The road from lab to registration can be a long, and tortured one, for any product. For Aproach fungicide from DuPont, the end of the journey has arrived with news that the U.S. Environmental Protection Agency has granted the product a label. "We were registered on November 30," says Todd Robran, DuPont fungicide portfolio manager. "And we're getting state registrations now."
The product, which is in the strobilurin class of fungicides, but offers added features including enhanced movement in the plant and some curative activity, will be labeled for corn, soybeans and cereals. Robran walked through the key crop areas and the benefits the new fungicide provides in an interview with Farm Progress.
"As we look at Aproach, the thing that has been exciting is control of white mold," he notes. "Back in 2009, which was a big year for soybean white mold, we saw activity from Aproach." Since then, DuPont has worked with universities to test the product and it has performed well. Yet Robran says this is part of a control strategy, not a silver bullet that allows you to throw away other approaches.
"We don't want to throw out all we have learned," he says. "Farmers should stick with proven strategies including variety selection, row spacing and other agronomic practices that help control white mold."
Yet if the problem does spring up, Aproach can be help keep it under control.
The recommendation for soybeans raised under extreme white mold pressure - perhaps following dry beans, which can harbor the disease - is to use a two-pass program with 9 ounces of Aproach at R1 and a second 9-oz. application 10 to 14 days later.
Outside of those high pressure areas, DuPont recommends a single application of 9-oz. at R2 - which can prevent establishment of the disease. Aproach also has activity on other key soybean diseases including septoria brown spot and frogeye leaf spot.
For corn, gray leaf spot is the top target along with rust. The key timing would be VT to R1 and that's the lead recommendation. But DuPont is ready to play in the sequential application business noting that if you're in a high-yield situation with a "race horse" hybrid the two-pass approach is a sound strategy. The first pass would be at about V5 with the second at the VT or R1 timing.
For cereals there are two key application times. "Aproach will offer the most benefit if it goes on at tillering time, which would allow a grower to add [the product] to a herbicide as a tankmix. That would stop early season diseases," Robran says.
There is a later timing - at flag leaf - to control disease. Like other strobilurins Aproach is not recommended for application at heading. It does not control head scab anyway.
Tactics and advancements
Aproach is another in the strobilurin class, but no two chemical compounds are exactly alike. The Dupont strobilurin - picoxystrobin - offers translaminar movement, which means it can get deeper into the plant canopy at application.
In addition, this active ingredient is showing curative activity as well, but Robran is quick to define that term: "As I talk curative it's about when you make the decision to treat. There can be delays between when you decide to treat and when the product goes on."
He explains that in that "decision window" a disease can get rolling but not be visible. The curative ability of Aproach would give you a little breathing time between decision and application. But curative does not mean a reversal of disease - you can't turn brown tissue green. Timing is still the key with fungicides for best results.
Since strobilurins have been on the market there have been signs of resistance. Robran notes that the company has a resistance management plan, which will include a premix product by the end of 2013. In addition, the company is also bringing other modes of action to market. "About 25 to 30% of Midwest acres are treated with a fungicide, so there's still a vast number of untreated acres and we feel that strobilurins will be effective going forward."
Talk to your local agronomist or consultant about the new product and how it fits into your crop disease control program.