Topic: Potato Black Leg

[lisaparkin]

Our 'Allotment neighbour' has potatoes with Potato Black Leg.  I have 'googled' it to find out more, just wondering if anyone else has ever had this problem?  :'(

http://apps.rhs.org.uk/advicesearch/profile.aspx?pid=223

[Kea]

Must be warm and moist where you are. Some potato varieties are more did susceptible than others. The bacteria that causes the disease also causes soft rot in the tuber during storage. If the affected plants have tubers then they should be used not stored. Affected plants should be removed as the disease will spread.

[cornykev]

As Kea said it has to be in wet and heavy soils and considering it's been nearly rain free here since Feb I'm scratching my head, did your neighbour cut the spuds in half before planting, this increases the risk of disease.     :-\

[powerspade]

Tell your neighbour to dig them up and burn them straight away

[smudger28]

3 of our new potato plants "Lady Christl" have been infected.  They turned yellow and rotted at the stems.  We have had no rain for months down here in Cornwall.  I destroyed the plants.  I thought it was blight at first..

[Allotment-junkie]

I believe one of the main causes of Blackleg is the Tuber getting bruised in storage

[chriscross1966]

Wow.... that's one of the old ones  :o... you really don't see Blackleg much any more.... I'm in agreement with whoever pointed it out it might be bad handling of the seed tubers before they got to you, certainly in the south we've not had enough rain for it to be somethign you'd expect...

[Kea]

I spent 3 years working on a project to find a biological control for this disease and we did but it can't be used. It was a well funded project because this disease is a problem and still a problem...not one of the old one's I'm afraid.

You don't need rain just high humidity. The infected potatoes can look perfect I assure you if they're bruised they don't last long enough in storage to be planted. I use my nose when buying potatoes for eating as my familiarity with the disease means I can smell it long before it can be seen. I do get strange looks in the supermarket.

Some varieties are more susceptible than others, for our experimental work we used Maris Bard. Close planting increases the spread as does walking through the crop.

[green lily]

I thought blackleg came [or was made more likely] frpm using muck in the trenches. Having has it when I did used muck some years ago I now use compost and newspaper to hold the water and have had no further problems. Don't know if this applies in any of your cases

[queenbee]

My Lady Christl have also suffered from black leg. This is the first time I have ever had it. I just hope it doesn't spread to my other varieties which are looking very healthy. I must be a fault in the seed rather that any other factor. It is the first time I have grown Lady Christl.

[lisaparkin]

Thank you for all the replies.  My 'allotment neighbour' has dug out all 'infected' potato plants.  He is retired so is there every day and is keeping an eye on them all.

[Allotment-junkie]

The infected potatoes can look perfect I assure you if they're bruised they don't last long enough in storage to be planted. I use my nose when buying potatoes for eating as my familiarity with the disease means I can smell it long before it can be seen. I do get strange looks in the supermarket.
.

would you be assuming the Tubers had been roughly handled Months before they were put on the shelves ?, for them to rot it would take many weeks for any smell to be there the point is that the Tubers may have been mishandled or stored incorrectly in transit from the suppliers to the outlet only Days/weeks before you may have purchased them and therefore after a short time in the ground this disease would rear its ugly head. Sorry but that is my theory on Blackleg

[manicscousers]

We've had some kestrel and smile like this, must have a word with our supplier, he gets them from Scotland, puts them into smaller bags and delivers them, I'll also have a word with the other people who bought them from him, does it stay in the soil?

[Kepouros]

It will remain in certain soils (the heavier wetter ones) but in medium and light soils does not generally do so for very long, and will disappear with normal crop rotation.

I was plagued with blackleg for 3 years some time ago.  I`d been growing potatoes for almost 60 years and had never seen it before, but suddenly it appeared, and I lost 20% of my crop.  I wrote to my seed suppliers and was told that it was nothing to do with the seed and it must be in my soil.  To establish the truth I deliberately planted more potatoes (from a different source) on the ground the following year and they were all clean.  After that I changed my supplier and have not seen any blackleg since

[gwynleg]

I think I might have this as one potato plant only has black stem, and yellow leaves but the tubers have grown and seem ok (at the moment!). Have carefully disposed of the plant.

Does it seem likely that this is black leg?

[Allotment-junkie]

It sounds like it to me the Tuber only needs to get bruised in storage, it is  not a disease that affects your whole crop(unless you are one of the unlucky ones and the whole bag of seeds potatoes have been bruised) but like yourself you can get the odd one here and there , there may be lots of very tiny marble size tubers in the ground under the plant make sure you get them all out of the ground otherwise you will be plagued with Volunteers Next year. 

[Kea]

There is no 'if' tubers are roughly handled they are always roughly handled...always by commercial growers.