First report of Phytophthora chrysanthemi in Germany
The NPPO of Germany recently informed the EPPO Secretariat of the first report of Phytophthora chrysanthemi on its territory. P. chrysanthemi was originally described in Japan from chrysanthemums showing stem and root rot (EPPO RS 2015/169) and very limited information is available about its biology, host range, and geographical distribution. In Germany, P. chrysanthemi was first found in August 2015 in a production site (glasshouse) of chrysanthemum cut flowers located in Hesse. In this glasshouse, one lot of chrysanthemum plants (Chrysanthemum indicum hybrid – 200 plants) was displaying wilted leaves, fewer roots and discolorations at the stem bases. All the other plant species grown in the nursery looked healthy. Six symptomatic plants were sent to a laboratory in Hesse and to JKI for diagnosis. Morphological and molecular methods confirmed the identity of the pathogen. In August 2016, a second lot of chrysanthemum potted plants was found showing the same symptoms. Diagnostic analysis is underway and the results are still pending. It is suspected that the pathogen has been introduced with infected plant material but tracing-back studies are ongoing to determine the possible origin of this outbreak. All infested plants have already been destroyed. The production site will be placed under official control.
The pest status of Phytophthora chrysanthemi in Germany is officially declared as: Transient, only at one location, under eradication.
NPPO of Germany (2016-11).