soft rot are Pectobacterium atrosepticum, P. carotovorum subsp. carotovorum, and Dickeya spp., all formerly belonging to the genus Erwinia. Dickeya and Pectobacterium affect a number of host species including potato. These bacteria characteristically produce a range of cell-wall-degrading enzymes that macerate plant tissues on which they nourish. In 2015, a new blackleg pathogen emerged in the Eastern United States that caused significant losses in some potato producing areas. The pathogen was confirmed as Dickeya dianthicola, and there are concerns the disease could spread to Canada. That’s because Dickeya can spread over long distances, and across national borders, in infected vegetative propagating material. Yield reductions of 20 to 25 per cent or higher resulting from Dickeya infections have been reported on various potato cultivars in Europe and the Middle East. More