Corn+Soybean Digest

Herbicide-Tolerant Crops: A Moving-Target Update

Transgenic crop technology left the "wow" stage in 1997. And in 1998 it entered the all-out competitive war stage among the chemical-company giants that brought us the technology.

Little wonder. Hundreds of millions of dollars per year - and billions longer term - are at stake.

Monsanto's Roundup Ready soybean system created perhaps the biggest product introduction excitement in chemical and seed industry history - certainly in recent history. Some scientists called it "Roundup Ready mania."

It sent chills down the collective spines of competitors - and launched a marketing war on a scale likely never seen before.

It's too early to assess what will happen if the announced merger of the two biggest rival companies, Monsanto and American Cyanamid, becomes final.

So far, the big winners are farmers.

Two of the major players, DuPont and AgrEvo, cut prices on their competitive herbicides. DuPont's price cuts varied by herbicide, but, on balance, they were deep.

AgrEvo, with its Liberty Link system for corn and also for soybeans in '99, lowered the price of Liberty herbicide some, too. The company also added 44 more weeds "controlled" to its label, bringing the total to 101 grass and broadleaf weeds.

Seed companies that put those herbicide-resistant genes into the crops involved - and that's almost all of them - are locked in a competitive battle as well.

More than 100 seed companies, for example, now offer Roundup Ready soybeans, and a similar number offer the Liberty Link corn technology. This year, Roundup Ready corn was introduced by one company, Dekalb. And Liberty Link soybeans were supposed to hit the market, but the launch was postponed because the expected clearances didn't come from the European Union.

Last year was the second year farmers had Roundup Ready soybeans, except those who participated in Experimental Use Permit testing. Most growers were very happy with the weed control results. Many, if not the majority, were happy with yield results.

But "disappointing" was the word many growers used to describe some varieties they tried. Some university agronomists maintain that yield potential has a ways to go on many varieties.

Probably no scientists and only a small percentage of growers smarting from subpar yield results blame the technology per se. The blame is on some seed companies that rushed the breeding process to cash in on the new technology, which farmers eagerly awaited.

Scientists, and even most growers who sacrificed some yield, feel that the yield problem will be overcome within two or three years.

Meanwhile, STS soybeans have continued to turn in grade-A performances, with good weed control, no crop injury and excellent yields. They were still gaining acres before STS herbicide prices were cut, and those price cuts were expected to hike acreage in '98.

Poast Protected corn continues to gain converts and acreage. One big reason is that it gives farmers a good tool to hammer stubborn weeds that have come on strong in recent years. That's because those weeds aren't controlled by some otherwise excellent, widely used herbicides.

IMI-resistant corn, the first herbicide-resistant crop out the chute, faltered a bit after its introduction but then grew at a moderate pace. The introduction of Lightning herbicide by American Cyanamid gave IMI corn a new demand boost.

Last year, Garst Seeds also came out with a gene-stacked corn hybrid resistant to both IMI and Liberty herbicides. Garst also has a hybrid that combines genetic resistance to Lightning and Liberty herbicides, as well as Bt protection against European corn borer.

Overall, most experts predict the transgenic or biotech crop revolution will continue to build momentum. And although it toughens the challenge for plant breeders, stacking genes to include several beneficial traits in one variety or hybrid is the wave of the future, say most scientists.

One cloud has hung over the revolution. That's the acceptance of transgenic crops in Europe. The 15 countries that make up the European Union have proved to be a formidable challenge. But the light at the end of the tunnel has brightened a little with recent positive developments.

For details on all of these herbicide-tolerant crop developments, read the individual stories in this Special Report.

Corn+Soybean Digest

STS Soybeans: Still Gaining Acres

When Roundup Ready soybeans were introduced, some observers thought STS beans would soon be phased out.

That hasn't happened, and Norm Husa doubts that it will anytime soon.

"The yield of Roundup Ready soybeans does not equal that of STS beans in our comparisons," says Husa.

As owner and operator of Husa Seed Farms, Barneston, NE, he produces certified seed of Roundup Ready, STS and conventional varieties.

STS soybeans are at this time "about as good-yielding as you'll ever find in our experience," he says.

Introduced in 1994, STS (sulfonylurea-tolerant) soybeans are considered the grandfather of herbicide-tolerant soybeans. Acreage has increased every year, reaching 5 million in 1997, then jumping to between 6 million and 8 million this year.

