Wireworm In Potatoes

[eloog]

I've recently started leasing some land that was in continuous grass for years. I've noticed a good bit of wireworm damage on tubers. A neighbour recommended mustard as a biofumigant but advisor said I'd be wasting my time. Question is, what biocontrol are you guys using?

 

[Lincs Lass]

Pity Temic was withdrawn ,that nailed em

 

[ollie989898]

Don't grow spuds in that same land for s few years is all you can do. By not being in grass at all the wireworm will all become adults and not return.

 

[Sonoftheheir]

I've recently started leasing some land that was in continuous grass for years. I've noticed a good bit of wireworm damage on tubers. A neighbour recommended mustard as a biofumigant but advisor said I'd be wasting my time. Question is, what biocontrol are you guys using?

Looks like you’ve opened a can of (wire)worms!

Sorry!

Don’t think enough research has been done, I’ll pm you my agronomist’s no, he is a leading researcher on wireworm atm.

 

[Skater]

Pity Temic was withdrawn ,that nailed em

Actually it was quite poor on them.

 

[Skater]

I've recently started leasing some land that was in continuous grass for years. I've noticed a good bit of wireworm damage on tubers. A neighbour recommended mustard as a biofumigant but advisor said I'd be wasting my time. Question is, what biocontrol are you guys using?

You can have wireworms in land for many years after grass is pulled out. You can have a lot in land that has never been grass. We see a lot after 10 year stewardship, and 7 years later, still too bad to grow potatoes.
Seen onions taken out after 4 years of wheat recently. It is true that after 5 years or less they will become beetles, but they do not migrate, they may fly, but Agriotes (the main pest genus) is a weak flier and they do not move massive distances. If you have vegetation in land after grass, they will lay eggs there, and if the conditions are right, they will survive. All you need after cereals is a stubble left to regenerate naturally, its as good as a cover crop, most likely better if you include common buckwheat in a cover crop at more than 25% inclusion.

 

[Skater]

I've recently started leasing some land that was in continuous grass for years. I've noticed a good bit of wireworm damage on tubers. A neighbour recommended mustard as a biofumigant but advisor said I'd be wasting my time. Question is, what biocontrol are you guys using?

Its unlikely that a biofumigant, even if used well would result in a great reduction in damage the following year. Work was done as part of the Link project (Lole 2010) and the smart money would be on it reducing damage 2-3 years after the biofumigant.

 

[Northantsplants]

1. Radish can be used as a 'trap' crop, if that is feasible.
2. Some work has been done on pheromone traps.
3. What is your soil pH? If it is on the acidic side of the range that is optimum for potatoes, you could try raising it to the upper end that is optimal for potatoes as wireworms are thought to prefer acidic conditions.

No silver bullets there though...
Russ

 

[ganderman]

1. Radish can be used as a 'trap' crop, if that is feasible.
2. Some work has been done on pheromone traps.
3. What is your soil pH? If it is on the acidic side of the range that is optimum for potatoes, you could try raising it to the upper end that is optimal for potatoes as wireworms are thought to prefer acidic conditions.

No silver bullets there though...
Russ

We lost a 20 acre field to wireworm last year it hadn’t been grass in fifty years and the ph is at least 8 or above .

 

[ollie989898]

We lost a 20 acre field to wireworm last year it hadn’t been grass in fifty years and the ph is at least 8 or above .

What was the previous cropping? I've never seen wireworm attack a field like that completely out of the blue.

 

[Northantsplants]

We lost a 20 acre field to wireworm last year it hadn’t been grass in fifty years and the ph is at least 8 or above

 

[Northantsplants]

How is it looking this year?
Do you monitor with buried traps?

 

[ganderman]

What was the previous cropping? I've never seen wireworm attack a field like that completely out of the blue.

It very good Lincolnshire silt but poorly farmed with spring cereals and we rent it every five years for spuds.

 

[ganderman]

How is it looking this year?
Do you monitor with buried traps?

We have the next door field this year and they look good and have seen no sign yet. We did trap in the spring and it was ok that is this years field but didn’t trap last because never had an issue before .

 

[ollie989898]

It very good Lincolnshire silt but poorly farmed with spring cereals and we rent it every five years for spuds.

Ahh they must have moved in with the spring cereals, especially if it was left for long periods with a lot of volunteers etc.

