Flexible new herbicide partner improves weed control, resistance management

SOUTH Australian cereal growers have an opportunity to improve control of their specific broadleaf weed populations this season, including herbicide resistant weeds.

This addition to herbicide armouries could even help manage the typical two-spray strategy employed against challenging broadleaf weeds, which, amid concerns over diesel supply and cost, would be highly valuable this year.

Marathon, developed by ADAMA Australia, is a high-load solo pyrasulfotole herbicide with an in-built crop safener that, when mixed with other post-emergent herbicides, offers “superior” weed control, while providing good crop safety.

Growers will have the flexibility to apply it with a wide range of herbicides to control more weeds and help improve herbicide resistance management.

Marathon comprises 230g/L of the group 27 pyrasulfotole herbicide and provides particularly robust control of wild radish, wild turnip and Indian hedge mustard, plus sow thistle, Paterson’s curse, prickly lettuce, climbing buckwheat, bifora, deadnettle and others.

Applied from the two-leaf crop stage, depending upon the tank-mix partner, it incorporates unique, patent-pending formulation technology that enhances its solubility, stability and performance under diverse environmental conditions.
ADAMA Australia herbicides portfolio manager Rob Walker said the unique, stable, efficient and highly concentrated liquid formulation prevented crystallisation that could occur with other pyrasulfotole herbicides under certain conditions.

Market development manager Bevan Addison said several formulations were tested during the development phase before selecting Marathon for its performance, excellent stability and unique formulation trait.

“We also deliberately chose a formulation with added crop safener for grower and adviser peace of mind with all tank-mix partner options, offering strong performance while ensuring crop safety,” Bevan said.

He said Marathon would allow growers great flexibility to customise their applications based on their weed spectrum and burden, as well as herbicide resistance status, which was always a focus with weeds like radish.

Rob said other co-formulation herbicides can apply a high rate of pyrasulfotole that may be unrequired.

“With Marathon, growers and advisers can tailor the pyrasulfotole rate and fully customise tank mixes with an extensive range of ADAMA post-emergent herbicide options to broaden the weed spectrum controlled,” he said.

“The solo pyrasulfotole offers strong flexibility with tank mix options, it’s a good formulation, it’s highly competitive compared with other similar herbicides, and the group 27 mode of action is excellent for resistance management.

“Marathon enables a cost-effective spike by introducing a Group 27 mode of action to current spray programs.”

Bevan said independent surveys suggested including more modes of action into spray applications would be effective to achieve better outcomes against herbicide-resistant weeds.

“The long-term control could mean growers may not need a two-spray strategy, but even if they do, it will be so much delayed that they will have plenty of flexibility,” he said.

Development trials have been carried out across the country since 2021 prior to the introduction of Marathon.

“It has been in our trials throughout Australia, incorporating different weed spectrums and difficult-to-control weeds like radish in Western Australia and South Australia, and it has performed well everywhere,” Bevan said.

“Its knockdown effect is comparable with common pyrasulfotole brews that are used, and then with Marathon and novel mix partners you get the residual control.”

He said all major reseller groups and many consultants and farmers had seen the trials and acknowledged the performance of the Marathon tank mixes.

“They have clearly seen it working and understand the flexibility the product offers, allowing growers to tailor their applications to the particular weed challenges they face.”

Bevan said early interest in the Marathon tank-mix partner for applications this upcoming season already was strong.