Ensure accuracy with chemical calculations

Image: Bayer Commercial Sales Representative Paul Crack with Bayer Graduate Nina Guo at the Southern Farming Systems Field Day, Inverleigh, Victoria.

There has been some confusion over the cost calculations of some chemical products, particularly where they are used in different crops and at different application rates.

Aviator^® Xpro^® is a relatively new fungicide initially registered for use in canola and some pulse crops and more recently registered for use in wheat, barley and a wider range of pulse crops.

Due to its unique chemistry, Aviator Xpro is providing industry leading disease control in these crops, as well as an alternate mode of action for resistance management, however its application rate and associated per hectare cost in the different crops varies considerably.

Developed by Bayer, Aviator Xpro contains bixafen, a novel member of the Group 7 (SDHI) fungicides, as well as the proven performance of the Group 3 (DMI) fungicide, prothioconazole.

It has shown strong control of various diseases in pulse crops and blackleg and sclerotinia diseases in canola, while it also controls septoria tritici, eyespot, stripe rust, yellow leaf spot, septoria nodorum and powdery mildew in wheat, as well as net form net blotch, spot form net blotch, leaf rust, powdery mildew and leaf scald in barley.

More widely known as a result of its longer term use in canola, Aviator Xpro has a recommended application rate of 550-800 mL/ha in canola, costing from about $30/ha (at 550 mL/ha). The label rate range in pulse crops is 400-600 mL/ha.

However, in wheat and barley, the recommended application rate is 300-500 mL/ha, costing from around $16/ha (at 300 mL/ha).

For diseases like septoria tritici, which was a concern in a number of wheat growing areas last season, this compared well with other fungicide options including Tazer® Xpert™, Radial® and Veritas®.

Bayer Commercial Sales Representative Paul Crack said septoria tritici was a major factor across large areas of western Victoria last year and trials conducted by Southern Farming Systems at Westmere in 2016 and 2017 showed improved final grain yields with Aviator Xpro compared with Radial.

“At the higher application rates applied twice in the season, Aviator Xpro achieved a 7% yield increase and cost around $1/ha less than Radial,’’ Paul said.

He said control of septoria tritici in crops would be critical again this year, also to help manage the disease in stubbles and limit any summer carryover into 2020 crops.

“Applications this season are also about reducing carryover for the following year to help keep the disease under control.’’

“Growers typically apply Aviator Xpro at 300 mL/ha, but in high pressure situations and where there has been a lot of rainfall, going to 500 mL/ha will provide greater protection.’’

Aviator Xpro also offers good compatibility and its patented LeafShield™ formulation technology enhances its activity against diseases. It has a short rain-fast period, estimated at around 30 minutes to one hour in most situations, which is particularly beneficial in high rainfall environments.