After one year of limited testing of Vip Cotton, Roy Parker says the soon-to-be released genetically engineered cotton could be good for competition in the marketplace.
Parker, an Extension entomologist with Texas A&M University in Corpus Christi, says Vip Cotton appears to do an excellent job controlling the tobacco budworm and the cotton leaf perforator.
A late-season pest, the cotton leaf perforator is not normally a major pest, but Parker says it is seen in Texas every year to some degree. The product, however, did not adequately control the fall armyworm in his field tests.
The 2002 Texas A&M University study included two test plots planted to Vip Cotton and two plots planted to a non-transgenic parental line, with one of each over-sprayed twice with a cotton insecticide. Average scouting counts were tabulated four times during the growing season.
“The insecticide treatment did reduce insect damage in both varieties, but pest counts were lower overall in the genetically modified cotton,” Parker says.
He found an average of 4.1 percent insect damage in the untreated Vip Cotton, and 2.2 percent insect damage in the treated Vip Cotton plot. In comparison, the conventional cotton was hit with 28.2 percent damage in the untreated plot, and 11 percent damage in the plot treated with an insecticide.
Because Parker did not receive the Vip cotton until late in the planting season, he was unable to see it to completion, and the cotton was destroyed without any yield data. He is, however, repeating the study this year. With an April 16 planting date, he expects to collect yield and agronomic data after the plots are harvested.
“There are very few people who know anything about this cotton, and company rules prohibit researchers from including Vip Cotton in our variety trials. If Syngenta is planning to bring it to market anytime soon, more people need to look at it in the field, because there is still major research work to do,” Parker says.
Because the transgenic product is not yet labeled, tight controls appear to be restricting field testing opportunities. For example, field test plots of Vip Cotton must be surrounded by 40-foot borders, and they may not be planted adjacent to, or compared with, Monsanto's Bollgard varieties.
“My early inclination is that there is no difference between the Vip Cotton and Bollgard cotton, but until we can compare the two side-by-side we won't have a definitive answer,” he says.
Syngenta Crop Protection 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 — the trait found in Bollgard cotton varieties, Frank Shotkoski, Syngenta Biotechnology global cotton traits technical manager, said at the 2003 Southeast Cotton Conference in Rocky Mount, N.C.
Vip Cotton expresses a protein that cannot be tolerated by insect pest larvae, according to Shotkoski. The larvae stop feeding and soon die. It offers full-season control of most lepidopteran pests, including the Spodoptera species, particularly fall armyworms and beet armyworms.
Shotkoski says the Vip protein also offers a potential option for minimizing the threat of insect resistance. “It's a totally new choice for insect resistance management,” he says. “The Vip protein is expressed in the entire cotton plant. There's a very good expression in the floral area of the plant.”
Syngenta is planning field trials this year in anticipation of a 2004 launch.
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, says Shotkoski. “We're very excited about this product. This is a new family of Bt toxin that will offer benefits for other crops as well.”