 

[Fubar]

I think wireworm issues will only get worse going forward. Been living off all the good but now banned chemicals for the last few years. But lack of any effective treatments, grass margins, weedy stubbles and cover crops/ regenerative practices can only lead to a build up in numbers eventually. Seems to be a global problem so there must be a lot of research going into control. Although even if a chemical does come on to the market if will probably be banned over here.

 

[ollie989898]

Just need better stubble and field hygiene and to be more careful with what margins are put in, what species are in them and how they are managed.

No different to any other pest.

 

[Skater]

1. Radish can be used as a 'trap' crop, if that is feasible.
2. Some work has been done on pheromone traps.
3. What is your soil pH? If it is on the acidic side of the range that is optimum for potatoes, you could try raising it to the upper end that is optimal for potatoes as wireworms are thought to prefer acidic conditions.

No silver bullets there though...
Russ

I have been working with pheromone traps for 4 years now and we have about 30 sites round the UK where we are looking at adult activity. We in the Fera Enigma project are mainly looking at when they become active and the species present, from Aberdeen to Kent and so on. The species mix of Agriotes is expected to differ from North-South and East to West but I havent seen all the data yet. I know that historically sputator are not common in the North and from what we see in traps along the East over recent years they are dominant here.
You will have no success using pheromone traps to catch all the adults, and even if it did work, it would cost a fortune.
Re soil pH, yep we do see damage in high pH and cereals can be damaged more in chalky soils than clay but the soil texture is most likely a bigger factor.
The most critical factor in population survival is the need for the critical life stages to be supported. these are egg laying, hatch and juvenile survival.
My work has shown how we can predict adult activity pretty well now, certainly where I am and see what we can do to limit them.
Disruption of egg hatch is possible in certain crop situations
Juvenile survival, + disruption of any pupation or freshly pupated adults is best done with discs after a straw crop is harvested and straw cleared if no chopped.
Buckwheat in cover crops is supposed to reduce survival of the younger stages in particular, must be common buckwheat as far as we know.
If you leave cereal stubbles weedy every autumn, you may as well have grass in the field.

Would be interested to see work on radish as a trap crop, not quite sure what you mean by trapping them?
Biofumigation may kill juveniles.

There is an event on 26th September in Shropshire where this kind of work will be discussed.

Wireworm in potatoes field lab workshop and farm walk

Join us for a workshop and farm walk in Shropshire on wireworm in potatoes - management, identification and the latest field lab trials.

www.eventbrite.co.uk

The best way to reduce damage in potatoes is to have them all cleared by now, and processing tolerances are better.

As far as the story on glycoalkaloids and susceptibility?
My answer is that they seemed to like Innovator in a trial last year and Canadian work indicated that some time ago.

It is not just a UK problem
There will be 7 presentations at the EAPR conference in Arras in early Sept, there will be a presentation from the UK on recent development work, all of which is post AHDB potatoes and with minimal funding.
I self-fund all my own work but Enigma has industry funding and we also get support from Cupgra and Innovative Farmers.

 

[Skater]

Just need better stubble and field hygiene and to be more careful with what margins are put in, what species are in them and how they are managed.

No different to any other pest.

That is a massive part of it.
Spot on
Every situation, where I see problems in a non-grass situation, is either stewardship mixes for 2 years or longer, or weedy stubbles. Failing that, its successive cereals as that allows them to survive too.
I feel that with reduced cultivations and relatively benign seed treatments now, 2-3 cereals are nigh on as bad a s grass. And I have plenty of data to support this!
Cover crops are most likely going to be in there with weedy stubbles but it will depend on whats in your mix.
We have pretty much got rid of them on some farms, its hard work but when you are growing salad potatoes and have no chemical control, you have to get of your backside and work at it

 

[Skater]

I think wireworm issues will only get worse going forward. Been living off all the good but now banned chemicals for the last few years. But lack of any effective treatments, grass margins, weedy stubbles and cover crops/ regenerative practices can only lead to a build up in numbers eventually. Seems to be a global problem so there must be a lot of research going into control. Although even if a chemical does come on to the market if will probably be banned over here.

We could soon get a pyrethroid granule here, but its going to help, not cure it.
The product in Canada is very good, its called Cimegra.