Blue Sky Science: Do trees get viruses?

Molly Torinus

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Do trees get viruses?

Definitely trees get viruses. There are a wide range of different plant viruses that go not only to trees but to other types of plants as well.

Vegetables, fruits, herbaceous ornamentals– we see viruses on pretty much any type of plant. And that’s not actually the most important of types of organisms that cause disease. The most important group of organisms are the fungi.

There’s a disease called cedar apple rust. In mid-May to mid-June you start to see these huge really bright orange gelatinous masses that will start to form on junipers and particularly red cedar. That’s one of the fruiting structures of this fungus. It’s very visual and very pretty.

Fungi are much more complex. They form a variety of different structures oftentimes that are visible to the naked eye. They produce spores.

Viruses are quite simple. They’re basically just a piece of genetic material encapsulated in a protein coat. And if you put a virus out on an inert surface like a tabletop, it won’t do anything. It just sits there.

The only way it’s able to make more virus particles is if it infects its host, in our particular case, host plant.

Actually there are different ways that viruses can get into plants. Sometimes it’s just by touch, so you can have them on your fingers and handle plants and they will infect. Some are transmitted by insects. So aphids are a great group of insects that will move plant viruses around.

Plants tend to be smaller when they’re infected and then they get all kinds of funky growth distortions, they often have weird discolorations, ring spots; they get little yellow rings on the leaves.

Oftentimes they’re infected and they’re infected permanently, typically. The viruses just don’t go away.