Grain growers in Victoria, South Australia and Tasmania who detect weeds that have survived herbicide applications are encouraged to have those weeds tested in-season for herbicide resistance.
Research scientist Peter Boutsalis said screening of weeds during the winter crop growing season provided growers with valuable information on the effectiveness of herbicides on target weeds.
A 'Quick Test' - the only in-season test of its kind in which plants (grasses and some broadleaf weeds) are tested for herbicide resistance (or susceptibility) - can assist growers in understanding the extent of resistance on their properties.
"The Quick Test works on plants from seedlings to advanced tillering, as long as the plants are green and healthy," Dr Boutsalis said
"The test usually takes about four weeks to complete, provided the weeds received are in good condition."
University of Adelaide and Plant Science Consulting Dr Boutsalis said it was important to provide accurate details about the location from which weeds were collected for sampling during registration for the test.
Information about the Quick Test service, including a video on how to prepare and send samples for testing, is available on the Plant Science Consulting website at plantscienceconsulting.com.au/weed-resistance-quick-test/.
Annual resistance surveys conducted by Dr Boutsalis and his colleagues through a GRDC research investment have shown concerning levels of herbicide resistance in some weed species in many parts of the southern cropping region.
"The surveys provide resistance status information on a regional basis, informing growers' integrated weed management strategies," Dr Boutsalis said.
"In-season testing of weeds that growers suspect are resistant adds another layer of knowledge to support growers in combating the spread of resistance and extending of the longevity of existing chemistries, and the employment of effective chemical and non-chemical weed control tactics."
See more at grdc.com.au/IWMhub and weedsmart.org.au.