Published on 03/10/2024
These were two common questions the Bayer team encountered during the run up to spring.
There is no doubt that input costs and cashflow are a key concern for everyone this spring.
As part of the discussion about options to reduce input costs, fungicides use is being questioned: Can we reduce the number of fungicide applications, or the fungicide dose used?
Without effective disease control, yields can be devastated and, with it, profit.
A comparison of CPT trials1 compared the yield of a range of wheat varieties over four years with and without fungicide applied.
The average yield decline from not applying fungicides was 4.1 tonnes, worth $1730 per ha (wheat at $420/tonne). Even the lowest yield decline was worth$1050 per ha.
There is no doubt that applying a comprehensive fungicide programme delivers a great return on input cost and farmers should look elsewhere to save costs.
Fungicides are essential for growing profitable cereals, but fungicide resistance is a constant threat. With several important DMI fungicides (Prosaro and Proline) and SDHI fungicides (VIMOY iblon, CALEY iblon) for use on wheat and barley, this is a very important subject for Bayer.
There are some important factors that help maintain fungicide effectiveness which all fungicide programmes should embrace:
1) Applying the full label dose rate for DMI fungicides such as Prosaro is very important. Applying reduced doses of DMI fungicides can accelerate the shift towards reduced sensitivity by fungi.
2) The benefit of mixing different fungicide types to protect against fungicide resistance is well recognized. But to be effective, all fungicides in the mix must control all diseases and for a similar length of time. Applying a mixture of Prosaro and VIMOY iblon will do this but it isn’t the case with all fungicide mixtures so check the ones you plan to apply this spring.
3) Modern cereal fungicides tend to control disease for around four weeks so ensure the time interval between successive fungicide applications is between25-28 days.
Prosaro contains two DMI fungicides -prothioconazole and tebuconazole. Applying two different, but complimentary, DMI fungicides is known as DMI stacking. This is a very effective way of boosting disease control, and it enables Prosaro to very effectively control the key arable diseases.
Prosaro is very effective when applied at all crop growth stages, but it tends to be applied early in the season, at GS30-32 for wheat and barley. It is also commonly used at ear emergence in wheat, at GS60-65.
VIMOY iblon is a very effective SDHI fungicide for use on wheat, barley and ryegrass seed crops. It controls most of the key arable diseases, being particularly effective against speckled leaf blotch and leaf rust in wheat, and scald, net blotch and leaf rust in barley.
Bayer NZ trials have demonstrated that the exceptional disease control provided by VIMOY iblon can lead to the retention of healthy leaves and high yields.
The key application timing for VIMOY iblon is at flag leaf for both wheat and barley.
For further detail contact your local Bayer field team.
Words: Neil Waddingham, Bayer
1.FAR Autumn Round Ups booklet, 2023.