Tobacco Rattle Virus
Tobacco Rattle Virus (TRV) is one of the causes of the appearance of unsightly brown markings and rings on affected tubers – known as spraing, which can often lead to ware crops becoming unsellable.
Common Signs and Symptoms of Tobacco Rattle Virus
The main symptoms of TRV in tubers are brown, cork-like, spots and arcs in the flesh.
Symptoms of spraing can also be spotted on the plants with V shaped markings on the haulms, although these may vary in colour (yellow to green) depending on variety.
Common Causes and Conditions of Tobacco Rattle Virus
TRV is soil-borne, being transmitted by trichodorid nematodes, and occurs mainly in lighter, sandy soils such as those found around the Norfolk, West Midlands and York Vale areas of Great Britain.
Vulnerable / Immune Varieties
Potato varieties which have a good resistance TRV include Caesar, Fianna, Hermes, Lady Rosetta, Romano and Symfonia
Controlling Tobacco Rattle Virus
Once established at a site, TRV and its vector nematodes are notoriously very difficult to control or eradicate.
Cultural and Methods:
Avoid over irrigating – the nematodes which cause TRV are commonly more active in wet soil.
TRV can often be hosted in weeds, so practicing good weed control will reduce the virus levels in the trichodorid nematode population.
Nematicides and fumigants are available in the UK to successfully control tobacco rattle virus, but they are both expensive and toxic.