Don’t miss the last chance to protect your cereal crops

For most arable areas in New Zealand the next three to four week period offers the last chance to apply fungicides. After mid-December most cereal crops will be at a growth stage where applying fungicides may not deliver a worthwhile return. At this time of year the focus of any fungicide application is two key targets – controlling late season flag leaf and ear disease in wheat and flag leaf disease control in spring barley crops.

Wheat Leaf Rust
Sooty Moulds

Wheat disease control

Often the most  important aspect of late season fungicide applications in wheat is that it allows the continued protection of the flag leaf, especially from attack by leaf rust and tan spot.

Reports are now coming in of Septoria leaf blotch infections developing. If Septoria is not yet established on the flag leaf then infection will also be reduced by fungicide application.

Even in dry seasons, continued flag leaf protection is worthwhile because it is now a recognised fact that certain fungicides, eg, Prosaro and Aviator Xpro, can reduce the impact of stress, which in turn leads to increased yields.

Wheat can be attacked by a number of ear diseases at this time. The key ones to look out for on the ear are sooty moulds, Fusarium species, Microdochium (now called Monographella nivalis) and glume blotch.

Ear diseases not only look unsightly but infection often results in discoloured, shrivelled grain which is much lower value and difficult to sell.

To ensure effective disease control, apply Prosaro at 1.0 L/ha in mixture with an appropriate strobilurin fungicide, or alternatively apply Aviator Xpro at 1.0 L/ha. Both these fungicides will ensure your wheat crops reach the maximum potential this season.

Protect your cereal crops
Protect your cereal crops

Spring barley disease control

Many spring planted barley crops will now be at flag leaf emergence, the ideal time to ensure that Ramaularia leaf spot is effectively controlled.

Ramularia symptoms, which manifest as brown spots that then coalesce into larger brown lesions, are triggered by stress factors such as high light intensity and drought. Once Ramularia develops it can progress rapidly leading to extensive loss of green leaf area.

To control Ramularia, leaf rust and any late scald and net blotch infections, apply Aviator Xpro at 1.0 L/ha at flag leaf emergence.

Trials carried out by Bayer in Canterbury have shown that applying a fungicide at flag leaf emergence, rather than waiting to the traditional toothbrush time, gives more effective Ramularia control.