The popularity of glyphosate herbicide, particularly Monsanto’s
Roundup, is creating marketing opportunities for other herbicide makers.
Some of these new products control volunteer Roundup Ready canola,
while others are promoted for preseeding burn-down to avoid creating
glyphosate-resistant weeds because of overuse.
“Roundup is the 2,4-D of the 21st century. It is incredibly effective
for the cost, so everybody uses it,” said Clark Brenzil, a weed
specialist with Saskatchewan Agriculture.
“It has existed to the exclusion of all others. No residue. There are
Read Also
Powdery mildew can be combine fire risk
Dust from powdery mildew can cause fires in combines.
some new products on the market that can be used in place of
glyphosate, but in general they won’t work with all crops … delay
seeding after application … or they cost too much.”
Glyphosate’s mode of action makes it less likely to result in resistant
weeds than other herbicides.
However, glyphosate-resistant weeds have developed in several
countries. While none of them is a serious problem, Syngenta, which
makes the glyphosate herbicide Touchdown, recently recommended that
farmers make no more than two applications of glyphosate-based
herbicides in a given field during any two-year period.
It advised farmers to use integrated weed management, rotating
glyphosate with other non-selective and selective products with
differing modes of action.
Chuck Foresman of Syngenta Crop Protection in Greensboro, North
Carolina, said the “overwhelming success of Roundup Ready technology
has left us with some opportunities for our products.
“It’s a real concern in the minimum-tillage states down here. We are
finding resistance in several states. Farmers have adopted
(glyphosate). It is inexpensive and it works. The RR technology is
really popular and that market is growing worldwide. …It also means
there are opportunities arising from that popularity.”
For example, the company says its product Gramoxone, which contains
paraquat, can be used as a preseed burndown in place of glyphosate.
Hugh Beckie of Agriculture Canada in Saskatoon said long-term
glyphosate use has caused a few problems when combined with Roundup
Ready crops and their subsequent season’s volunteers.
“We don’t like to see farmers using it pre, post and in crop. That can
cause problems down the road. … So far in Canada we don’t see
(glyphosate) resistant weeds and we don’t want them.”
Volunteer herbicide-resistant canola has become a pest for many prairie
farmers.
In the past, farmers used a preseed burnoff with glyphosate as a way to
control canola volunteers and other weeds. But now the likelihood has
to be assumed that some of the volunteers will be herbicide-tolerant
varieties.
A glyphosate burnoff will kill conventional and several HT canola
varieties, but not Roundup Ready canola, so producers are using a tank
mix of glyphosate and 2,4-D.
But some companies think they can produce a burn-down product that
works better in certain circumstances.
Earlier this month, Dow AgroSciences released PrePass, a mix of
glyphosate and florasulam, a group 2 herbicide.
Dow said in a News release
newsthat its research indicated many farmers
were using more than the recommended one-half a litre per acre rate of
glyphosate to deal with hard-to-kill weeds such as dandelion,
shepherd’s purse and winter annuals.
The company says PrePass will control the weeds and canola volunteers
without having “the worry of topping up rates or off-label product use.”
PrePass is designed for use before planting cereals. It can’t be used
before canola, flax, pulse or special crops because of florasulam’s
residual action.
On the other hand, if used with the appropriate crop, it provides
extended control of second flush weeds, the company said.
Brenzil said the herbicide market “still has some opportunities,”
particularly in preseeding burn-off options for pulses, flax and
specialty crops.
“The ones that are compatible cost a lot or require producers to delay
seeding and may be dependent on additional moisture after application
(to neutralize them),” he said.
