Tomato yellow leaf curl virus: declared pest

Page last updated: Thursday, 11 July 2019 - 5:11pm

Tomato yellow leaf curl virus (TYLCV) is a very damaging virus disease of tomato crops in tropical and warm temperate regions of the world, causing losses of up to 100%. This virus is not known to occur in Western Australia. Early detection and reporting of TYLCV will help protect the Western Australian tomato industry.

Plants affected

The main host of Tomato yellow leaf curl virus (TYLCV) is tomato, but the disease can also affect French bean, chilli, eggplant and capsicum. Some weeds and ornamental plants such as lisianthus and petunias can carry the virus and may not show obvious symptoms.

What to look for 

Null
Tomato plants infected with Tomato yellow leaf curl virus are stunted and malformed (Photo by John Thomas)
  • Tomato plants infected early are severely stunted and will not produce fruit.
  • Leaflets are small and yellowed with edges that curl upwards.
  • Flowers either do not develop or fall off.
    Null
    Leaflets are small and yellowed with edges that curl upwards (Photo by John Thomas)
  • When older plants are infected, fruit that is already forming ripens normally, but no new fruit is formed after the infection.
  • TYLCV can be confused with several other conditions such as tomato big bud, herbicide damage and phosphate or magnesium deficiency.  
  • In infected beans, leaves thicken and curl upwards, and abnormal side shoots form.

Survival and spread 

  • TYLCV is spread by the insect silverleaf whitefly (Bemisia tabaci B biotype).
  • Silverleaf whiteflies pick up the virus by feeding on infected host plants. The whiteflies then spread the virus to healthy plants which show the symptoms 10 to 21 days later.
  • Silverleaf whiteflies are common in Carnarvon and feed on many types of plants.
  • TYLCV is not seed-borne or spread by handling or pruning.
  • Infected weeds such as blackberry nightshade and Malva parviflora can act as reservoirs of the virus.

Damage

TYLCV can completely destroy tomato crops and causes disease in French bean, chilli, capsicum and some ornamental plants.

Status in Western Australia 

Tomato yellow leaf curl virus (TYLCV) is considered absent from Western Australia and is a quarantine pest. It is a prohibited organism under section 12 of the Biosecurity and Agriculture Management Act 2007.

Western Australia's Pest Freedom for TYLCV is supported by general and specific surveillance, specific import requirements to prevent its entry, and legal requirements to report any occurrences of the pest.

Report suspect disease

It is important that any suspect disease occurrence is reported. Early detection and eradication will help protect Western Australian potato growers. Please make a report using MyPestGuide or contact the Pest and Disease Information Service (PaDIS) to report this pest.

Report your observations using theMyPestGuide Reporter  app or online at mypestguide.agric.wa.gov.au.

Contact information

Pest and Disease Information Service (PaDIS)
+61 (0)8 9368 3080