Aphids in non deter cereals

[T Hectares]

My Wheat is mostly mid to late October sown non deter treated, I followed the ahdb prediction tool and sprayed one hallmark at the timing the tool indicated.
I'll hang on now for the frosts now, we've had quite a few -3 temps since the new year and with more predicted I'll sit tight and see, if weather stays mild I'll follow up in the early spring, if we get the frosts I'll be OK I think.
I've one Deter dressed field for comparison which should have run out around Dec 15th.

 

[fudge]

As my friend Mr Gove looks likely to encourage me to move to zero till I have been wondering if anybody has noticed an increase in bydv risk with the use of cover crops? Generally I drill mid October onwards and I am quite fastidious about not allowing a “green bridge” between crops. Under zero till, at least in the first instance, I would not continue with second wheat, if that makes any difference. Sorry this is a bit off topic.

 

[jonnyjon]

As my friend Mr Gove looks likely to encourage me to move to zero till I have been wondering if anybody has noticed an increase in bydv risk with the use of cover crops? Generally I drill mid October onwards and I am quite fastidious about not allowing a “green bridge” between crops. Under zero till, at least in the first instance, I would not continue with second wheat, if that makes any difference. Sorry this is a bit off topic.

I have not

 

[Hindsight]

My Wheat is mostly mid to late October sown non deter treated, I followed the ahdb prediction tool and sprayed one hallmark at the timing the tool indicated.
I'll hang on now for the frosts now, we've had quite a few -3 temps since the new year and with more predicted I'll sit tight and see, if weather stays mild I'll follow up in the early spring, if we get the frosts I'll be OK I think.
I've one Deter dressed field for comparison which should have run out around Dec 15th.

With a 15 to 28 October sowing date I presume your wheat emerged roughly in period 2 November to 28 November.

You are in a completely different part of world to me so will know your local circumstances but my question for you is did you find or do you think (or mixture of both) that aphids migrated into your crops given, if my assumptions are correct, the relatively late emergence date of crops in relation to end of aphid migration (or maybe you consider migration has not ceased?)

Several presumptions and questions in there.

Am interested in how others decided on treating for aphids. In my part of the world I have not treated anything sown after about October 10.

Regards

 

[T Hectares]

With a 15 to 28 October sowing date I presume your wheat emerged roughly in period 2 November to 28 November.

You are in a completely different part of world to me so will know your local circumstances but my question for you is did you find or do you think (or mixture of both) that aphids migrated into your crops given, if my assumptions are correct, the relatively late emergence date of crops in relation to end of aphid migration (or maybe you consider migration has not ceased?)

Several presumptions and questions in there.

Am interested in how others decided on treating for aphids. In my part of the world I have not treated anything sown after about October 10.

Regards

I used this tool...
https://cereals.ahdb.org.uk/bydv
To help time the insecticide, the first drilled on Oct 8th was through by the 13th and was at threshold by the 25th and it was still very mild, the last drilled on Oct 20 -25th and emerged by Nov 1st hasn't been treated.

First year without Deter and I've cautiously treated the earlier sowing, next year I will spend more time trapping aphids and going more by the results of that.

 

[Hindsight]

I used this tool...
https://cereals.ahdb.org.uk/bydv
To help time the insecticide, the first drilled on Oct 8th was through by the 13th and was at threshold by the 25th and it was still very mild, the last drilled on Oct 20 -25th and emerged by Nov 1st hasn't been treated.

First year without Deter and I've cautiously treated the earlier sowing, next year I will spend more time trapping aphids and going more by the results of that.

Ah, so the crops had emerged earlier than my presumption. I assumed you had nothing emerged until into November. I used the AHDB tool too although I was aware of the Tsum calculation above 3C. I am awaiting a period of frosty weather! Hopefully in next few days. Hey ho.

 

[yellow belly]

the biggest issue with those who spray is that some aphids will not be controlled either resistance or just poor efficacy

if you spray twice then the preditor inscect will be anialated leaving the surviving aphids to be unchecked and have a free reign

it take 4 years for beneficials to recover

on notill the beneficials are in greater nos as they are not controlled by cultivations which destroy their habitat by destroying there homes

 

[shakerator]

the biggest issue with those who spray is that some aphids will not be controlled either resistance or just poor efficacy

if you spray twice then the preditor inscect will be anialated leaving the surviving aphids to be unchecked and have a free reign

it take 4 years for beneficials to recover

on notill the beneficials are in greater nos as they are not controlled by cultivations which destroy their habitat by destroying there homes

It sounds good and logical but I don’t actually think it’s true.

BYDV strikes wild grasses in totally undisturbed habitats where one would imagine ecosystem balance would be at its best.

I agree no till with residue provides an armour of protection for spiders beetles etc- I don’t think pyrethroids have a deleterious impact at all in this scenario. Hardly deleterious on a certain beetle in OSR

 

[fudge]

Realistically we will soon be managing the bydv risk without any insecticide. Good understanding of cultural controls will be needed. Personally I feel a bit lacking in knowledge. What rotation? What drilling date? Cover crop or not?
Certainly interesting to hear people’s views.

 

[jonnyjon]

Realistically we will soon be managing the bydv risk without any insecticide. Good understanding of cultural controls will be needed. Personally I feel a bit lacking in knowledge. What rotation? What drilling date? Cover crop or not?
Certainly interesting to hear people’s views.

Grow healthy, high nutritionally dense plants and aphids can't/ won't feed on them

 

[Right-arm fast]

Well I sprayed the fields in question so with this bit of cold weather hopefully that will be all we need to do now. Not too worried about the deter dressed wheat at the moment.

 

[Hindsight]

Well I sprayed the fields in question so with this bit of cold weather hopefully that will be all we need to do now. Not too worried about the deter dressed wheat at the moment.

Just wondered if you left a tramline or two untreated for comparison? Interesting education.

 

[yellow belly]

It sounds good and logical but I don’t actually think it’s true.

BYDV strikes wild grasses in totally undisturbed habitats where one would imagine ecosystem balance would be at its best.

I agree no till with residue provides an armour of protection for spiders beetles etc- I don’t think pyrethroids have a deleterious impact at all in this scenario. Hardly deleterious on a certain beetle in OSR

Not had bydv over the years what ever cultivation in late September or October planted crops October emerged crops
Imho where I am they do not thrive and multiply to a damaging level
Before winter or benificials do them in

The percentage of aphid infected by bydv has been shown to be very low

I have seen badly affected crops back when crops had emerged by mid September in Lincolnshire
and ploughed grass which carried the aphids over october planted in Dorset
In the 70s direct drilled crops the use of gramoxone killed the aphids reducing carry over
Now with kinder glyphosate carry over is a potential infection especially on cover crops although early planted cereals do not usually follow a grass based covercrop brassica cover or osr volunteers do not have bydv carrying aphids

 

[Andrew K]

Not had bydv over the years what ever cultivation in late September or October planted crops October emerged crops
Imho where I am they do not thrive and multiply to a damaging level
Before winter or benificials do them in

The percentage of aphid infected by bydv has been shown to be very low

I have seen badly affected crops back when crops had emerged by mid September in Lincolnshire
and ploughed grass which carried the aphids over october planted in Dorset
In the 70s direct drilled crops the use of gramoxone killed the aphids reducing carry over
Now with kinder glyphosate carry over is a potential infection especially on cover crops although early planted cereals do not usually follow a grass based covercrop brassica cover or osr volunteers do not have bydv carrying aphids

How high are you above sea level YB?

 

[yellow belly]

With this weeks frosts aphids if they carried bydv or not will be much reduced
Spraying was a waste of time and most likely will make potential future pest epidemics worse