, Farm Journal Seeds & Production Editor
Finding the right genetics is the first step in achieving more pods that add up to more bushels. Photos by the author
Seed signs line up like sentries down the rows of Kip Cullers' field plots. The southwest Missouri farmer strolls by in his characteristic half-trot, spewing out variety numbers with nary a glance at the metal cue cards.
He knows the habits of these varieties like he knows his own children. Cullers will tell you that soybean variety selection is one of the most important decisions he makes each year because it is the foundation to developing an effective and successful crop management plan for the entire season.
With two soybean yield titles back- to-back—last year a record-breaking 154 bu. per acre—Cullers does plenty of bean counting. He manages more than 5,000 acres of corn and soybeans near Purdy, Mo., and this past year achieved a 74 bu. average soybean yield across his farm—nearly double his state's average.
"The first step to higher yields is to select the right genetics for your farm,” Cullers says. "It doesn't cost any more to use the right numbers. It costs a lot to use the wrong ones.”
Sounds easy, but a seed company's product portfolio can contain as much as 50% new releases, creating a challenge to find information on which to base decisions. That situation goes into overdrive for 2009 as farmers have a smattering of new traits and technologies added to the mix.
"Historical performance information is critical when choosing varieties,” says Jeremy Ross, University of Arkansas Extension soybean agronomist. "The general recommendation is to select a variety that has proven to be high-yielding across multiple locations for at least two years.
"That's become something of a problem over the past few years as companies bring lots of new material to market and push for early orders.
"The memory of soybean seed shortages is still fresh, too,” Ross adds. "Many of our growers didn't get any of their top five choices for 2008—they had to choose from their top 10. It's important to be prepared to make those choices, rather than just being willing to take what's available.”
More decisions ahead. The 2009 planting season also brings a mind-boggling array of tempting new traits.
You'll find test plots full of Pioneer Hi-Bred's higher yielding "Y” Series soybean line this year. Using proprietary molecular marker breeding techniques, plant scientists have been able to track and select native genes associated with high yields and stack those genes into Pioneer varietal lines.
Don Schafer, soybean product manager for Pioneer, says the company made a limited supply available to growers in 2008, but will launch 32 varieties ranging from Group 0 through Group VII in 2009. "It's the largest introduction in terms of volume in the history of the company—accounting for nine million acres worth of product,” Schafer says.
This fall, Monsanto Company's second generation Roundup Ready 2 Yield trait will be introduced on one to two million acres for the upcoming planting season. The majority will be available in maturity Group II and Group III and in high-performing genetics from Asgrow and leading regional soybean brands.
David Shenaut, a Monsanto agronomist, says four years of field trials show the new trait outyields first generation Roundup Ready technology by 7% to 11%. "Yield is a hard thing to visualize with soybeans,” says Shenaut, who is based in Mahomet, Ill. "It really means a few more beans per plant—or 55 bu. instead of 50 bu.”
Monsanto identified specific DNA regions in soybeans that have a positive impact on yield. Using new insertion and selection techniques, the gene is situated in one of these high-yielding DNA regions.
Soybeans with new yield-enhancing traits are light-years ahead of past varieties, says yield king Kip Cullers, Purdy, Mo. Pioneer Hi-Bred's "Y” Series soybeans pump up yield by having more pods—at times more beans per pod and larger beans per pod, depending on variety.
Also, new herbicide traits are on the way. This fall, Bayer Crop Science plans to commercially launch LibertyLink soybeans with built-in resistance to Ignite herbicide. "I have 15 LibertyLink varieties on trial this year, and it's an easy trait to work with—it doesn't drag down yield and it offers options to growers who need to address the issue of herbicide resistance,” Arkansas' Ross says.
You'll see two new soybean cyst nematode (SCN) lines for 2009 planting from NK Brand Seeds—a company that is expected to bring the first aphid-tolerant line to market for 2009 in Canada (2010 in the U.S.).
Niche markets get a nod, too. Pioneer will roll out limited quantities of a high-oleic soybean variety in 2009, pending regulatory approval, with a full launch expected in 2010. The company also will introduce the first Roundup Ready ultra-low-linolenic variety in the coming year.
"Soybeans are where corn was 10 years ago,” says Steve Knodle, marketing manager for NK Brand Seeds. "Soybean traits are going to become more available and more stacked as the value of the crop gets reflected in the marketplace.
"We're finding some growers are concerned that it might get too complex. But after you get past the buzz, the cutting-edge new stuff will likely be available in limited supply and growers still need to concentrate on what is right for their farm,” Knodle says.
Variety selection is primarily about risk management, says Iowa State University soybean agronomist Palle Pedersen. "It's not unusual for one variety to outyield another by 15 bu. to 20 bu. or more in the same field,” he says. "The maximum yield potential of each variety is genetically determined and is realized only when management and environmental conditions are perfect.”
Perfect doesn't happen very often, so how do you prioritize? Pedersen says yield and yield stability are first on the priority list. A variety that has shown to be high- yielding and stable across multiple locations and years is less risky.
If multiyear information is available from replicated independent yield trials, that is ideal. However, you may have to use seed company information for the newest varieties. "We suggest limiting new varieties to 10% or 15% of your acreage until we know how it will perform,” agronomist Ross says.
Yield champ Cullers does not take any chances. He routinely requests the opportunity to participate in product advancement trials that allow him to test varieties on his farm before they are commercially available.
Next, match high-yielding varieties to the history of diseases within fields.
"Numerous varieties have good resistance or tolerance to SCN, sudden death syndrome, brown stem rot, iron deficiency chlorosis and phytophthora root and stem rot,” explains Iowa State's Pedersen.
"In the Upper Midwest, or on 80% to 85% of all U.S. soybean acreage, the issues are all belowground. Most of those problems can be addressed through variety selection,” he adds.
Maturity classifications describe the time from flowering to harvest maturity. Planting soybeans from different maturity groups can help minimize risk by spreading flowering, seed fill and physiological maturity.
Ross likes to see his southern growers vary maturity date—as long as they don't get too carried away.
"The trend here has been to get away from Group VI and go as early as late Group IV's for those hoping to eliminate some irrigation or bypass late-season insect and disease threats,” he says. "We have to be careful about going too early because we don't get the height needed and sometimes early beans get caught in rice or cotton harvest and sit in the field too long.”
Grain composition—high oil, protein and amino acid content—are important in your selection process, especially if processors are offering niche market premiums.
Taller plants are generally more susceptible to lodging, but height also influences yield. Dealers should be able to offer you lodging ratings to give an indication of standability.
Cullers finds standability one of the biggest challenges as he pushes soybean yields. "The new genetics don't seem to be squatting down. I'm finding them to be light-years ahead, and I'm really excited about what I'm seeing so far,” Cullers says.
Read the Web Extra bonus content.
The right variety can help you minimize weather-related risks. Field conditions, yield potential, lodging, maturity group, herbicide program, grain composition and disease and pest issues are all part of the equation.
- September 2008