Potato plant wilting

[muckdiva]

Something similar happened to two of my crimson flowered broad beans, all other plants ok. Assume it must have been slugs attacking the stems but weird that the leaves seemed normal.

[ameno]

That is a moth, but it's completely unrelated. This was taken on my bedroom windowsill, and that's a dead clothes moth. We have a minor infestation right now.

I did consider insect damage, but I wonder what could have caused it if it is. Wireworms aren't big enough to cause such damage, nor are leatherjackets, really, and either way I'd have thought I would have seen at least one or two if they were the cause. Cockchafer larvae is a possibility, but they'd have to be in the soil in some numbers, and I'd have thought I would have noticed when I dug it over if that were the case.
Personally, I think it's probably either underground slugs eating the stems (perhaps the dry weather has driven them underground to more unorthodoxfood sources?), or some sort of physiological condition, perhaps splitting caused by drought or water following drought, and then the damaged stem snaps off completely in the wind or something.

[Jungle Jane]

I wonder if it’s an insect,are any plants next to that one affected? Is that a moth in the photo -

[Penellype]

Well, like I said above, it doesn't seem to be blackleg. There's not blackening at all, and no rotting, either.

Sorry, I didn't see your earlier post as it was posted while I was writing mine. I agree it doesn't look like blackleg, no idea what it is, sorry.

[ameno]

Well, like I said above, it doesn't seem to be blackleg. There's not blackening at all, and no rotting, either.

[Penellype]

I will check for blackleg, but I rather doubt it's that. I mean, doesn't that take time to develop? These are maincrop; they've only been in 6 weeks. The leaves aren't even fully grown yet.

I'm not sure how long it takes to develop - the earliest I have had it has been 15th May on Lady C planted in March. I find Lady C is quite susceptible, but I have also had it once on Sarpo Mira and once on Charlotte - I haven't grown Rooster. I find it tends to be worse in dry years when I'm watering every day with a watering can, presumably wetting the stems rather more than would happen from rain. This is backed up somewhat by a lower (but not zero) occurrence in self watering planters compared with buckets.

[ameno]

Well, I pulled up the wilting plant, and the stems were indeed severed about 3 inches below the soil surface.
What by, though, I don't know. It's not black at all, or otherwise discoloured, or soft and pappy, so I'm fairly sure it's not blackleg or any other kind of rot.

The stems seem to have a hollow groove carved into them, and at one point that goes all the way through and severs the stem.
The worrying part is that I carefully brushed the soil away to check on other potatoes, and several of them have the same damage (a deep hollow groove running up the stem for a couple inches), although as yet it hasn't severed the stems of any of the others.

Here are some photos of the damage bits:
https://i.imgur.com/wkk8G65.jpg
https://i.imgur.com/Ps5Tlpf.jpg
https://i.imgur.com/iMGrryN.jpg

[ameno]

I will check for blackleg, but I rather doubt it's that. I mean, doesn't that take time to develop? These are maincrop; they've only been in 6 weeks. The leaves aren't even fully grown yet.

[Penellype]

Check the bottoms of the stems for blackleg - the stems go black and rot at ground level and the first sign of this is often that the plant wilts. The rot spreads down to the potatoes which then go black and rotten. Potatoes that are harvested when the disease shows are ok to eat, although you often find a small black area where the potato joins the plant.

I have found that if you remove affected plants the disease doesn't spread to the others, but I wouldn't risk leaving a plant with blackleg in the soil.

[rary]

I would definitely check for breakage or slug damage, failing that carefully remove the soil to check the tubers of the wilting plant to see if there is anything wrong with them

[Stan79]

I’m watering daily! In the heat and the wind they’ve been taking a bit of a battering!

[ameno]

It was windy,did you have a close inspection to see if there were any breaks in the stems? Where did the seed potatoes come from,were they proper or from the supermarket?

Seed potatoes from Wilko. Rooster. I planted 15 of them, and the other 14 all seem fine, and even this one isn't showing any signs of disease (yellowing leaves, spots, that sort of thing). It just suddenly started wilting.
I haven't checked the stems properly yet; it's possible something severed them. I shall give them a gentle tug tomorrow, and see if they are still well anchored.

[burnie]

Me and the local farmers are watering just now, every couple of days for mine with a hose for 5 minutes.

[Jungle Jane]

It was windy,did you have a close inspection to see if there were any breaks in the stems? Where did the seed potatoes come from,were they proper or from the supermarket?

[ameno]

I noticed this evening that just one of my potato plants was badly wilting. It was absolutely fine yesterday, and the whole thing is still green and healthy (apart from the wilting), so I don't think it's a disease of any sort. It seemed like normal dehydration, but the soil wasn't parched (it was a bit on the dry side, though), and the others were all fine.
For now, I've given it a good soaking, but any ideas what might be causing it?