June pest of the month: tospovirus
26 June 2024
Tospovirus is a species of plant virus. There are two types of this virus, including:
- tomato spotted wild virus (TSWV), which affects over 1,000 plant species including tomatoes, peppers, peanuts, and ornamentals
- impatiens necrotic spot virus (INSV), which affect ornamental plants like impatiens, chrysanthemums and various bedding plants.
Symptoms and transmission
Both TSWV and INSV are transmitted by small insects (thrips). The types of thrips that transmit these viruses include western flower thrips, tomato thrips, melon thrips and onion thrips.
The viruses are not spread by seed, equipment or manual handling, nor do they survive in soil or decaying crop residues.
They both produce similar symptoms which can vary widely and are often mistaken for other issues such as nutritional deficiencies or fungal infections.
Infected plants cannot be cured and should not be sold.
Status
- TSWV is widespread across Australia.
- INSV is newer and has been found in Victoria and New South Wales, with potential for wider spread.
Management
- Avoid selling plants suspected to have a viral infection.
- Manage weeds, as both viruses can infect weed species without showing symptoms.
For more information on the biology and management of viruses, including TSWV and INSV, see our recently updated factsheet or the webinar on viruses. If you think your plants may have a virus, send photos of symptoms to Grow Help or submit a sample for testing. Until the end of 2025, all production nurseries can submit six diagnostic samples to Grow Help each year for testing.