"The STS system captured more attention this year because of a 75% price cut of its partnering herbicides," explains Aaron Hager, University of Illinois weed scientist.

"From that respect, I think we'll see an increase in the number of acres planted," says Hager. "The future of it is hard to tell. I think the reduced cost of the herbicides associated with it will keep a lot of people interested."

More than 100 companies now offer STS soybean seed, and some are increasing supplies and offering new varieties.

Growers use DuPont's Reliance STS or Synchrony STS herbicide on STS beans.

"Both products control a very wide range of broadleaf weeds and tankmixing with a grass product completes the programs," says Fran Castle, at DuPont.

For '98, DuPont offered an Authority First-Synchrony copack for waterhemp and nightshade control.

Husa's problem weeds are velvetleaf, cocklebur and sunflower. He says he gets good control with one application of Synchrony. For grass control, Husa uses Fusion. This year, the tankmix cost him about $14/acre.

"With the technology fee we have to pay, the Roundup Ready system gets kind of expensive," Husa states. "There's a place for it, but not all places."

Weed control has been better than in his Roundup Ready soybeans, too.

"Sometimes you have to use Roundup twice because it doesn't offer residual control," he says.

According to Hager, Roundup isn't the best option for some weeds. For example, Reliance and Synchrony do a better job on smartweed and velvetleaf than does Roundup.

Some growers don't want the restrictions associated with the Roundup Ready system, he points out. Those restrictions don't exist with an STS system.

"I don't think STS soybeans are going to have as much of the market as Roundup Ready beans, but it's still a viable system for a lot of producers," says Hager.

Castle explains that the appeal of the STS system, from the beginning, has been the crop safety and proven yields that growers can achieve.

With STS beans and their accompanying herbicides, there's no crop injury, the beans canopy early and often yield better than conventional beans, according to Castle.

"I think the results speak for themselves," she says.

Corn+Soybean Digest

Don't Miss Our Special Report Doubleheader

Attention soybean growers in 10 North Central states. You will find polybagged with this issue one of the most important reports you could possibly read this year.

The topic: soybean cyst nematodes, SCN for short. Aside from weeds, they're the most costly soybean pest of all - costing a billion dollars-plus per year.

The Special Report, "Let's Declare War On Cyst Nematodes," could change your profit picture considerably starting this fall. Read, no, study it thoroughly, then take action.

For readers in the other 20 states where SCN is found, we urge you to test to see if you have them. And if you do, take action now. Those tiny buggers can steal you blind.

Note: Catch the discussion on SCN on AgDay television, Aug. 14, as part of a half-hour program on soybeans.

Our second Special Report, "Herbicide-Tolerant Crops," is bound into this issue and goes to the entire circulation. Sponsored by Asgrow Seed Co., it's our fourth-annual update on this cutting-edge technology.

We invite you to pull it out of the magazine, read it thoroughly - and profit from the exercise.

Corn+Soybean Digest

SCN Fooled These Growers

"We got knocked over the head with it last year."

Gary Klaassen is referring to the SCN problem that clobbered his 60-70 clients in 1997.

"We could find the symptoms about everywhere," says Klaassen, a Pioneer sales rep in northwestern Iowa.

He knew there was SCN in his territory, but thought it was limited to a small area. Spotty plant yellowing in other areas was blamed on iron chlorosis, and growers planted chlorosis-tolerant varieties to combat it.

But the spots kept getting bigger, and last year the problem worsened when late-summer weather turned dry.

"The drouth enhanced our cyst nematode problem," he says.

After attending a scouting school at Iowa State University, Klaassen dug up plants and examined the roots with a magnifying glass.

"We found out what the real problem was," he states.

Clients who planted SCN-resistant soybean varieties last year got about 10 bu/acre higher yields than those who didn't.

Corn+Soybean Digest

Nitragin-Brand Inoculants Celebrate 100th Anniversary

In today's corporate world, staying in business for a century is no small accomplishment.

And Nitrogen-brand inoculants, the world's first agricultural inoculants, celebrated their 100th anniversary in June.

"It is quite an accomplishment for any company to reach its hundredth anniversary," declared Tom Winkofske, president of LiphaTech, the manufacturer of Nitragin inoculants.

"Not only have we reached that milestone, but after 100 years, the Nitragin-brand line has never been in a better position. And our future continues to look even brighter."

