Many growers who plant PhytoGen brand cottonseed containing the WideStrike Insect Protection trait will not have to set aside a portion of their acres for a non-Bt refuge in 2008, Dow AgroSciences announced.
Dow said EPA has accepted the natural refuge option for growers in the area largely from Texas to the East Coast. The decision was based on studies showing that other crops and non-crop plants can serve as hosts for susceptible tobacco budworms, bollworms and other caterpillar insects in cotton.
Farmers in selected counties in Texas and in Florida south of Highway 60 must continue to provide a non-Bt cotton refuge as part of an insect resistance management program for cotton containing WideStrike.
“We're committed to maintaining PhytoGen brand cottonseed as an industry leader,” says Joe Sobek, global business leader for cotton at Dow AgroSciences. “This natural refuge option allows growers to plant more high-yielding PhytoGen brand cottonseed while maintaining a strong defense against troublesome cotton pests.”
WideStrike, which contains a trait that expresses the Cry1F and Cry1Ac proteins from Bacillus thuringiensis in cotton plants, provides season-long protection against leaf-, square- and boll-feeding worms.
The natural refuge for PhytoGen brand cottonseed containing WideStrike comes after extensive scientific research showed that a sufficient number of cotton bollworms and tobacco budworms — key pests controlled by WideStrike — were present on non-cotton crops and other plants, Sobek said.
“The presence of these pests outside of cotton, partnered with the dual-gene insect control efficacy of WideStrike, greatly reduces the chance that these pests will develop resistance to the technology.”
Until now, farmers have been required to plant a 5 percent “unsprayed” or 20 percent “sprayed” refuge of non-Bt cotton for each 100 acres of WideStrike or Bollgard or Bollgard II cotton they planted.
The natural refuge option will be available for PhytoGen brand cottonseed containing WideStrike planted in Alabama, Arkansas, Florida, Georgia, Kansas, Kentucky, Louisiana, Maryland, Missouri, Mississippi, North Carolina, Oklahoma, South Carolina, Tennessee, parts of Texas and Virginia, beginning with the 2008 season.
The Texas counties of Brewster, Crane, Crockett, Culberson, El Paso, Hudspeth, Jeff Davis, Loving, Pecos, Presidio, Reeves, Terrell, Val Verde, Ward and Winkler are excluded from the natural refuge option.
EPA previously established prohibitions on the planting of Bt cotton in the Texas Panhandle counties of Carson, Dallam, Hansford, Hartley, Hutchinson, Lipscomb, Moore, Ochiltree, Roberts and Sherman as well as south of Highway 60 in Florida. These restrictions still apply with the approval of a natural refuge for cottonseed containing WideStrike Insect Protection.
“Dow AgroSciences is excited to be able to offer many cotton growers a more convenient and economical approach to effectively manage important cotton pests by enabling them to plant PhytoGen brand cottonseed containing WideStrike without Bt cotton refuge requirements,” says Sobek.
EPA said the current, structured refuge constraints will continue for pink bollworm resistance management in 15 counties in the trans-Pecos area of Texas, Arizona, New Mexico and California.