Bernie Quade (Landmark)
|Contributor||North East Farming Futures|
Northern Ag region of Western Australia, WA
To investigate alternative modes of action for the control of very low populations of ryegrass and wild radish when using a spot spraying technique during spring on spray fallow paddocks. The purpose of exploring alternative modes of action is to help prevent the onset of glyphosate resistance because the spray fallow technique is a high risk method from a resistance perspective.
In this trial, even the conditions at the time of spraying were ideal (high humidity), Basta (group N) performed poorly on both radish and ryegrass. The group G products did not seem to provide significant additional control over and above its mixing partner. Better treatments included 4L of glyphosate (not an option from a resistance management perspective), Sprayseed + Atrazine as well as 8L of Alliance. There was a clear rate response in wild radish control with Alliance when moving from 6L to the 8L rate. Even though a high rate (and therefore cost) of Alliance is required it is a viable option because it combines group L and Q chemistry. The active ingredient amitrole (group Q), also appears to have useful activity on ryegrass at these rates.
The treatment of Sprayseed + Atrazine appeared quite effective but it would come with a caution as the 2kg of Atrazine could pose a carryover risk (only on sprayed areas) if planting a non TT tolerant crop the following year in the absence of adequate rainfall.
The lack of treatments that gave 100% control of the target weeds illustrates how dependant this system is on glyphosate, and how vulnerable the system is if we encounter a high frequency of glyphosate resistant weeds in these paddocks.
|Lead research organisation||
North East Farming Futures
|Host research organisation||N/A|
|Other trial partners||Not specified|
|Sow date||Not specified|
|Harvest date||Not specified|
|Plot size||Not specified|
|Plot replication||Not specified|
SILO weather estimates sourced from https://www.longpaddock.qld.gov.au/silo/
Jeffrey, S.J., Carter, J.O., Moodie, K.B. and Beswick, A.R. (2001). Using spatial interpolation to construct a comprehensive archive of Australian climate data , Environmental Modelling and Software, Vol 16/4, pp 309-330. DOI: 10.1016/S1364-8152(01)00008-1.