The NSW Department of Primary Industries work has identified the DNA barcodes for the two weeds, making it easier to distinguish them from native grasses in eastern Australia.

NSW DPI scientist, David Gopurenko says for the first time researchers now have the potential to develop a timely and easy way to distinguish between invasive and native grasses at early growth stages.

“DNA barcoding gives us the opportunity to shortcut the traditional identification process, which usually requires examination of the plants’ flowers, which can only take place once the plant has reached maturity,” Dr Gopurenko said.

“Now we have the ability to better manage new incursions by identifying weeds before they mature, flower and become established,” he said.

DNA barcoding can accurately identify species from small samples, including trace amounts of degraded tissue which has not been stored properly.

Correct identification of invasive and native grasses is crucial in weed management as misidentification can delay control of invasive weeds and could also lead to the unwanted eradication of desirable native grass.

Native to South America, serrated tussock and Chilean needle grass cause significant damage to the Australian environment and agricultural industries.

Serrated tussock costs more than $40 million in lost production each year, covering more than 1.1 million hectares, with more than 30 million hectares of south-eastern Australia classed as climatically suitable for the weed’s invasion.

Annual costs of Chilean needle grass exceed $120 per hectare.

The three-year study to identify the DNA barcodes of invasive weeds was funded by the NSW Weeds Action Program led by NSW DPI scientists, Aisuo Wang, David Gopurenko and Hanwen Wu, all based at the Wagga Wagga Agricultural Institute. 

A new project to develop a field-based tool to identify Chilean needle grass and serrated tussock using the DNA barcodes has this year been funded through the Australian Government’s Agricultural Competitiveness White Paper.