Australia
July 9, 2015

Life

1. Give everything you’ve got
2. Repeat daily

Glyphosate resistant awnless barnyard grass

1. High glyphosate rate
2. Small plants
3. Low temperature (if possible)
4. Double knock when it’s hot

Annual ryegrass is Australia’s glyphosate resistance champion.

The runner up is awnless barnyard grass (in terms of the number of populations). 

Glyphosate resistance was first confirmed in awnless barnyard grass in 2007 in northern NSW, and it has gone gangbusters ever since.

AHRI researcher Heping Han recently teamed up with Michael Widderick (QDAF) to learn a little more about this weed. They discovered that the mechanism for resistance is the Proline 106 mutation. 

On its own, this mutation gives about 4 fold resistance in ryegrass. In this study it only resulted in 2.5 fold resistance in awnless barnyard grass. 

With this low level resistance, the researchers found that label rates of glyphosate still worked when temperatures were cool, but glyphosate failed dismally when it got hot.

READ MORE

P.S. Over the next few months, we're showcasing the Ryegrass Integrated Management (RIM) model. Find out what RIM can do with our easy-to-digest, done-for-you output from RIM. It only takes a couple of minutes! Click here or follow the link below for newest run. 

Website: http://www.ahri.uwa.edu.au/

Published: July 9, 2015