[tode]

My neighbour (on the other side of the road) came to tell me that his tomatoes had keeled over. Went to see, and sure enough, the top foot or so of his 3 -4 ft high plants had completely wilted. He's been watering, and we had some rain the night before.
The first 2 - 3 inches of the stems (at ground level ) are black, but no other discoloration on the plants.
Is this blight? I thought that blight spread slowly over the whole plant?
If not, what is it.
It was only 3 or 4 days ago that I complimented him on the health & strength oh his plants
Any ideas?

[Paul Plots]

If it were blight there would be discoloured patches (dark brown/ black and grey-white underneath) all over the leaves and, eventually black, in several places on the stems and thinner 'branches'.

I've heard of something called "black leg" but not sure it is related to tomatoes.. 

Sounds as if the plants have some type of virus - maybe due to the sol being too wet?
If the capillary cells were damaged this would cause the top to wilt as it is the last to receive water...

I'll look it up later when I come back from the plot.

[down the lane]

I have just dicovered a similar problem with my potatoes. I've narrowed it down to a bacterial infection called "blackleg" which seems to have come from infected seed potatoes. I don't know if tomatoe plants can get blackleg but it may be worth researching.

[Yorkie]

The RHS page on black leg suggests that it doesn't affect tomatoes, but it does sound a little like it, they are the same family, and there's nothing on the tomato page which looks similar

http://www.rhs.org.uk/Advice/profiles0902/potato_rot.asp

[tode]

What seems strange is that the (unwilted) leaves and the green tomatoes look absolutely fine (look healtier than mine !).

[tode]

Heres a pic of one of his plants. The blackened part is dry and shrunken.
Anyone any ideas?

[scabs]

Just had a mooch on the RHS site and the closest thing appears to be blight... though you say the leaves look healthy?

Have you put down any manure? Perhaps herbicides?

[tode]

He's only watered from time to time. No sprays or mulch.
He gave them a spry with Bordeaux mixture after the attack (out of desperation), but I dont think that will help, since there are no traces on the leaves.
The top third of the plants have wilted.
I suppose it must be blight, but it seems strange.
I just wish he hadn't come to tell me the bad news in my greenhouse!

[Paul Plots]

Just had a mooch on the RHS site and the closest thing appears to be blight... though you say the leaves look healthy?

Have you put down any manure? Perhaps herbicides?

That's hit it on the head!! 

I bet manure has been added to the ground and the manure contains some of that recently-discussed-a-lot chemical weed killer.

I say this as my plot neighbour had similar problems with his greenhouse tomato crop... All looked fine then suddenly the top growth flopped, lower leaves curled and the whole lot came to a stand still. I'd forgotten that this might be a astrong possibility as I was concentrating on it being to do with blight or some other fungal infection.

News sounds bad to me - If the plot has had recently added farmyard manure I bet that's the main problem...... damage due to residual chemicals.

[Ice]

Could be stem rot, Didymella.  Have a google for it.

[tode]

Thanks Ice, it sounds very much like his problem. He's grown toms in the same place for a few years, and had recently hoed around the plants, so maybe he bruised the stems.
He hasn't used manure (in fact, he doesn't really use anything), so it cant be weedkiller.
The rest of his garden looks fine.

Maybe its not such a good idea stripping off the lower leaves, either, since apparently Didymella can be transmitted by slashes from ground onto wounds.
Makes you think,
Thanks.

[Yorkie]

I'd be very surprised if it could be the manure in any event at this stage of the season, the aminopyralid problem shows itself much earlier in the growth cycle of the plant.

Not sure about the piccie of the stem, but the leaves are showing a clear nutrient deficiency - the yellowing.  Suggest epsom salts or a balanced nutrient feed.  Has he been overfeeding with tomato feed?

[tode]

Yorkie: he doesnt feed at all, but weve had a month of very hot dry weather, and its just the lower leaves like that. The major part of the plants have/had rich green leaves, not even curled-up like mine.

[Paul Plots]

I've just searched the net for "Didymella" having never heard of it.

One site says: "Gummy stem blight shows a variety of symptoms which are referred to as leafspot, stem canker, vine wilt, and black rot"

Not quite the "black leg" I was thinking of in an earlier post but similar!! 

So manure / weed killer residual out... I think Ice may well be right.... Clever thing!!