Just a few years ago, herbicide resistance in weeds was something that seemed like a distant concern, something occurring elsewhere; however, it should be no surprise to anyone that today the International Survey of Herbicide-Resistant Weeds, which is a collaborative effort between weed scientists in more than 80 countries, says that is no longer true.
According to AGCO, self-priming, recirculating booms and product-recovery systems aid in the prevention of herbicide-resistant weeds as a fully primed boom provides better herbicide coverage and less weed escapes.
It reports there are currently 514 unique cases (species x site of action) of herbicide-resistant weeds globally, including 262 species (152 dicots and 110 monocots). Overall, there are now documented cases of weeds developing resistance to 23 of the 26 known herbicide sites of action and to 167 different herbicides.
The problem is no longer an isolated one. Herbicide-resistant weeds have been reported in 93 crops in 70 countries. Canada is no exception. The organization reports 68 known cases of weed resistance here and 165 south of the border in the United States.
Therefore, it’s something Prairie producers need to keep in mind. And at least one equipment manufacturer, AGCO, has been in the field demonstrating how the technology included on their sprayers (and some others) can help prevent — or at least slow — the problem from getting worse. AGCO has made sprayer demonstrations part of its Application Crop Tour program this year.
“We’re living in a world where weed resistance to herbicides is becoming a bigger and bigger issue, and we don’t want to exacerbate it by poorly applying herbicides,” said Darren Goebel, AGCO director of global agronomy and farm solutions, in a press release. “We’re really thinking about how spraying equipment affects herbicide efficacy. With the AGCO Application Crop Tour locations this year, we’re demonstrating several best practices to maximize the effectiveness of a farmer’s weed control program.”
The Application Crop Tour has been focusing on LibertyLink GM crops because they require a contact herbicide.
“Contact herbicides require more coverage to get an effective kill, as compared to a herbicide such as glyphosate, which is systemic and can be translocated within the targeted weeds,” explained Jason Lee, AGCO agronomist and farm solutions specialist. “So, a herbicide like Liberty is going to be a little more sensitive to errors in sprayer setup that result in less coverage. We want to help educate growers and applicators about optimizing their equipment for the chemistries that they’re spraying.”
AGCO’s sprayer demonstrations this year were done in the United States, so much of the focus was on corn and soybean crops, but the concepts apply broadly. One of the demonstrations focused on improper system clean-outs, which can also lead to significant crop injury when changing fields.
“When the spray boom hasn’t been cleaned out properly, the new chemical enters the boom at the centre and pushes the first chemical out of the boom from the centre toward the tips, creating a recognizable V-shaped pattern of crop damage,” Lee said.
AGCO claims the agronomic results obtained from the demonstration sites emphasize the value offered by sprayers that have self-priming, recirculating booms and product-recovery systems, which minimize contamination issues that lead to crop injury while also preventing product settling within the tank and clogged nozzles.
And, of course, getting the right product applied consistently across the field at the right rate is a major tool in preventing weed resistance. So, making sure a boom is fully primed on entering the field may be one of the most important features offered on the brand’s sprayers.
Goebel added, “If you start spraying before the boom is fully primed, you risk poor herbicide coverage and create an opportunity for weed escapes that could lead to future herbicide resistance. The self-priming boom boosts productivity by saving time and eliminating wasteful spraying on the field edge.”
More results from AGCO’s crop tour will be made available soon, including the effects of boom height, droplet size and application speed.