Rick Llewellyn1, Sam Kleeman2, Chris Preston2, Therese McBeath1, Navneet Aggarwal1, Bill Davoren1, Vadakattu Gupta1, Gurjeet Gill2, Willie Shoobridge1, Stasia Kroker1, Marcus Hicks1
1CSIRO and 2University of Adelaide, Waite Campus, Glen Osmond, South Australia, 5064
- Substantially better brome control and seed set reduction is possible by using pre-emergence options other than trifluralin.
- The costly Sakura+Avadex treatment is likely to be the most effective.
- Consistency of performance of all pre-emergence herbicides for brome remains a problem
- On-row seeding on non-wetting sand showed that it can substantially improve early crop emergence.
- One reason for this is the likely wetter surface soil in rows at time of seeding.
- Seasonal conditions such as the long-wet season of 2016 will affect efficacy of both pre-emergence herbicides and the impact of additional crop competition on brome seed set suppression.
- Maintaining low seedbanks and having alternative options for weed seed control when faced with a risk of ‘blowouts’ in brome seed set is important given the chance of particularly poor control in some seasons.
How was the trial done?
Trials in 2015 were conducted separately on seeding position and pre-emergence herbicide efficacy on brome grass. In 2016 interactions between pre-emergence herbicide options and crop row placement were investigated. Field experiments were conducted on Mallee sand in Karoonda in South Australia during 2015 and included a range of pre-emergence herbicide treatments on Kord wheat. In 2016 a range of pre- and early post- emergent herbicide options were tested in combination with on-row or inter-row seeding. One trial tested more standard pre-emergence options while a nearby trial compared higher trifluralin rates with higher cost Avadex-based treatments.
This work was funded under the GRDC Stubble Initiative in partnership with MSF and CSIRO. Thanks to site hosts Peter and Hannah Loller and Damian Mowat for additional technical support and input from Jeff Braun and Michael Moodie.