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Summary of the Express Pest Risk Analysis for Hop stunt viroid na chmielu (Humulus lupulus)


Hop stunt viroid (HSVd) has broad host range but most of its infections are asymptomatic. Fortunately, so far viroid has not been reported in Poland. However, research carried out in Slovenia (one of the main hop producers in UE) showed that HSVd occurs in some tree plantations and hop fields (main host plant).

Rating of the likelihood of entry in PRA area: low (Most of propagation material is producted in Poland. Seedlings are imported from Germany, where viroid is not present. HSVd occurs in Japan, China, USA, but import from those area is insignificant.

Import of infected citrus is main way of entry. Most of plant waste is sent to landfill sites, where virioid poses no risk.

However spread from citrus to hops is asocciated with risk of the waste-related transmission.

It is important that viroid may be easily mechanically transmited between plants. High density planting also increase the risk of spread.

HSVd can be also transmitted by contaminated tools and machinery, clothing. Sanitary and phytosanitary measures must be complied with in full.

Cultivations of host plants need to be systematically monitored in case of viroid occurence.


  • Hop stunt viroid


  • Citrus sp.
  • Cucumis sativus
  • Humulus lupulus
  • Prunus armeniaca
  • Prunus domestica
  • Prunus persica
  • Pyrus communis
  • Vitis vinifera


Type File Size
Pest Risk Analysis Download 634,81kB

PRA Area

  • Poland