Best guidance for Wheat

In some ways, from stem extension onwards a wheat plant can be thought of as an upright cylinder with a number (usually six) leaves of a similar size. If it wasn’t for the crop canopy preventing light penetration, the upper and lower leaves of the wheat plant would all contribute to yield production while ever they stayed green. However, because the crop canopy prevents significant light reaching the lower leaves it is the upper two leaves and the ear that deliver almost ninety percent of the crop's yield.

With the importance of the flag leaf to crop production it is very important to fully protect this leaf. To do this Aviator Xpro should always be applied at GS39, as soon as the flag leaf has emerged on the main tiller. This should be the start of planning your fungicide disease programme.

The next question is do I apply a second application of Aviator Xpro at GS32, to protect final leaf three from Septoria tritici infection or do I apply a second application of Aviator Xpro at GS59 to allow crop greening to be maintained, crop longevity and ultimately yield?

In 2015 Bayer Crop Science explored this question in a number of trials and what was found was that both approaches delivered very profitable yield increases. What the trials did show though was that two applications of Aviator Xpro are required for a wheat crop to deliver it's full yield potential.

However, if your crop was planted in autumn, as a guide by the 15th May, Septoria tritici could be a major problem for you. If this is the case then applying Aviator Xpro at GS32, followed by a second application at GS39, will provide excellent control of Septoria tritici.

Whatever fungicide programme you decide, Aviator Xpro applied at GS32 + GS39 or GS39 + GS59, Aviator Xpro should be applied at a dose rate of 1.0 L/ha. This will ensure maximum disease control, enhanced crop greening and long lasting leaf retention.

Before applying Aviator Xpro it is important to read the product label.

Wheat Spray Programme Arable Fungicides Bayer

Best guidance for Barley

In some ways from stem extension onwards a barley plant can be thought of as a pyramid, with large lower leaves and much smaller upper leaves. This plant structure results in a relatively thinner canopy than wheat and this, coupled with larger lower leaves, results in much of the yield production of a barley plant coming from the lower leaves and the stem. In fact, almost eighty percent of a barley crop’s yield is produced by the lower leaves and the stem.

Autumn / Winter cultivars

The recent introduction of autumn planted barley cultivars that have much larger flag leaves may start to change to the "yield map for barley". Also, the increased severity of Ramularia leaf spot in New Zealand continues. These developments have resulted in the flag leaf fungicide application for barley becoming more important.

While it is very important to protect these lower leaves, there is a difference in the optimum way to approach winter planted barley and spring planted barley.

Winter planted barley develops quite slowly until spring time but during this period it often carries a high disease loading. An application of a Delaro at this time (GS30) can be very beneficial. Not only to control disease but to allow the main GS32 fungicide application to be timed correctly.

Following the GS30 application it is important to then apply a second Delaro treatment at GS32 to protect the lower leaves and stem through to flag leaf emergence.

At GS37-45, flag leaf emergence to booting, it is very important to apply Aviator Xpro. This is the time that Ramularia leaf spot develops and unless it is adequately controlled at this growth stage very rapid green leaf loss can occur leading to significant yield loss. To control Ramularia leaf spot a SDHI fungicide has to be applied and Aviator Xpro not only applies an SDHI fungicide but does this in mixture with prothioconazole, the fungicide in Proline.

Spring barley

Spring planted barley crops develop quite rapidly and the time between GS25 (end tillering) and GS39 is consequently shorter. This means a two spray fungicide programme based on a Delaro application at GS25-30 followed by an application of Aviator Xpro at GS39 is ideal.

Bayer Fungicides Spray Programme Bayer Fungicides Spray Programme

Before applying Delaro and Aviator Xpro it is important to read the product labels.