Dispersal of quarantine pests from businesses receiving potatoes or vegetables, both washed and unwashed
Report no: 2018: 15
Quarantine pests may be dispersed with organic waste, wastewater or sludge from packing plants that handle domestic and imported potatoes and vegetables. The effectiveness of risk reduction options varies.
This is the key message in a risk assessment that the Norwegian Scientific Committee on Food and Environment, VKM, has conducted on the request of The Norwegian Food Safety Authority (NFSA).
The crops relevant for the assessment are potatoes, bulb, carrots, onions and other root vegetables that are susceptible to damage from quarantine pests. A quarantine pest is a pest of potential economic importance to the area endangered thereby and not yet present there, or present but not widely distributed and being officially controlled.
Viruses, bacterias, fungus and nematodes
VKM has identified in total 13 plant pathogenic viruses, five plant pathogenic bacteria and phytoplasmas, five plant pathogenic fungi, six plant parasitic nematodes and four plant parasitic insects are considered to have potential for dispersal with waste from packing plants.
The entry of two plant pathogenic bacteria is very likely as the ring rot bacterium Clavibacter michiganensis ssp. Sepedonicus is present in Norway, while there are regular outbreaks of the brown rot bacterium Ralstonia solanacearumin countries exporting potatoes to Norway.
The entry of the onion white rot fungus Stromatinia cepivora into packing plants is very likely due to its domestic distribution and its distribution in countries exporting onions to Norway.
The entry of the potato wart fungus Synchytrium endobioticum with domestic potato is unlikely, but the entry of the pest with imported potato is moderately likely, due to its distribution in countries exporting potato to Norway.
The entry of the stem and bulb eelworm Ditylenchus dipsaci and the potato rot nematode D. destructor is moderately likely.
The entry of yellow potato cyst nematode Globodera rostochiensis is very likely. The entry of the white potato cyst nematode G. pallida is moderately likely for imported potato and very likely for imported potato.
As the two nematodes Meloidogyne chitwoodi and M. fallax are absent from Norway, the probability of entry into packing plants is unlikely for domestic crops and moderately likely for imported crops.
Risk reduction options
VKM has identified and assessed risk reduction options. The effectiveness of the risk reduction option varies.
Safe deposition of damaged or rotten potato and root vegetables reduce the risk of spread of quarantine pest to agricultural land. Another risk reduction option is to rinse the waste water used for washing of potatoes and root vegetables.
Passing the waste water through municipal treatment plant has high effectiveness and feasibility, while further filtration or UV-treatment has low effectiveness and low feasibility.
Heat treatment of organic waste has high effectiveness and feasibility for most pests, but the effectiveness and feasibility are considered low to medium for Synchytrium endobioticum, Stromatinia cepivora, Globodera spp. and Meloidogyne spp.