The success keys have been a strong research program and development force, backed up by a positive-thinking work force, Winkofske noted.

That commitment to research and development was reaffirmed last year with the introduction of Cell-Tech 2000, according to Winkofske. It's a liquid soybean inoculant that can be applied either on-seed or in-furrow.

Corn+Soybean Digest

SCN Signals Can Trick You

Most growers seem to want to find anything but soybean cyst nematode in problem fields.

Maybe that's why it's usually the last thing they look for.

"Farmers will look at pesticides, fertility, soil compaction," says Walker Kirby, University of Illinois plant pathologist. "Soil sampling (for SCN) is usually one of the last things they do."

Maybe that's because SCN is a sneaky little devil, sometimes posing as compaction, herbicide carryover, a nutrient deficiency or any fungal disease imaginable.

"What growers are first seeing is a yellowing of the plants," says John Ferris, a Purdue University nematologist.

That can mean that SCN has a firm hold on those plants - or that the crop has a nutrient deficiency.

SCN is commonly confused with iron chlorosis. But iron chlorosis symptoms usually appear in June; SCN yellowing occurs in July or August.

Some growers hope to cure the yellowing with a shot of manganese, Ferris says. If the crop isn't manganese deficient, however, the beans may look better, but not yield better.

Dry, sandy fields in southern Illinois are often accused of having potash deficiencies rather than SCN. Symptoms of both include a burning or dying of leaf margins, Kirby says.

SCN can be confused with most any fungal-type root disease, Ferris adds.

Some growers may have pockets of phytophthora root rot, rhizoctonia or fusarium root rot, especially if they have heavy soil that stayed wet and cool all spring, warns Pat Donald.

Donald, a University of Missouri extension nematologist, recommends that growers be "good scouts and problem solvers and look at a wide range of things. The best thing a producer can do is dig up a plant and the soil around it and take it to a diagnostic lab to see if there are any diseases."

"Or if they have a thin stand, they can take seed in for a germination test. If they think they have herbicide carryover, they need to go back and look at their records and see what they put on the fields.

"And they can always do a soil test and see if soybean cyst nematodes are present."

Actually, Donald recommends soil testing every soybean field for SCN, whether it appears to have a problem or not.

Corn+Soybean Digest

Poast Protected Corn Ends Grass Troubles

One of the oldest herbicide-resistant technologies still may be the least-expensive solution to tough grass problems in corn.

Sethoxydim-resistant (SR) corn, also known as Poast Protected corn, is resistant to the active ingredient in BASF's Poast and Poast Plus herbicides. One of the first postemergence grass herbicides for soybeans, Poast is deadly on a long list of grasses and even handles tough ones like woolly cupgrass, shattercane, wild proso millet, jointgrass, johnsongrass, wirestem muhly and quackgrass.

If these or other grasses cause your worst weed-control headaches, SR corn may well be part of your solution, say weed scientists.

When hybrids resistant to Liberty and now Roundup herbicides became available, there was some question about whether SR hybrids would silently fade away.

At least six seed companies sold a dozen or so SR hybrids for 1998. Most are in the 102- to 110-day relative-maturity range, but Dekalb has a 99-day SR hybrid and one rated at 118 days.

While some companies have dropped their SR corn, the same companies that sold seed for 1998 are expected to have seed available in 1999. New hybrids from elite genetic parents are currently in research. So, while the selection may be small, SR hybrids should yield with better conventional hybrids.

"It shouldn't be too difficult for Midwest corn growers to obtain a variety that would work in a grass-infested cornfield," says Harry Leffler, Dekalb agronomist.

Dale Sorensen, Dekalb's director of agronomic strategy, says his company is not giving up on SR corn.

"When you look at each of the herbicide technologies, there is a specific situation where each herbicide resistance may have a fit," he says. "The fit for SR corn is where grasses are the major weed problem."

Sorensen says Poast is especially strong on grasses that reproduce from rhizomes because it translocates rapidly from the leaves to the roots.

Dekalb introduced two new SR hybrids for the Southeast this past spring. Both were welcomed by growers in the Carolinas, Georgia, Alabama and northern Florida, where Texas panicum has become nearly impossible to control.

Bob Youmans, Furman, SC, had been battling Texas panicum, johnsongrass and a bit of common bermudagrass for several years.

