Farmers have begun recognizing that even low insect pressure plus low levels of disease in a field reduces soybean yields much more than ever expected.

"Soybeans have a higher genetic yield potential than what we have been seeing at harvest," said Eric Ifft, Bayer CropScience technical sales consultant in central Illinois. "We know that soybeans have at least a genetic yield potential of 154 bushels per acre because that is the world record soybean yield."

Soybean producers have new challenges and options to consider for protecting soybean yields, such as:



  • Soybean aphids appearing yearly rather than every other year in much of the Midwest.
  • Plant diseases becoming more prevalent.
  • Soybean seed costs going up each year, but the yield potential also increasing.
  • More weather extremes causing environmental plant stresses.
  • New chemistry and research resulting in better crop protection.
The practice of applying a fungicide and insecticide at the same time is addressing all five situations in growing soybeans. "The data clearly supports a yield bump that comes with the application of Stratego fungicide and Leverage 2.7 insecticide at the same time," said David Byrum, Bayer CropScience technical sales consultant in central Iowa. "If pest pressure indicates it's time to make an application of Leverage or Stratego, you should consider making an application of both."

Byrum's counterpart, Ifft, notes how the combination of Stratego and Leverage 2.7 reduces stress to the soybean plant. "First is contact insect control, second is systemic insect control, third is systemic disease control, fourth is curative disease control and fifth is what we call 'Stress Shield,' which protects the plant against environmental stresses like drought, heat, saturated soil and other abiotic stresses."

Bayer CropScience has determined that tankmixing the two products together and applying them at the soybean plant's R3 growth stage (beginning of podding), can achieve excellent results year after year. This tankmix and timing was widely introduced to growers in 2009.

Howard White, Westby, Wis., had 185 acres of soybeans aerially treated with Stratego and Leverage 2.7 at the R3 stage in 2009. "The 185 acres averaged 56 bushels per acre, and 45 acres that we didn't spray averaged 43 bushels per acre. There were also two untreated checks in the 185 acres, and those untreated areas yielded 10 bushels per acre less," White said.

White appreciates the guidance of applying the combination at the R3 stage because it controlled both fungal diseases and soybean aphids before they could be noticed nibbling away at yield. The tankmix of products was applied two to three weeks before neighbors started spraying for aphids, and White didn't have an aphid buildup. "Too many people think about having one shot to kill all the aphids with a contact insecticide, and they wait, wait and wait until damage has already been done before they spray," he said.

Another big success occurred with customers of the Cedar County Co-op at Tipton, Iowa, which treated about 3,600 acres with Stratego and Leverage 2.7 in 2009. "Each of our farmers thought they had a yield response," said Phil Petersen, co-op agronomist. "And there wasn't one of them that said it didn't pay."

Petersen said, "We'll probably come close to doubling the acres treated with Stratego and Leverage this year."

For more information about Stratego and Leverage 2.7, readers can contact Ifft and Byrum, respectively, at eric.ifft@bayercropscience.com and dave.byrum@bayercropscience.com.