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Australian Herbicide Resistance Initiative (AHRI)

AHRI insight – the 100 is up!

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Australian Herbicide Resistance Initiative (AHRI)

AHRI insight – the 100 is up!

We’re undecided whether we should picture the AHRI communication team cutting through a massive banner as we run onto the ground or raising our bats in the air at the MCG after a long day in the middle. It’s been a long innings and is one that we have enjoyed immensely. To celebrate the 100th AHRI insight we’re reflecting on what have been the big stories that got you excited and made the biggest impact.

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Australian Herbicide Resistance Initiative (AHRI)

How trifluralin resistance works

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…

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Heping Han

Australian Herbicide Resistance Initiative (AHRI)

Glyphosate resistance and plant fitness

Things that affect your fitness: Christmas – go on, have one more serving of trifle, it is only wafer thin! Television – for example, spending five full days watching the Boxing Day test match cricket. Each on their own are not too bad, but put them together and we have a problem. Things that affect plant fitness: The TIPS mutation that causes high-level glyphosate resistance. The TIPS mutation is a double mutation of the glyphosate target site, the 102 and the 106 mutation. The 106 mutation has been found in a number of species and has no fitness penalty associated…

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Australian Herbicide Resistance Initiative (AHRI)

Selfish weeds can manipulate the nitrogen cycle to suit themselves

Weeds are selfish, self-centred, narcissistic, manipulative pieces of work that will do whatever it takes to make themselves look good and make the other plants around them look bad. Some weeds are so self-obsessed that they can manipulate the soil nitrogen into a form that is just the way they like it. New research by Cathryn O’Sullivan from CSIRO is showing that some weeds release chemicals from their roots that slow down the bacteria that are essential to the nitrogen cycle, retaining nitrogen in the ammonium form that weeds can potentially take up faster than crop plants. Totally selfish! Click…

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Australian Herbicide Resistance Initiative (AHRI)

Sowthistle – know the enemy, exploit its weakness

Going into the 1932-33 Ashes tour in Australia, Don Bradman was averaging around 100, and he had averaged 139 in the 1930 tour of England. He seemed unbeatable. How then, did he go on to only averaging a paltry 56.57 in 1932-33 Ashes? Simple, the English cricket team had discovered his weakness, short, fast, leg side bowling known as bodyline, and they employed this tactic much to the chagrin of the Australian public. ‘It’s just not cricket!’ When we are faced with a new enemy, that is seemingly unbeatable, we need to investigate its weaknesses and then perhaps we can…

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Australian Herbicide Resistance Initiative (AHRI)

Microbial degradation of propyzamide – will we have a problem?

Some excellent research conducted by Stephen Hole, under the watchful eye of Professor Steve Powles at the University of Adelaide in the mid-1990’s investigated the microbial degradation of propyzamide and another similar herbicide, carbetamide. Enhanced microbial degradation is where the soil bacteria that can eat a particular herbicide build up to very high levels so when the herbicide is applied it is broken down very quickly, effectively reducing the half-life of the herbicide.

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Australian Herbicide Resistance Initiative (AHRI)

Glufosinate resistance – we know what it’s not

“There are known knowns; there are things we know we know. We also know there are known unknowns; that is to say, we know there are some things we do not know. But there are also unknown unknowns – the ones we don’t know we don’t know. And if one looks throughout the history of our country and other free countries, it is the latter category that tends to be the difficult ones,” Donald Rumsfeld, US Secretary of Defense 2001-2006. Man, that’s deep! It’s wonderful for a scientist to have a hypothesis, do the research, and find that they were…

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Australian Herbicide Resistance Initiative (AHRI)

Wild oat resistance takes effort

Many young people don’t like the taste of beer, but they know if they work hard, endure the awful bitter taste and hideous hangovers for a few years, they will eventually like the stuff. It takes effort, but if they stick at it long enough they can get there. And, believe it or not, you have to work pretty hard to evolve resistance in wild oats. But if you stick at the same practice long enough (it takes effort), you can get there! We have previously reported AHRI research showing that wild oats evolve resistance slowly because they are both…

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Australian Herbicide Resistance Initiative (AHRI)

How stuff works: 2,4-D, free radicals and monkeys

It’s pretty amazing that 2,4-D is our oldest herbicide, yet scientists have only just worked out how it actually kills weeds. This has taken years of research by many researchers to understand. So, like the monkey Curious George, we set out to understand how 2,4-D works (trust us, click through to the full post and the monkey analogy will make sense!) 2,4-D works in three stages: first, it over-stimulates plant growth; second it closes the stomata and shuts down photosynthesis. And finally, the plant eventually starves to death as it works hard to detoxify the free radicals. In a nutshell:…

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Australian Herbicide Resistance Initiative (AHRI)

2,4-D Gridlock

Picture yourself as a city slicker driving to work. Between your house and the freeway there are four sets of traffic lights. On this particular day all of the traffic lights are stuck on red. The city is in chaos with no-one able to get to work. You then spend the rest of your life, in your car, at a red traffic light. Perish the thought! This is how 2,4-D resistance works in wild radish. The traffic lights are transporters that allow 2,4-D to move from cell to cell, and the freeway is the phloem – the plant veins that…

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