"One application of Poast on Poast Protected corn was enough to control the panicum," Youmans tells. "It takes a couple of applications on the perennials because of the rhizomes, but it's still less expensive than other chemicals."

He planted in April and early season weed control looked good. He isn't looking forward to harvesttime, though.

"To make any of the herbicide- resistant corn systems work, you must have crop canopy to hold back later-season weed growth," Youmans states. "The weather here was so bad that even corn that was near canopy by mid- June was burned back by heat and drought. Any rain we get from now on is likely to grow weeds, too."

George and Nancy Krom grow corn and soybeans in heavy muck (high organic matter) soils near Rochester, IN. They've been growing Poast Protected corn on those soils for four years.

"Most soil-applied herbicides get tied up in the soil organic matter, so it's difficult to get prolonged control," George explains. "The wide application window for Poast in SR corn lets us wait until shortly before the corn canopies to apply the herbicide."

The Kroms, who also have tried other herbicide-resistant corns, find that the SR corn system is the least expensive.

This year, they used 1.5 pints/acre of Poast Plus at a cost of about $10.50 an acre. They applied it with crop oil and ammonium sulfate, which added another $1.50 to their per-acre cost.

Finally, to get some residual control, especially of broadleaf weeds, they added a pint of atrazine, which cost about $1.64 per acre. Total for the SR corn program, then, was $13.64/acre.

That compares to $14/acre for weed control in their Roundup Ready corn. They paid $12.50 an acre for a quart of Roundup plus $1.50 for crop oil and ammonium sulfate.

"We could use atrazine with the Roundup, too, without the costs getting out of line," says George Krom.

Both programs contrast with the roughly $25 an acre they spent for Liberty on Liberty Link corn in 1997. Even with the lower price for Liberty this year, cost of herbicide and ammonium sulfate was projected at roughly $20/acre.

The Kroms and Youmans list crop safety as another reason they like Poast Protected corn.

"Poast has no effect on the SR corn, unlike other popular grass herbicides," says Krom. "And if we used a product like Accent, we couldn't wait as long to apply it as we do with Poast."

Corn+Soybean Digest

Liberty Link Soybeans Coming Next Year

After a bit of a false start this past spring, at least two Liberty Link soybean varieties will be available for 1999 planting.

Rick Mohan, soybean product manager for AgrEvo, says Croplan Genetics and Mark II both will have limited supplies of two late Group II varieties. There may also be a Group V variety for the Midsouth and Southeast.

Bob Hartzler, Iowa State University extension weed specialist, has observed Liberty Link soybeans in research plots for the past two years.

"Liberty Link may take a little better management than our historical weed control programs, in that some weeds are on the borderline of what Liberty can control, even at the 28-oz rate," he says.

Specifically, the problem weeds seem to be yellow foxtail and lambsquarter. Most others are controlled with 24, 20 and sometimes 16 oz, depending on the size of the weeds.

The label for Liberty, when used with Liberty Link soybeans, allows for two applications of up to 28 oz, or no more than 56 oz total for the growing season.

Hartzler says Iowa State weed researchers looked primarily at a straight Liberty program, rather than Liberty in combination with other herbicides.

"In our plots, control was very comparable to what we saw with Roundup Ready beans," he says, adding "we don't have a lot of yellow foxtail or lambsquarter in these plots.

"Liberty Link is a viable option, but I'd compare costs based on a couple of applications of something less than the full 28-oz rate," Hartzler advises. "For 1999, growers also need to consider whether the varieties available will be among the best-yielding for their area, since, in the end, yield is still more important than the herbicide program, providing costs end up being similar."

Corn+Soybean Digest

Stop Nomadic Nematodes

They'll hitch a ride on anything that moves, be it dust, Canada geese or water.

But the main way soybean cyst nematodes spread? Maybe the answer's in your mirror.

"The biggest way is through impatient farmers who are out working fields that are too wet," says Pat Donald, a University of Missouri extension nematologist.

"They get mud on everything and just carry dirt from field to field."

To keep SCN from spreading, work fields not known to have nematodes first, then move your rig into infested fields.

Or power-wash equipment between fields. Just don't move soil back and forth between fields, she reiterates.

"I never knew I had a problem, so I didn't clean my equipment off," admits Dave Broghamer, Decorah, IA. He's in his first year of fighting SCN on 60 acres.

