BYDV, the green bridge, cover cropping and no till?

[Michael S]

Given the absence of Deter and that most of us are looking to minimise the use of foliar insecticides and the general acceptance that no till establishment of crops is best done sooner rather than later what is the best way to square the circle where the CA principle is always having a growing crop in the ground? Is it best to minimise green cover by terminating early or drill later or both?

 

[SilliamWhale]

I don't know. I've done it all ways and to be honest I'm not sure I'm totally into the green bridge theory totally. I think its more complex. I think we've been encouraged to think that "crop hygiene = brown soil and therefore no habitat for bugs but I don't think its any more reliable a theory than having lots of green surface trash dying off and the new crop coming through - after all mother nature doesn't mind too much green around her does she? THe BYDV aphid isn't the only aphid on the scene

At the moment my strategy is generally been to drill a bit later - ie from now to October and spray off after drilling. I had no bydv disasters I can recall and gave up deter 2 years ago.

 

[rob1]

didnt use deter last year and didnt see any bydv, was it because we dd and so the beneficials keep the bad guys under control or were we just lucky, guess we will know more this year

 

[Michael S]

Thank you, sounds encouraging.

 

[cows r us]

The only bit of bydv that we saw last year was in the last field we drilled at the end of November. We don't use insecticides and often have a green bridge.

 

[yellow belly]

The green bridge depends on what is green and what is planted

Osr volunteers planted with wheat on the green do not harbour bydv carrying aphid

Oat volunteers drilled with wheat are a different matter
Oats need killing early and green bridge prevented for bydv but also fruit fly risk

Oilseed rape grow a variety resistant to turnip mosaic virus if you can get rape past the flea beetle

 

[Clive]

I’ve never used deter

I’m not convinced you need it as much as you have all been convinced you do

if it’s just luck using not insecticides I must be the luckiest guy alive

@yellow belly post above is sound advice