Information and discussion regarding garden diseases, insects and other unwelcome critters.
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June 1, 2016 | #1 |
Tomatovillian™
Join Date: Jan 2016
Location: MS
Posts: 211
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Dark gray spots
I've never seen dark spots shaped like this on tomato plants before. It is only on my potato leaf variety, Big Cheef. We have not had any rain here for a month, so the foliage has been dry. It's only on a few of the leaves which are located high on the plant, not lower leaves. No sign of damage in the underside, only discolored on the top. I only see it on 4 leaves on a 3 ft tall plant. I'm not sure what it is. Hoping someone here can help me figure this out.
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June 1, 2016 | #2 |
Tomatovillian™
Join Date: Jan 2016
Location: MS
Posts: 211
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Well, I just found a leaf where it is visible underneath.
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June 1, 2016 | #3 |
Tomatovillian™
Join Date: Jun 2012
Location: Illinois, zone 6
Posts: 8,407
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It doesn't look good, whatever it is.
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June 1, 2016 | #4 |
Tomatovillian™
Join Date: Jan 2016
Location: MS
Posts: 211
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June 1, 2016 | #5 |
Tomatovillian™
Join Date: Jan 2014
Location: Southern WI
Posts: 2,742
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I feel your pain. I do the same and it always happens. Comes in on the raindrops unfortunately.
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June 1, 2016 | #6 |
Tomatovillian™
Join Date: Sep 2009
Location: Alabama
Posts: 7,068
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Keep a close eye out for this spreading and watch the plant to make sure it is still growing. In a few days or a week if the new growth looks healthy then at least it isn't Tomato Spotted Wilt Virus which can start as just a rust like appearance on a few leaves in colors from dark yellow to black. If it is TSWV the plant growth will slow to a standstill and the new growth will take on an almost scorched appearance with some shriveling. Eventually the whole plant will take on an unhealthy appearance and eventually die.
Hopefully this is not what you are dealing with but I have last a few tomatoes and even more bell peppers to it this year so it is something to be aware of. Bill |
June 1, 2016 | #7 |
Tomatovillian™
Join Date: Mar 2014
Location: Greenville, South Carolina
Posts: 3,099
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Hate to say it but looks like TSWV to me. Hoping it isn't but I'd probably pull that plant and take it to your extension office if possible.
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June 1, 2016 | #8 |
Tomatovillian™
Join Date: Aug 2011
Location: Plantation, Florida zone 10
Posts: 9,283
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I'm thinking it's Bacterial Speck.
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June 1, 2016 | #9 |
BANNED FOR LIFE
Join Date: May 2014
Posts: 13,333
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I was thinking it looks like Bacterial Speck too.
I don't know anything about TSWV other than reading some hybrids have resistance to it. |
June 1, 2016 | #10 |
Tomatovillian™
Join Date: Jan 2016
Location: MS
Posts: 211
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I'm not sure if this helps diagnose, but it seems that the spots first appear at the stem end of the leaf and progress towards the tip.
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June 1, 2016 | #11 |
Tomatovillian™
Join Date: Jan 2016
Location: MS
Posts: 211
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June 2, 2016 | #12 | |
Tomatovillian™
Join Date: Jan 2016
Location: MS
Posts: 211
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The more I read about the differences between Bacterial Speck (and B. Spot) and Tomato Spotted Wilt Virus, the more I think that this is TSWV. I removed the 4 leaves showing signs and threw them in the trash.
Quote:
I'm considering pulling the whole plant and disposing of it to reduce any chances of it spreading to other plants. Bill, can you tell me your experience with it spreading to other plants? Is it rapid, random, infrequent, etc? And if I do find it on other plants, how long can I expect it to take for the entire plant to succumb? I'm just thinking out loud and weighing options, with consideration given to protecting the rest of the garden. |
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June 2, 2016 | #13 |
Tomatovillian™
Join Date: May 2008
Location: DFW, Texas
Posts: 1,212
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TSWV is vectored by thrips (western flower thrips). They are a major problem every year for me, though it took me years to realize it because they are so dang tiny. Primarily, they destroy tomato blossoms so you end up with much less fruit set, but, they can bring TSWV and mess up the whole operation. I don't know about air borne transmission, but, if you have thrips and TSWV, it is extremely easy for them to spread it to multiple plants. I would inspect for them and if you have them, start treating for them ASAP.
I'm not sure what really works on them. Some things that claim to treat them are Spinosad, neem oil, and pythrethrum. There are natural enemies available. Personally, I've not found anything that eliminates them, though perhaps I should try spraying more frequently to do a better job interrupting their life cycle. Hopefully, it is bacterial speck, which will be much easier to treat. Good luck. Dewayne mater |
June 2, 2016 | #14 |
Tomatovillian™
Join Date: Jan 2016
Location: MS
Posts: 211
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New photos from today. This does not look good. Black streaks on the stems may be the definitive sign of TSWV. I can't find any thrips on the plant, but maybe that's a good thing because then they aren't around to spread it.
I guess I better yank this plant today. Ugh!! |
June 2, 2016 | #15 |
Tomatovillian™
Join Date: Mar 2014
Location: Greenville, South Carolina
Posts: 3,099
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Yep unfortunately you have TSWV. You most likely have thrips but don't know it.
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