"I just assumed this year that I had already spread it to all the other fields, so all the soybeans I planted are nematode-resistant," says Broghamer.

"Some think soybean cyst came into this country with soil that was brought in as inoculant," Donald says.

Others surmise that SCN has been around all along and that it was surviving on weeds, says Jamal Faghihi, a Purdue University research nematologist. "When soybean cultivation became widespread, it started showing up in different places," Faghihi adds.

Once it was found in North Carolina, it was discovered throughout the Southeast and later into the Midwest, reports John Ferris, a Purdue University nematologist.

"We first found it in 1970 in southern Indiana. Eight years later we found it in the northern border of the state. Then we found it all over."

However it got here, SCN is here to stay. Canada geese and other waterfowl are active carriers of the costly pest. So is water, says Donald.

"We know that water moves it; I documented in the flood of '93 that it was being brought intodifferent areas along the Missouri River."

Blowing soil also carries SCN, says Walker Kirby, University of Illinois plant pathologist. He, too, suggests scrubbing and spraying tillage tools, tires and fender wells, for example. Custom harvesters should especially be asked to wash equipment because "you have no idea where they are coming from."

"If you take time to do this, it will reduce the spread," Kirby says

Corn+Soybean Digest

Lightning Lights Fire Under IMI Corn Sales

The turf battles over herbicide-resistant crops have raged from the cornfield to the courtroom. But the first of these new-age weapons, IMI (imidazolinone)-resistant corn, continues to enlist more recruits and occupy more real estate.

The IMI-resistant gene was developed by American Cyanamid, initially with resistance to Pursuit herbicide. Garst Seed Co. (then ICI/Garst) and Pioneer put the first IMI-resistant hybrids on the market in 1991. In the next few years, most major seed companies added IMI resistance to their hybrid lineups.

IMI corn got a boost in 1997, when American Cyanamid released Lightning herbicide for one-pass, over-the-top weed control. Lightning blends the active ingredients of Pursuit (imazethapyr) and Arsenal (imazapyr) to control a wide spectrum of grass and broadleaf weeds. This spring, growers planted upwards of 3 million acres of IMI corn.

"Our IMI corn volume is going up every year," says David Weatherspoon, Garst's director of marketing. "IMI is our leading herbicide-resistant trait. The addition of Lightning herbicide has helped the demand for IMI-resistant hybrids."

"Asgrow is introducing IMI resistance into more elite hybrids every year," agrees Mike Wojtalewicz, the company's corn product manager.

"From 1997 to 1998, IMI corn acres nearly doubled," says Barney Bernstein, Lightning product manager for Cyanamid. "We put a lot of educational effort into making sure growers know how to use this system. Three times as much Lightning was used this year as in 1997."

While Lightning was cleared for field use in 1997, many corn growers used it for the first time this season. John Wescoat, New Madrid, MO, planted Pioneer 3395IR on March 28.

"I didn't put down preplant herbicide," says Wescoat. "Wet weather kept me out of the field until the corn was 18" tall. I had a lot of grass and morningglory in the field at that time, and sprayed Lightning over the top. It wiped out the weeds, but it took awhile.

"Because the corn was so tall, I cultivated some of it after I sprayed Lightning," he adds. "In hindsight, I probably shouldn't have. But Lightning did a good job. In fact, I wish I could have gotten it on more corn acres. I wound up having to fly on Accent and atrazine on some big corn to get rid of johnsongrass."

Lightning isn't cheap.

"But it's not as costly as the way I was controlling weeds before, with a preplant herbicide, followed by cultivation then an over-the-top spray," says Wescoat. "That gets expensive."

Corn growers have more weed-control options now - in the same hybrid.

"We are stacking more genetic traits all the time," says Michael Smidt, Garst's marketing communications manager. "We're still expanding IMI hybrids, and also are incorporating other genes, such as Liberty Link. For example, our 8585 hybrid now has IMI resistance, Liberty Link, Bt corn borer resistance and gray leaf spot resistance all stacked together."

That gives farmers more management choices in a single hybrid, but it can complicate score-keeping.

"When we stack genetic traits, it's harder to pinpoint the share of any one characteristic," agrees Smidt. "If a farmer buys a hybrid that incorporates both IMI resistance and Liberty Link, which most influenced his decision to go with that particular hybrid?"