Potato cyst nematode


​​ Potato cyst nematode


Potato cyst nemotade

(Globodera species)

Exotic to Australia (White potato cyst nematode), or under
management (Golden potato cyst nematode)

Life form: Nematode
Origin: South America
Distribution: Europe, South and North America, Asia, Africa
and New Zealand
Features: Leaf wilting and discoloration, root cysts and reduced
root system, yield reduction and smaller potatoes, dwarfing of
plant and early senescence
Pathways: Movements of cysts via wind, rain, water, soil,
vehicles, plant material
At risk: Solanum species including potato, tomato and aubergine


Potato cyst nematodes are microscopic round worms that feed on the roots of potato, tomato, aubergine and other plants from the family of the Solanaceae (night shade plants). It is a serious pest to potatoes that can cause complete crop failure if not controlled. It has the potential to cause significant damage to the Australian potato industry through crop losses and the loss of export markets.

There are two types of potato cyst nematode:

  • white or pale potato cyst nematode (Globodera pallida)
  • yellow or golden potato cyst nematode (Globodera rostochiensis).

Potato cyst nematodes live and feed on the roots of potato and other hosts causing significant damage to their root systems. Significant damage below the ground can be done before symptoms are even visible above ground.

The soil-borne pest is spread by wind, rain, water, transport of infected soil sticking to seeds, animals, equipment, clothing and plants. Potato cyst nematodes can survive as cysts in the soil for up to 20 years in the absence of host species.

Occurring in many countries worldwide, the pest has been introduced into Europe, North America, Central America and Carribean, Asia, Africa and New Zealand. Between 1986 and 1989, golden potato cyst nematodes was found in Western Australia in Australia. A strict eradication program was undertaken and after continuous monitoring, there have been no detections since 1989. Victoria detected golden potato cyst nematodes in 1991, and it is contained to three quarantined areas there. However, only one strain of golden potato cyst nematodes, the Ro1 strain, has ever been confirmed in Australia.

How to identify Potato cyst nematode

Everyone needs to keep an eye out for potato cyst nematodes.

The nematodes are very small, less than 1mm in size and the cysts are similar size to a pin head (0.5mm). The male has a typical worm-like body, while the female becomes almost spherical after mating and appears as a cyst on root surfaces.  Both males and females are endoparasitic, which means they feed within roots. Potato cyst nematode juveniles hatch from the cysts which can contain up to 500 eggs. Once the juveniles hatch, they move between the soil particles and invade potato roots just behind the root tip. They feed on the plant root cells causing them to become very large and eventually rupture.

Cysts on potato roots caused from mature and immature potato cyst nematodes (under high magnification). Source: DAFWA
Close-up view of roots of potato plants covered in mature and immature cysts. The round cysts vary in colour from yellow to red.
Infested roots under high magnification from potato nematode cysts. Source: USDA
Close-up view of roots of potato plants covered in mature and immature cysts. The round cysts vary in colour from yellow to red.
Potato cyst nematodes causing a stunted patch of potato plants which are surrounded by a healthy crop.
A healthy crop of potato plant which has a section within it that is stunted from potato cysts nematodes. Evidence can be seen above ground from the pest as it has reduced the growth of the leaves.



Regulations on importation of tubers and items that can contain soil are designed to prevent this pest from entering Australia.

If you work around imported goods you need to ensure all goods and associated packaging and machinery meet the specific import conditions.

Growers and home gardeners

Check your plants or crops for root damage or cysts. Cysts can be visible with the naked eye.

If potato cyst nematodes became established in Australia it would have an appetite for:

  • potatoes
  • tomatoes
  • aubergines
  • roots of solanaceaous weeds.

Keep Potato cyst nematode out of Australia

All Australians and international tourists have a role to keep out exotic pests and diseases.

Australia remains free of this exotic pest, except for Golden PCN in three quarantined areas in Victoria. We need your help to keep it this way.

Check what you can and cannot bring into Australia, whether you are a:

We love our spuds

Potato cyst nematodes will affect our potato industry. Let’s work together to keep it out.

Import restrictions and biosecurity measures

Some items, by law, are subject to certain import conditions to be allowed into Australia. Please check the Biosecurity Import Condition System (BICON).

Be aware of any potato cyst nematode biosecurity measures that may be in place for incoming goods and conveyances. Industry advice notices are reviewed regularly and could change.

Secure any suspect specimens

Remember the pest can spread easily via the movement of contaminated soil, so be careful not to increase the risk of spreading the pest. Take a photo, record the location and get it checked by an expert.

Report detections of exotic pests

Any detections of potato cyst nematode must be reported to the authorities.

Import community

If you receive or work around goods imported from overseas, including mail, you need to be vigilant to potato cyst nematode and other exotic pests. If you see an unusual pest, secure the goods to limit the movement of the pest and immediately report it to the department's SEE. SECURE. REPORT. Hotline on 1800 798 636 or by using the online form.

Growers and home gardeners

If you see the potato cyst nematode or anything unusual, report it to the Exotic Plant Pest Hotline on 1800 084 881. This will put you in touch with the department of primary industries or agriculture in your state or territory.

When reporting your concern, you will be given advice on handling the specimen and what to do next until an officer can investigate.

Additional information

Last reviewed: 4 February 2020
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