Researchers develop a way to control 'superweed'

They pop up in farm fields across 22 states, and they've been called the single largest threat to production agriculture that farmers have ever seen. They are "superweeds" – undesirable plants that can tolerate multiple herbicides, including the popular gylphosate, also known as RoundUp – and they cost time and money because the only real solution is for farmers to plow them out of the field before they suffocate corn, soybeans or cotton. Now, thanks to the work of researchers at Dow AgroSciences, LLC, who have been collaborating with a University of Missouri researcher, a new weapon may be on the horizon to eliminate superweeds.

Zhanyuan Zhang, a research associate professor of plant sciences and director of the MU Plant Transformation Core facility, partnered with research scientists at Dow AgroSciences, LLC, to engineer soybean plants that can tolerate an alternative herbicide that may help slow the spread of superweeds, such as tall waterhemp.

According to an article in the May 3 edition of the New York Times, farmers considered RoundUp a "miracle chemical" when it was introduced because it killed a wide variety of weeds, is safe to work with, and broke down quickly, reducing environmental impact. However, weeds quickly evolved to survive gylphosate, and that threatened to reverse an agricultural advance known as minimum-till farming. As the superweeds survive in the fields, farmers must spend more time to get rid of them, even going so far as pulling the weeds by hand. The Times noted that there were 10 resistant species in at least 22 states infesting millions of acres of farmland.

Using a massive genetic database and a bioinformatic approach, Dow AgroSciences researchers identified two bacterial enzymes that, when transformed into plants, conferred resistance to an herbicide called "2,4-D," commonly used in controlling dandelions. The enzymes were successfully put into corn and soybean plants, and those new plants showed excellent resistance to 2,4-D, including no negative effects on yield or other agronomic traits. Other advantages of 2,4-D include low cost, short environmental persistence, and low toxicity to humans and wildlife.

"Unlike glyphosate, which targets amino acid synthesis, 2,4-D is a hormone regulator. Because it has a different mode of action, 2,4-D is an ideal herbicide to deal with glyphosate-resistant weeds," said Zhang, who managed the soybean transformation portion of the study and contributed to some data analysis.

Zhang believes that 2,4-D could eventually be combined with other herbicides in the near future. In the meantime, Zhang says an integrated weed management plan can help farmers be productive and ultimately save money for the consumer.

"The less chemicals use in the field, the less money they spend on production," said Zhang. "That leads to less cost for the consumer, as well as improved food safety and environmental safety."

Explore further

Herbicide diversity needed to keep Roundup effective

More information: Study results were published in the November issue of The Proceedings of the National Academy of Sciences.
Citation: Researchers develop a way to control 'superweed' (2011, January 21) retrieved 15 October 2019 from
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Jan 21, 2011
[quote]Now, thanks to the work of researchers at Dow AgroSciences, LLC, who have been collaborating with a University of Missouri researcher[/quote]

Wait a second. Are you telling me that Missouri tax money is going to fund Dow Corporation research? Will the Missouri taxpayer and farmer see a benefit or is that an externality?

Jan 21, 2011
And, 2,4D is not as benevolent a substance as it is being made to sound here in this press release. Basically what thet're saying is that they want to spray millions of acres with a substance which is a somewhat-less-virulent component of Agent Orange.

Jan 22, 2011
These spammers are getting more and more brazen, really starting to annoy me. Physorg, it should be really easy to filter them out, a typical spammer produces nearly identical messages regardless of the article, that should be enough.

Jan 22, 2011
Just what we need, more and better herbicides and plants that we eat that tolerate them, what about OUR tolerance for the herbicides?

This spammer could be easily filtered just by a couple words. Who uses polo t-shirt in a post? Better yet, filter with a spell check. It would weed him out as well as some other people, this guy couldn't spell correctly even with the spell check highlighter. Quality is our dignity?

Jan 22, 2011
Does this sound to anyone like the start of the same cycle as antibiotics? I don't like the entire approach of taking a food crop and making it less sensitive to an herbicide with its "low toxicity to humans". Isn't there a way to genetically alter the weed or its pollen?

Jan 22, 2011
We're farmers, and you know what...the next time you go to the grocery, and find that some of the items you were able to afford, are somehow just getting out of hand in the price zone...think abouk how desperately weed control is needed to put food on your table. Because of the weeds, we will be charging more, amd making 150% LESS than you actually pay at the marke thanks to all the hands our product filters through.Please help us find the right way to fight the problem, and make sure you do not complain with your mouth full.

Jan 22, 2011
Why not just burn the motherfuckers?

Jan 23, 2011
@ BubbiesMom:
My mouth is full of an organically-grown carrot, and with all due respect, as your work is essential to existence, I would implore you to switch over to organic farming methods. Dow Chemical manufactured napalm that was used to burn Vietnamese and Cambodian
children alive, so boycott anything they sell. You shouldn't expose yourself and family to any of this toxicity, or me, your customer. I'll gladly pay the higher price for your produce, instead of the price for Cisplatin.

Jan 23, 2011
There were numerous errors in this article. First of all an error made in the New York Times should have been referenced. Glyphosate is not environmentally friendly as Monsanto found out in European courts. They lied about that fact. It remains in the soil for years and is responsible for a lot of health issues to people using it and those living near to where it is used.
Second bone of contention there is no way that 2,4-D is safe. As it says in the article 2,4-D is a hormone regulator. Say hello to more birth defects. If you doubt it ask the troops from the Vietnam war. Ask the people still living out there.
In all this article there has not been one mention of the fact that like anti-biotic resistance in bacteria we are creating the self same situation in the plant kingdom.
One poster Telekinetic, spoke the truth. I don't want to eat chemical industry crap and I certainly don't intend to poison my environment or allow it to be poisoned just so some chemical company can profit.

Jan 24, 2011
Superweed?! Oh, I see, cancel the Twinkies.

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