How to tell TMV from CMV on tomatoes?

[Iva]

I apparently have a sort of a mosaic virus on some of my tomato plants. They were planted outside about three weeks ago and I culled all the affected plants by now.

I did take photos and will post them later but would like to know how you can tell apart these two viruses: CMV (Cucumber Mosaic Virus) and TMV(Tobacco Mosaic Virus)?

I'm really hoping it is the first one as that one does not stay in the ground. I only have a small garden and can not do crop rotation.

Please, I need help with this question!

[carolyn137]

Originally Posted by Iva

I apparently have a sort of a mosaic virus on some of my tomato plants. They were planted outside about three weeks ago and I culled all the affected plants by now.

I did take photos and will post them later but would like to know how you can tell apart these two viruses: CMV (Cucumber Mosaic Virus) and TMV(Tobacco Mosaic Virus)?

I'm really hoping it is the first one as that one does not stay in the ground. I only have a small garden and can not do crop rotation.

Please, I need help with this question!

Iva, I'll start by saying that TMV in an outside garden is very very rare these days. The last outbreak of TMV in an outside place in the US was perhaps 20 years ago, perhaps 1 or 2 other small outbreaks, I know one was in CA, and that's b'c all tobacco grown in the US, and I would like to assume elsewhere, has been TMV tolerant for many years. But that's not true of Turkish tobacco.

My Seminis tomato pathology monograph says that almost ALL cases of TMV are transmitted mechanically, not by insects, these days, and occur in large greenhouse operations at transplanting time.

However, to answer your question directly there's no good way to tell TMV from CMV b'c both have several strains so the appearance of both can vary as to stunted plants, chlorotic areas ( yellow) on the foliage, shoestring type foliage and much more.

So if you think you have the CMV virus, which is most probable, I'll wait to see your photos.

Viruses for both TMV and CMV do not stay in the soil b'c viruses need to replicate inside a living cell. But CMV has many many host plants such as 800 ones known to date that includes weeds and other crops. CMV is spread by aphids , actually many genera and species, so look to see if you have aphids on your plants first.

There are excellent photos for both infections at several of the Disease sites listed at the top of this Disease Forum, and I like TAMU b'c they use actual photos from the Seminis Lab which is THE best lab worldwide, and I also like the Cornell site, also listed here in this Forum.

Hope that helps.

[Iva]

Carolyn, thank you, you've calmed me down a bit. I've lost my plants but not my hope. I'm really hoping the darn thing won't spread. I've been researching the Internet (and all the sites you mentioned) for days trying to figure this out.

I did notice a few aphids today when I went to check out the plants again, will spray tomorrow. I have my eye on a few more plants showing symptoms. One of them is very different looking from all the others I've culled up to this point. Will take a picture of that one tomorrow.

But here are the pics of the plants that I've already pulled out of the garden.

Plant No.1:




Plant No.2:




Plant No.3:




Plant No.4:



Thanks for taking the time to help, I really appreciate it. Hope you are doing better health vise

[carolyn137]

Iva, I just took a quick look at your pictures and a quick one b'c we have a severe weather warning here and I'm shutting down my computer ASAP. I did notice that Lee had a thread about CMV in this Forum.

Will be back when it's safe to and this warning goes through tonight, so if I can peek in OK, and maybe even some others will contribute to your dilemma and comment on your pictures.

Having my home hit by lighting a few years ago and with this walker unable to go anywhere quickly and if the phone is out, well, I don't want to go there.

[Iva]

Carolyn, thanks for the quick reply.
I did read all the threads I could find here but still can't figure out what's wrong with the plants. Maybe it's because I've pulled all of them out in a very early stage of the disease when the leaves were only mottled with green and yellow and not showing any other typical deformations...

I'm still worried about a couple more plants showing symptoms and am taking pictures (which I will post later again) so I can figure out what it is.

I hope you (and your computer) got through the storm unharmed