Mosaic Viruses
Cucumber mosaic virus, Zucchini yellow mosaic virus
A family of viruses causing mottled, distorted leaves and deformed fruit across tomatoes, cucurbits, beans and peppers.
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Identify from a photoBackground
Mosaic viruses are a diverse group. Cucumber mosaic virus (CMV) has one of the widest host ranges of any plant virus, infecting tomatoes, capsicums, cucurbits, ornamentals and weeds. Tomato mosaic virus (ToMV) is mechanically transmitted and can persist in seed and debris. Zucchini yellow mosaic virus (ZYMV) severely distorts cucurbits and is aphid-transmitted.
How to identify
- Light and dark green mottling (mosaic pattern) on leaves
- Leaf distortion. Narrowed or strap-like leaves, puckered surfaces
- Stunted plants, poor yield
- Fruit with mottled skin, bumps or distortion (ZYMV on zucchini is striking)
Life cycle
CMV and ZYMV transmitted by aphids in a non-persistent manner (seconds of probing can transmit). ToMV is mechanically transmitted: hands, tools, contaminated seed. Many alternate weed hosts.
Weather triggers
- Temperature: 15-32°C
- Follows aphid activity for CMV/ZYMV. ToMV is weather-independent.
Peak season (southern hemisphere)
Red = active season · Dark red outlined = this month
Affected vegetables & crops
Click any crop to see current prices and growing info.
Climate zones at risk
Organic & low-impact control
- Remove infected plants promptly
- Control aphids to slow spread
- Wash hands and tools between plants when handling tomatoes (for ToMV)
Chemical control
- No chemical cure
Always read product labels. Registrations change.
Prevention
- Choose resistant cultivars (especially zucchini and cucumber cultivars with ZYMV resistance)
- Control aphids and their weed reservoirs
- Use clean seed
- Avoid tobacco handling near plants (TMV)
Companion planting
Flowering insectary plants reduce aphid numbers and thus spread of CMV and ZYMV.
Biosecurity
Some virus strains are reportable.
Know when Mosaic Viruses is actually about
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Live pest pressure, for your postcode
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- Queensland fruit fly tracking
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