Effects of sanitation processes on survival of Synchytrium endobioticum and Globodera rostochiensis

The two quarantine pests Synchytrium endobioticum,the causal agent of potato wart disease andGlobodera rostochiensis, the yellow potato cyst nematodeare currently present in Germany.Winter sporangiaof Synchytrium endobioticum and cysts of Globoderarostochiensis can be spread with waste from potatoprocessing industries, if infected tubers are processed.The German Biowaste Ordinance prescribes sanitationof organic waste before it can be used on arable land asfertilizer or filling material. Sanitation parameters prescribedby the German Biowaste Ordinance includecomposting for 7 days at 65°C or 14 days at 55°C orpasteurisation for 60 min at 70°C. The effect of compostingand pasteurisation processes on winter sporangiaof Synchytrium endobioticum and cysts ofGlobodera rostochiensis was tested with varying timetemperaturerelations. Cysts of Globodera rostochiensiswere killed by composting for 7 days at 50–55°C and by pasteurisation for 30 min at 70°C. In contrast, viablewinter sporangia of Synchytrium endobioticum couldbe extracted from sample material after composting for70 days at 30–45°C, composting for 21 days at 50–55°Cand after composting for 12 days at 60–65°C. Likewiseviable winter sporangia could be extracted after pasteurisationfor 90 min at 70°C and heating in a water bath at80°C and in a dry oven at 90°C for 8 h. The parametersprescribed in the German Biowaste Ordinance are sufficientto kill cysts of Globodera rostochiensis but notsufficient to kill winter sporangia of Synchytrium endobioticumin organic waste.