Insecticides 2016: Out with the Old, In with the New Reality
It isn’t so much that U.S. growers will have to decide among the abundant, groundbreaking new insecticides to use in 2016 — it’s that there is a lack thereof, and they will need to potentially spend more to manage resistance issues with the existing ones, while at the same time contend with low commodity prices.
This isn’t to say there is no positive news out there. Far from it. A limited number of new insecticides show promise in filling key product voids, while the El Niño weather effect inspires hope of drought relief in specialty crop-dominated California, and prices of high-value vegetables in the Southwest remain buoyant.
In the row crop-ruled Midwest, the outlook is bleaker.
“I think it’s a very challenging situation. Everyone is concerned about what 2016 looks like,” says Joe Mares, North America Portfolio Manager of Insect Control Products at DuPont Crop Protection.
Dr. Christian Krupke, Professor of Entomology at Purdue University, says he hears from both growers and agronomists that they are taking a harder look at applying fungicide and insecticide sprays together, both prior to planting as seed treatments and in-season as foliar sprays, particularly when pest or pathogen issues can’t be documented.
“If I had to guess, given these commodity prices, you might see a little more decrease in willingness on those elective sprays. If you get a soybean outbreak, people are still going to reach for the insecticides pretty quickly, as they should when they have a population of aphids that exceeds the economic threshold of 250 aphids/plant.”
Mares says the two newest insecticides in DuPont’s portfolio, Exirel and Verimark, protect against sucking and Lepidoteran pests across the specialty vegetable market, spanning tomatoes, peppers, cucurbits, apples, citrus, and more. In places like Texas, they will give growers an additional tool particularly as last year’s weather patterns exacerbated concerns about the risks of growing high-value crops.
For Monsanto, spokesman John Combest says that last year, Roundup Ready PLUS Weed Management Solutions evolved into Roundup Ready PLUS Crop Management Solutions, to reflect the addition of insecticide recommendations and incentives.
“For the 2016 season, Monsanto is adding FMC’s Capture LFR insecticide to the platform. Capture LFR joins FMC’s Hero insecticide and Monsanto’s own Precept as incentivized insecticides,” Combest says. Capture LFR controls seed and seedling pests such as wireworm, cutworm, grubs, armyworm, seed corn maggot, and common stalk borer. Farmers can earn $2/acre when they use the recommended rate along with a Roundup brand agricultural herbicide in corn.
At BASF, its Nealta miticide had a strong first season in 2015, says Christa Ellers-Kirk, Technical Market Manager, “and we expect to see continued growth in 2016 among almond, grape, citrus fruit, and strawberry growers. It offers a unique class of chemistry for strong knockdown power and residual control of spider mites at all life stages.” For corn and wheat growers, BASF’s Fastac insecticide offers broad-spectrum insect control.
Bayer CropScience has high hopes for the latest insecticide to emerge from its labs, Sivanto. Its active ingredient, flupyradifurone, is the first insecticide in the new butenolide chemical class (new IRAC subgroup 4D) and with its honey bee-safe profile it will add to the range of treatment options available to growers.
Originally targeted at the horticulture markets, especially citrus and vegetables, initial adoption in the 2015 launch year was strongest in sorghum and alfalfa; it is highly effective in controlling the newest pest in sorghum, the sugarcane aphid.
According to Frank Rittemann, Bayer CropScience Horticulture Product Manager, Sivanto has also quickly become one of the go-to tools of Florida growers in combating citrus greening disease Huanglongbing, which is vectored by the Asian citrus psyllid (ACP).
Throughout the season growers have access to a number of tools that effectively control ACP; however, they struggle to do so in bloom time because of the limited compounds that are registered for application in this pollinator-sensitive window. “Sivanto is a perfect fit to address growers’ need in that window,” says Rittemann. “Before, growers really didn’t have any effective options.”
Rittemann says Sivanto is set to make a much bigger impact this year following its 2015 U.S. debut, as product availability and awareness expand. The product has also been launched in Mexico, Nicaragua, Guatemala, Honduras, and the Dominican Republic, and has just recently received regulatory approval from the Canadian PRMA.
In 2016, Bayer is also expanding its rollout of Velum Total, a nematicide that also provides early insect control, from Georgia to the Mid-Atlantic states, the Carolinas, and Texas. In addition, it will launch Velum Prime for nematode control in the Pacific Northwest potato and California grape markets.
As Steve Olson, Senior Product Manager with Bayer CropScience points out, insecticide development targeting corn rootworm has lagged because of the introduction of insecticide traits in the crop. “There are a few traditional insecticides that can be effectively used to control corn rootworm … (Growers) just have limited chemical tools right now because of the evolution of insecticide traits that are in that crop today.”
The most significant new product development for addressing Bt resistance Krupke sees on the horizon is RNA interference (RNAi) corn, including Monsanto’s Smart Stax Pro, which is currently in the approvals process. “When you only have two primary tools dominating the market in terms of Bt hybrids – Cry3Bb1 from Monsanto, and Cry 34/35 in Smart Stax corn and in Pioneer’s offering – it’s always good to try to have more options in the pest management toolbox in the event that one of the current approaches start to break down. I think that RNAi technology has the potential to be a big development on that front.”
Monsanto describes RNAi as a natural process cells use to turn down, or suppress the activity of specific genes. This is done through the cell’s natural ability to review RNA instructions inside the cell and then “decide” whether to process the instructions or not. As a result, the process can turn down or stop production of a specific protein, much like a dimmer on a light switch.
Some performance problems with Bt corn hybrids targeting corn rootworms have been reported, most of them in the Western Corn Belt where continuous corn predominates. Of course, there are a multitude of reasons for growing continuous corn out West. But in Krupke’s region — Indiana — he thinks it’s no coincidence that there have been no confirmed reports of Bt resistance.
