Did you know that rotary hoeing requires less energy than steaming? Or that offset discing requires less energy than microwaving? Well, that’s the case when it comes to controlling weeds. An epic effort to review 170 papers by a team from the University of Sydney (Guy Coleman et al) has shown that mechanical weed control options (eg. tillage) can use significantly less energy than thermal options (eg. heat) to kill weeds. Herbicide energy use sits somewhere in the middle.
Tag Archives | herbicide resistance
Roberto recently completed a project with GRDC investment where he sampled ryegrass from 17 paddocks across eight farms in Western Australia to see if there are benefits of proactively testing for herbicide resistance. Across these tests, he found ryegrass that was resistant to Clethodim (Select) or Butroxydim (Factor) but no ryegrass that was resistant to the mix of the two. The same went for the pre-emergent herbicides as well, no resistance to mixes.
Charles Sturt University has sown, sprayed and counted annual ryegrass from around 12 million seeds submitted from more than 5000 samples sent in from across Australia since it started testing for herbicide resistance in 1991…and that’s just ryegrass. Mind numbing stuff. But more than 5000 ryegrass samples? Most tested to five or six herbicides? Think about the value of that information! Dr John Broster and Professor Jim Pratley from CSU have analysed the data from ryegrass samples sent to the testing service over the 25 year period from 1991 to 2015.
We once thought that the genetics of eye colour was simple. Both parents have blue eyes, therefore, all of their children will have blue eyes. Easy peasy! Then science progressed and we realised that it isn’t actually that simple because several genes are involved. The genetics of herbicide resistance was simple. One parent is resistant to a herbicide, therefore, all of the offspring will be resistant because the gene is dominant or semi-dominant. This is true for almost all cases of herbicide resistance and was easy to understand. Until now. Click to read more about PhD student Jinyi Chen’s research.
Wine and cheese. Strawberries and cream. Crop competition and pre-emergent herbicides. Ok so the last one doesn’t quite have the same ring about it but they really do go together nicely. Combining a competitive canola variety with pre-emergent herbicides has proven to be an effective strategy for reducing annual ryegrass seed set. Recent trials showed that with effective pre-emergent herbicides, a competitive hybrid canola variety can reduce ryegrass seed set by 50% compared with a less competitive open-pollinated (OP) variety. That’s impressive. But should we tar all OP varieties with the same brush?
There are few herbicide options for sowthistle control in chickpea crops, making the perfect recipe for a good ol’ sowthistle blowout. Despite all of this, the latest research by Michael Widderick, Adam McKiernan and Greg Harvey from QDAF with GRDC investment is finding that chickpeas can win the competition against sowthistle if they stack their deck. Growing a chickpea crop at narrow row spacing and high crop density in northern cropping regions can greatly reduce sowthistle seed production without reducing chickpea yield. Click through to find out more!
Do you know what a microtubule is? If you could dream up the most complex way to make a tube, microtubules are it! Assembling a microtubule is about as complex as assembling a car, and there are thousands of them in every cell, in every living thing. If you aren’t super interested in the detail, all you need to know is that trifluralin kills plants by binding to microtubules and stopping cell division. AHRI researcher Qin Yu and her team of Chinese PhD students have recently identified the exact mutation in microtubules that stops trifluralin binding to them and causes…
Jonah Lomu stood at 6’5”, weighed 120kg, and ran the 100m in a lazy 10.7 seconds. He could play the power game, the speed game, and he could step. He was the ultimate competitor. Mace wheat, on the other hand, is agile, dependable, and can play the yield game, but its ability to compete with weeds is limited. However, yield is king, and hence Mace has been an extremely successful variety where weeds are under adequate control. What if we could have a wheat variety that could play the yield game and the competition game? What would that look like?
Did you ever receive a present as a child on Christmas Day only to have it broken on Boxing Day? I was devastated when my cousin bit the head off my GI Joe action doll at the family BBQ. I thought Joe would be tougher than that!
Feathertop Rhodes (FTR) Grass is the boy band of the weeds world. They pop up quickly from obscurity (first to germinate after rain), stress easily at the first sign of trouble (dry), and can be all done and dusted in 18 months (short seed life), not to mention that they are downright annoying as well! If you think this is just a Queensland problem, think again. This boy band, I mean weed, has risen to fame in recent years as it has spread from its home in Queensland to playing gigs on road verges all over the country. When faced…