Glyphosate resistance in SW Victoria. In 100 ryegrass samples collected in 2019 as part of GRDC random weed survey, 40% showing Glyphosate resistance vs 4% in 2014 survey. Very concerning! @GRDCSouth @Phil_WesternAG @AParidaen @WeedSmartAU
Photo of glyphosate knock-down effect of susceptible ryegrass with ammonium-sulphate. Indicates that AMS does more than condition water. All pots treated with a sub-lethal rate (125g ai/ha) Glyphosate 540. Right=2% AMS, middle=0.2% wetter, left=herbicide only.