By next year, no less than four new cotton biotechnology traits are expected on the market. This season alone, Bayer CropScience/FiberMax Seeds and Monsanto are rolling out new transgenic technology.
At the recent Southeast Cotton Conference, representatives from Monsanto, Dow AgroScienes, Bayer CropScience/FiberMax Cotton Seed, and Syngenta discussed the second wave of biotechnology and what it will offer farmers in the field.
According to Walt Mullins, Monsanto cotton technical manager, Bollgard II offers "increased efficacy, expanded spectrum, a better resistance management tool, a better IPM tool, better yield potential and hopefully simpler, easier insect control for growers."
Monsanto received registration for Bollgard II before Christmas 2002. In the initial launch this year, Monsanto is anticipating less than 100,000 acres of the Cry1Ac/Cry2Ab Baccillus thuringienisis (Bt) toxin in varieties from Delta and Pine Land, Stoneville and FiberMax.
The two genes together in the Bollgard II package deliver an effective punch against lepidopteran pests. The second toxin expresses itself in high levels in the leaves, squares, bolls and flowers, Mullins says. "Bollgard II gives a significant reduction of worms relative to Bollgard. There are added benefits of the two genes working in concert together."
Bollgard II has excellent activity on beet armyworm, fall armyworm, soybean loopers, tobacco budworm, and pink bollworm. Producers may have to treat for cutworms.
"Will we ever have to spray for lepidopteran control with Bollgard II?" Mullins asks. "Based on our field experience, we don’t think it’s very likely you’ll have to spray. However, we are working with a biological control mechanism and trying to control a biological pest in an ever-changing environment." He advises growers to continue to scout Bollgard II for leps and make any necessary supplemental insecticide applications if pests exceed threshold until "growers get more commercial experience with this new technology."
Researchers found a significant decrease in boll damage with Bollgard II relative to Bollgard. In the presence of significant insect populations, Bollgard II also showed a yield increase when either sprayed or un-sprayed, and had significant higher first position fruit retention compared to Bollgard.
The second toxin makes Bollgard II a "more robust product" than Bollgard, thus offering a better resistance management program. The two toxins appear to work differently on the insects. These different "modes" of activity make rapid development of resistance much less likely.
For the 2003 season, the refuge remains the same as for Bollgard, at 5 percent unsprayed or embedded or 20 percent sprayed. However, some entomologists would like to see the Environmental Protection Agency (EPA) reduce the refuge requirement for Bollgard II.
Mullins says growers can buy Bollgard II in limited quantities in 2003, generally in 10 to 25 bag amounts. The price for Bollgard II will be about $6 to $8 per acre more than Bollgard. For growers in the Carolinas and Virginia and other discount areas, the cost will be $4 to $6 more per acre relative to the Bollgard price. "With limited quantities available, Monsanto and the seed companies are hoping that growers will want to evaluate the insect protection advantage of Bollgard II for their farming operations in 2003."
Liberty Link will offer growers a new weed control system in cotton, says Lee Rivenbark, FiberMax Cotton Seed sales manager. The new system will allow growers to spray Liberty herbicide over-the-top to control broadleaf weeds and grasses. It will be launched in FiberMax cotton varieties.
Bayer CropScience/ FiberMax Cotton Seed was anticipating registration for its Liberty Link Cotton in the first quarter of 2003. "We have a very aggressive production plan to meet demand in 2004," Rivenbark says. Seed availability will be very limited this season. "Our objective is to evaluate herbicide performance on the farm and collect agronomic data. Everything we learn this year is just in preparation for the 2004 launch with an excellent seed supply."
Liberty Link gives growers a new postemergence system, Rivenbark says. The active ingredient in Liberty herbicide is glufonsinate-ammonium, which leads to a rapid disruption of photosynthesis. "Managing weed resistance is a key component for growers today. The different chemistry will allow growers to manage weed resistance."
Liberty Link offers growers a wider application window and can be applied up to 70 days before harvest. "That window of application will be much wider than what’s currently out there," Rivenbark says. It also provides excellent control of morningglory species and hemp sesbania, pigweed, johnsongrass, barnyardgrass and others. "It’s an excellent tool on cotton."
Bayer CropScience will launch Liberty Link in its highly touted FiberMax cotton genetics, which are noted for their yield potential and quality characteristics, Rivenbark says. "Bayer CropScience is committed to bringing new technologies to bring value to growers and help them compete more effectively in the global cotton economy.
Syngenta anticipates a 2004 registration for Vip Cotton, the developmental name for its entry into the transgenic cotton market. Vip is short for vegetative insecticidal protein. The Vip trait is an exotoxin, and has a novel mode of action compared to Cry1A, says Frank Shotkoski, Syngenta Biotechnology global cotton traits technical manager.
Vip Cotton expresses a protein that insect pest larvae cannot tolerate. The larvae stop feeding and soon die. It offers full season control of most lepidopteran pests, including the Spodoptera species, such as fall armyworms and beet armyworms.
Shotkoski said the Vip protein also offers a potential choice to minimize the threat of insect resistance. "It’s a totally new choice for insect resistance management," Shotkoski says. University researchers tested Vip cotton in Mississippi, Texas, Louisiana, Georgia, Arkansas and North Carolina during 2002. Syngenta plans more trials in anticipation of a 2004 launch.
"The Vip protein is expressed in the entire cotton plant," Shotkoski says. "There’s very good expression in the floral area of the plant."
Under very heavy pest pressure in 2002, Vip cotton had very little boll damage and demonstrated effective bollworm control throughout the season in North Carolina, Shotkoski says.
"We’re very excited about this product," Shotkoski says. "This is a new family of Bt toxin that will offer benefits for other crops as well."
In cotton, Syngenta has a product development agreement with Delta and Pine Land Company to evaluate Vip and place the trait into the seed company’s elite germplasm.
In the short-term, Syngenta plans to stack the Vip trait with an existing herbicide tolerance trait in cotton. Down the road, the company plans to stack it with a proprietary glyphosate tolerance trait.
Dow AgroScience unveiled the name of its entrance into the biotech cotton marketplace at the Beltwide Cotton Conferences in Nashville, Tenn., in early January. The name WideStrike represents the trait’s key attributes — broad-spectrum and season-long protection.
At the Southeast Farm Press-sponsored Southeast Cotton Conference, Bobby Haygood of Dow AgroSciences told growers that WideStrike is on track for Environmental Protection Agency approval and commercial introduction in 2004 in the company’s elite PhytoGen varieties. The company expects a limited introduction in 2004.
Several seed companies have research agreements with Dow and are incorporating the trait into their elite varieties. It’s expected to be available in multiple seed company varieties in 2005.
The insect protection trait in WideStrike is a combination of the Cry1F/CryAc Bt gene. In 2002, Dow did extensive agronomic, efficacy and Insect Resistance Management (IRM) trials with the trait at 75 locations across the U.S.
WideStrike has a broad spectrum of activity on lepidopteran pests such as cotton bollworm, tobacco budworm, pink bollworm, beet armyworm, fall armyworm, yellowstriped armyworm and cabbage and soybean loopers.
For example, in one test in North Carolina, WideStrike provided more than 95 percent control of bollworms under heavy pressure.
Dow AgroSciences is seeking approval for an IRM program similar to what currently exists to help maintain consistency and extend the durability of all Bt cotton.
The company will use the brand name during 2003 EUP field trials, Haygood says.