Barley Yellow Dwarf Virus
One of the many disadvantages associated with the early drilling of cereals is the problems associated with what is commonly classed as “Barley Yellow Dwarf Virus” (BYDV.)
Have no illusion, the virus is BAD and you do not want it in any of your crops, it depresses yield, quality along with heart and mind (you see it every time you walk in the field.)
Autumn 2020 has seen much “fear” heaped upon this virus. Let’s see if we can alleviate some of this.
Avoiding the virus.
Drill in October. If not, then as late as possible in September.
Minimising the damage.
Apply a pyrethroid insecticide.
Fear Factor Autumn 2020.
The one that is being played upon is the fact a significant percentage of the Grain Aphid population is “resistant” to pyrethroid insecticide which means if you spray your crop the chemical “won’t work” and you will still have BYDV in your crop in 2021.
Now the interesting bit.
AHDB published data for autumn 2020 shows that over a 10 year average the number of Grain aphids caught in the autumn throughout England is almost Zero.
AHDB published data for autumn 2020 shows that Grain aphids are not infected with the virus.
The Bird Cherry Aphid is the main vector (host) for BYDV.
It is present in significant numbers throughout England in autumn 2020.
Around 30% of the aphids caught and tested (in autumn 2020) are infected with BYDV.
Pyrethroid insecticides kill the Bird Cherry Aphid!
Where your crop has already emerged it is at risk of BYDV.
a) Apply the correct pyrethroid.
b) Application should be made at the appropriate crop growth stage.
c) Application technique should be optimised.
d) Environmental conditions will improve product performance.