“We emphasize: stick with the rotation that has been working for you. In a corn-soybean rotation, you’re going to have half as much selection pressure, half as many years in corn as your average Iowa farmer … In addition to the agronomic and economic benefits of rotation, Bt and other pest management approaches in the two crops remain more durable because there is less pressure placed on them.”
The shrinking pool of existing solutions makes it even more critical that integrated resistance management is being followed using different modes of action in a spray program, says Rittemann.
In the Southwest, this spring’s insect pressure could be much lighter than a year ago, owing to the El Niño weather pattern, says Dr. John Palumbo, University of Arizona Extension Specialist and Entomologist based at the Yuma Agricultural Center.
“Nighttime lows have been cooler — in the high-30s for lows, and that’s cold for us,” Palumbo says. “Trying to guess what it’s going to be like is like rolling dice, but I would expect our spring pressure to be lighter than we’ve seen in the last couple of years.”
In contrast to grain prices, the current market for lettuce, broccoli, and cauliflower is “just off the charts,” he says. “This time last year, it was horrible. Prices were very low because we had so much product in the field being harvested; right now product isn’t being harvested as much because of weather.”
He draws attention to the oddities of the fresh fruit and vegetable market. Supplies can be normal one day, but if a big snowstorm hits the East Coast, the inability to physically ship product can trigger a back-up of produce in the coolers and subsequently cause prices to tumble.
One of the biggest ag trends in the desert, he says, is increased demand and production of certified organic produce, despite the challenges posed by insects. At times, he sees organic growers walk away from a crop simply because they can’t control aphids.
“When you stack the best conventional (insecticide) to the best organic products it’s probably less than 50% effective,” Palumbo says. One of the most-used products in organics is spinosad — which up until Dow AgroSciences’ Radiant was registered was the number-one product used in conventional ag, Palumbo says.
“It’s kind of ironic that the same product can be used in both production systems.”
“That’s the silver bullet that the organic industry — at least in the desert — is looking for, is an effective product against aphids in organic crops, and is the focus of what I’m working on right now,” he adds.
Palumbo sees the newest insecticide with a fit in his region in pyrifluquinazon, from Japanese company Nichino America, for control of whiteflies and aphids. It should gain approval in 2016 or 2017, and will be a fit for the Florida, Georgia, and Texas markets as well. The product has excellent activity against whitefly adults and has been very effective in suppressing virus transmission in melon crops, he says.
He says he also hopes for an effective thrips greening product to add to the rotation similar to Radiant, that has a clean, reduced-risk profile. “The agchem industry has been very good to this produce industry; they always come through when we’ve needed new products,” he adds.
Pollinator Pressure in 2016
Pollinator concerns are expected to continue to shake up the U.S. regulatory environment in 2016.
“As far as dealers are concerned, I think this push to limit insecticides is going to make things difficult. My guess is there are going to be more restrictions and more labeling to protect pollinators,” Bruce Potter, Integrated Pest Management Specialist at the University of Minnesota, says. “Right now we’re in a period where we’re kind of on this teeter-totter between science and politics, so it makes things a little more tenuous.”
U.S. Environmental Protection Agency’s cancellation of sulfoxaflor in November “is sort of a first warning shot of maybe what’s to come,” cautions Dr. Dominic Reisig, Extension Specialist at North Carolina State University. The insecticide does not technically fit the neonicotinoid category at all, but is closely related.
Chlorpyrifos is also on the brink: EPA has proposed to revoke all food residue tolerances for the insecticide; the comment period on the proposal runs through the end of January.
The case of sulfoxaflor illustrates the ripple effect of tools being plucked from the grower’s toolbox.
Labelled as Dow AgroSciences’ Transform, it was one of the most widely used chemicals on sugarcane aphid, a newer invasive pest in the U.S. after it jumped hosts from sugarcane to sorghum. Reisig says that with margins on commodities like sorghum as slim as they are, the pulling of sulfoxaflor’s registration was the tipping point for many growers, who decided to hedge their bets and simply not spray, or move on to another crop.
“Removing a chemical like Transform ends our ability to rotate modes of action, which may lead to resistance faster,” Reisig says. “We’re really sad to see that one go. It had a fit in some other crops as well, and it’s pretty widely used on vegetables. That’s going to be a big gaping hole for us,” he says, adding that Bayer’s Sivanto will be the go-to chemical for sugarcane aphid.
Potter says that in Minnesota, there is strong evidence of soybean aphid resistance to synthetic pyrethroids, at least in part of the soybean population. “That gets a little complicated if we’re not allowed to spray Transform. If we lose chlorpyrifos, the other alternate mode of action, we’re basically stuck with pyrethroids, and that’s not good.” There are tank mixes containing neonicotinoids available, but those have their own problems with environmental groups, he points out.
On the positive side, Western corn rootworm populations are down a bit in his state, he says. As always, knowing the pest populations in individual fields is important. Some corn growers are trying to reduce seed costs by planting hybrids without rootworm traits. This can make economic sense or be risky if the field was not scouted and found to be free of large populations of egg-laying rootworm beetles. In other words, either treating or not treating insect populations could have an economic risk if a field has not been scouted well. Scouting is a crop production input that should not be reduced during harder economic times on the farm, Potter says.
“Guys are going to have some tight belts for a year or so, maybe a little longer, but they’re going to be better managers when it’s over, and there’s nothing wrong with that, but it’s too bad they have to go through economic hardship to do that,” says Potter, adding, “It’s the dealers, too. You get that impression talking to them, that they’re trying to think of how to tighten belts, because growers’ pockets don’t open as easy anymore.”