The time for critical fungicide application is approaching fast

Whether you are growing wheat or barley, the time to apply flag leaf (GS39) fungicide is approaching fast. For both crops, but for different reasons, this is a very important fungicide application.

For wheat the top two leaves deliver around 65 percent of the crop’s yield so it is critical to protect them from disease attack by applying a robust fungicide. The key diseases attacking wheat at this time of year are speckled leaf blotch and leaf rust. Both of these diseases are capable of devasting yields if not controlled. Stripe rust will also be lurking, another aggressive disease but one which tends to strike earlier in spring. However, it can attack until ear emergence if there are cool, moist weather conditions. For barley it is a different story. Barley tends to develop most of its yield from the lower leaves and stem but it remains extremely important to protect the flag leaf. Applying a SDHI fungicide mixture to the flag leaf is the best tool we have to manage ramularia leaf spot (RLS) and to delay the onset of symptoms. This is despite testing showing that most RLS isolates are resistant to SDHI fungicides. While the exact reason SDHI fungicides continue to show a positive effect against RLS isn’t clear, it is likely that by keeping the plant healthier these fungicides are helping to delay the onset of RLS symptoms.

| Applying CALEY iblon at flag leaf emergence will help ensure a successful harvest.

With CALEY ® iblon ® , a powerful new fungicide option is now available, one ideally suited for application at GS39. Iblon is a brand new SDHI fungicide (active ingredient — isoflucypram) and this spring New Zealand farmers will be the first in the world to benefit from this highly effective fungicide. CALEY ® iblon ® is a ready formulated mixture of iblon and prothioconazole registered for use in wheat, triticale, barley and ryegrass seed crops. Trialled extensively in NZ, it delivers outstanding, long-lasting control of all major diseases in a convenient, easy to use formulation. Roy Stieller, Senior Product Development Specialist for Bayer in Canterbury, was responsible for the development of iblon ® fungicide technology in New Zealand. “Iblon is such an impressive fungicide, it is fair to say the best I’ve seen,” Stieller explains. “Under intense disease pressure CALEY ® iblon ® provides excellent disease control which in turn delays crop senescence, boosts yield and gives higher profits. Farmers want to maximise profits and here CALEY ® iblon ® excels.” David Parker, Bayer regional sales manager for North and Mid Canterbury, has also been impressed by CALEY ® iblon ® . “After several seasons of trials, we are sure that the time to apply CALEY ® is at GS39 on both wheat and barley,” Parker advises. “We have CALEY ®

iblon ® to protect yield development in wheat, and we have to manage RLS to delay the onset of symptoms in barley.”

For further information, contact your Farmlands Technical Field Officer or the friendly team at your local Farmlands store.

Article supplied by Bayer.