Bayer CropScience announced the release of two new Stoneville cotton varieties on Wednesday at the Beltwide Cotton Conferences, touting the company’s dual herbicide tolerant traits in both varieties. With weed resistance spreading across the Cotton Belt, Bayer representatives say the company offers the most diverse, effective tools to combat the weed epidemic.
ST 4946GLB2 and ST 6448GLB2 are the first Stoneville varieties to offer multiple herbicide tolerance with GlyTol and LibertyLink traits for full crop safety to glyphosate and Liberty herbicides when used as directed, according to Bayer CropScience representatives. These varieties also have a two-gene Bt trait to protect against yield-robbing lepidopteran pests.
“These new Stoneville varieties give cotton growers the flexibility to spray Liberty and glyphosate herbicides and develop the best herbicide program for their fields and operation,” said Jeff Brehmer, U.S. product manager for FiberMax and Stoneville. “Growers can use full label rates of Liberty or glyphosate herbicides on tough-to-control weeds without damage to the crop.”
ST 4946GLB2 is an early-medium maturing GlyTol LibertyLink Bollgard II variety with exceptional yield potential, according to the company. It provides herbicide flexibility and crop safety to full labeled rates of Liberty and glyphosate. The variety also offers excellent root-knot nematode tolerance, according to Stoneville representatives, who also note that ST 4946GLB2 is easy to manage with moderately aggressive growth habits.
Bayer CropScience U.S. Agronomic Services Manager Steve Nichols touts the variety’s good seedling vigor and high yield potential.
“It’s also widely adapted across the entire cotton growing region in the U.S., so we’re really excited about that,” said Nichols. “That speaks a lot to the stability of this variety and the consistency of the performance of it.”
A second variety, ST 6448GLB2, also made its debut in San Antonio. Nichols said ST 6448GLB2 is a full season maturity, GlyTol LibertyLink Bollgard II variety that provides crop safety to full labeled rates of Liberty and glyphosate. Bayer officials say the variety is best suited for the South Delta and Southeast growing regions. In pre-commercial trials, the variety displayed excellent seedling vigor, which results in consistent stand establishment, according to Bayer representatives. Nichols touts the variety’s outstanding yield potential as well as very good fiber quality, and says it is well suited for both irrigated and dryland production.
“Both ST 4946GLB2 and ST 6448GLB2 are ideal varieties for those operations with glyphosate resistant weed issues, but these varieties are not only for the glyphosate-resistant acre,” Brehmer noted. “These new varieties have excellent yield potential and a strong fiber package. Our objective is to bring to market varieties that exceed the yield potential of our current varieties, so these new varieties have the most advanced trait technologies in the best germplasm that Stoneville has to offer.”
ST 4946GLB2 and ST 6448GLB2 have been tested extensively in large and small plots across the Cotton Belt through the Bayer CropScience Cotton Agronomic Performance (CAP) trials. These trials, which are managed by growers using their local management practices, provide real-world yield and quality information and help identify the best new varieties for the cottonseed market.