Barley Spray Programme - Diseases

The two programmes below are designed to provide robust control of scald, net blotch and leaf rust. They will also aid with the management of ramularia leaf spot delaying the onset of disease. Visit the pest pages to learn more.

The main difference between the programmes illustrated above is the choice of iblon formulation applied at GS39.

VIMOY iblon is a solo formulation of a powerful, SDHI fungicide called isoflucypram, or ISY for short. Designed to be used in mixture with a partner DMI fungicide, the addition of Prosaro is ideal.

CALEY iblon is a ready mixed co-formulation of SDHI + DMI fungicide. In this case isoflucypram plus prothioconazole and is designed to control scald, net blotch and leaf rust, and aid the management of ramularia leaf spot, in a convenient, ease-of-use manner.

Delaro is used in the programmes to provide excellent early season disease control, primarily of scald and net blotch, but also of any leaf rust present. As a co-formulated mixture of a DMI fungicide (prothioconazole), plus strobilurin fungicide (trifloxystrobin), Delaro is easy-to-use, convenient and applies an additional fungicide mode-of-action.

Please note the addition of Folpet (Phoenix®) at both GS32 and GS39. In trials carried out by Bayer in both Manawatu and Canterbury the addition of Folpet has aided the management of ramularia leaf spot.

Key points

• It is important to maintain a spray interval of between 25-28 days between fungicide applications. If the interval is greater than 28 days disease control will be compromised.
• The use of SDHI fungicides is limited to 2 on any cereal crop. These programmes only apply a single SDHI fungicide and so can be applied even if a SDHI seed treatment has been used.
• The structure of most barley varieties is such that the larger lower leaves and the stem account for the majority of the crop’s yield. Therefore, applying a robust fungicide at GS32, and also at GS30 if disease develops during late winter, is very important.
• The GS39 fungicide remains important even though much of the crop’s yield has already been developed. It keeps the plant healthy and reduces stress, the trigger for ramularia leaf spot.

This programme applies an additional SDHI fungicide, CALEY iblon, at GS55 (full ear emergence). This is designed to retain maximum green leaf area and is targeted at high yielding crops under irrigation.

Please note only two applications of a SDHI fungicide or of Folpet should be used in a fungicide programme.

While spring planted barley crops have a shorter growing period than those planted in the winter they are still likely to be attacked by disease. While all barley diseases remain a threat, the biggest threat usually comes from scald and leaf rust.

A programme based on Delaro plus Folpet at GS30-31 and Aviator Xpro applied 25-28 days later at GS37-45 is ideal. Providing robust control of all key diseases at a cost suited to a short season crop.

Although not illustrated on the spray programme, if you have a late winter planted barley crop and it develops disease around the end tillering, the application of Proline can be very beneficial.