Cucumber green mottle mosaic virus
Cucumber green mottle mosaic virus (CGMMV) is a virus which belongs to the genus Tobamovirus. It mainly infects plants within the Cucurbitaceae family, such as cucumber, watermelon, pumpkin and squash, but it can also infect non-cucurbit weeds such as blackberry nightshade, pigweed and amaranth.
CGMMV is known to be present in all Australian States and Territories except Victoria, Tasmania, and the ACT. It is also known to occur across Europe, Asia and North America.
Overall, CGMMV can cause major yield loss in cucurbits and reduce the marketability of fruits and vegetables. Symptoms of CGMMV vary from host type and can be temperature dependent. More severe symptoms are observed at higher temperatures whilst few or no symptoms may be observed at milder temperatures.
In general, infection symptoms include:
- mottling and mosaic patterns on leaves
- distorted and deformed leaves
- brown necrotic lesions on stems and peduncles
- stunted growth
- fruit drop
- sponge-like texture of the internal parts of fruit
- collapse of plants
For more information on the symptoms of CGMMV, please visit the Symptoms of CGMMV fact sheet on the Hort Innovation website.
Spread and management
CGMMV is highly virulent and easily transmissible. The most common means of spread is via contaminated seed and soil, as well as through touch transmission (either people or infected plant material).
CGMMV is also readily spread via contact with contaminated materials (e.g., tools and equipment) as it is extremely stable and can remain infectious on contaminated surfaces for a long time and in infested soil for at least 10-12 months.
To prevent the introduction or spread of CGMMV, the following measures can be put in place:
- stringent seed testing requirements for host plants
- routine testing of leaf material
- strict hygiene measures
- regularly monitor crops for symptoms
- report suspect symptoms
CGMMV is a declared exotic under the Plant Biosecurity Act 2010. Any suspect CGMMV should be reported online or by calling 136 186.
Market access conditions apply when importing CGMMV host material into Victoria.
For more information, please check Agriculture Victoria’s online Plant Quarantine Manual or email Market.Access@agriculture.vic.gov.au.