A new herbicide from FMC, an Agricultural Sciences Company, is under review by the APVMA and has been attracting attention at field days throughout Australia in recent months.
Overwatch® Herbicide is anticipated for commercial release in 2021 and is expected to be a new pre-emergent option to control Annual ryegrass and a wide range of other weeds. Replicated field trials show that the attributes of the chemistry in Wheat, Barley and Canola may also maximise yield potential and provide flexibility with crop choice, replants and rotations.
FMC Herbicide Portfolio Manager, Hugh Palmer said, “Feedback has been very positive from farmers and agronomists who have seen Overwatch® Herbicide in trials. Once registered, this product is expected to be available for use in several crops and, as a Group Q (proposed) molecule, will be very different from what is currently available in the broadacre herbicide market.”
“The mode of action means it will control Annual ryegrass and herbicide resistant biotypes. This will provide a new option in many parts of Australia where some current herbicides are losing their effectiveness,” Mr. Palmer said. “By utilising Overwatch® Herbicide in the rotation, trial results are confirming that this molecule effectively controls resistant weed types and will potentially extend the life of other herbicide options.”
“One of the unique features of the herbicide can be seen in the way the Ryegrass reacts to the chemical,” Mr. Palmer said. “The Ryegrass turns a striking shade of magenta which is noticeable through the rows before turning white, and eventually disappearing. Overwatch® Herbicide has demonstrated long-lasting residual control, so we have seen its effectiveness on later germinating weeds.”
The new herbicide will be applied as an IBS (Incorporated By Sowing) treatment and has demonstrated excellent performance across a wide range of locations and conditions this season and in replicated field trials over several years.
Mr. Palmer said Overwatch® Herbicide is proving to be a robust herbicide which has controlled weeds in both wet and dry conditions, and in trials with high stubble loads. “Parts of Victoria, for instance, have had large amounts of rainfall while other areas such as New South Wales have struggled. In all cases, trials with Overwatch® Herbicide have shown excellent efficacy,” he said.
The 2019 field and demonstration trials compared the performance of Overwatch® Herbicide to a wide range of current herbicide options and untreated plots. “There are some sites with very high Ryegrass pressure,” Mr Palmer said. “The untreated sections resembled a golf course with the grasses coming through. We are happy to report Overwatch® Herbicide has been very effective.”
He explained that while Ryegrass is the major weed being targeted with this chemistry, agronomists are also excited by the range of region-specific weeds that Overwatch® Herbicide appears to control. “Weeds such as Wild oats, Charlock and Wireweed are expected to be on the label pending APVMA approval, and we continue to see good control of other species. Work will continue to identify and evaluate other weeds to be added to the label going forward.”
Mr. Palmer said growers and agronomists should be aware that there could be instances of crop discolouration when Overwatch® Herbicide is used. “Concentrated doses of herbicide have been shown to cause a lightening of the leaf area in the time after emergence,” he said. “The crops in our trials have continued to grow through this and within a few weeks they returned to normal and have shown no lasting effect on growth or yield.”
Overwatch® Herbicide is currently pending approval by the APVMA and registration is anticipated in 2020, with the full launch and good volumes of product in 2021.
“There were numerous trial sites throughout Australia this season, with additional sites planned in 2020,” Mr Palmer indicated. “I would encourage agronomists and growers to get in touch with their local FMC representative to have a look at the performance of this unique herbicide and how suited it will be for current farming practices.”
FMC Herbicide Product Manager, Hugh Palmer inspecting a wheat trial at Temora, NSW where O Overwatch® Herbicide demonstrated excellent control of Ryegrass.
The unique features of O Overwatch® Herbicide which briefly turns the Ryegrass a striking magenta colour.