The Buzz Around Biologicals in Corn and Soybeans

“The research had multiple N rates that span N rates above and below the optimal within a given field with and without the product,” says Dan Kaiser from the University of Minnesota, giving a synopsis of his work in the north central research. “A majority of the data shows the same yield no matter if you have the product or not.” Minnesota trials were conducted at six locations over the three-year study (2019-2022). Five locations show no yield benefit. The sixth at Waseca, Minnesota, in 2020 showed a 9 bu/acre yield benefit using Proven, which was equivalent to a 20 pounds of N per acre benefit to Proven. 

The north central region studies focused on yield, which is not the only benefit of biologicals as Pivot Bio and Corteva shared in their response to the research.

“At many trial locations summarized in the extension research studies, plots with Pivot Bio microbial products applied with reduced nitrogen rates achieved parity yield with the full-rate synthetic nitrogen check. This supports what we have told farmers all along – they can replace some of their synthetic nitrogen with Proven 40 and maintain yield,” says Nevins. 

“Corteva data supporting our yield improvement claims for Utrisha N [2.5 bu/acre in soybean and 5 bu/acre in corn] reflects a two-year, multilocation analysis of more than 300 field trials across U.S. corn-producing states. These university studies would need to include comparable levels of data — and be aggregated together — to account for the large number of uncontrolled environmental variables, such as pest pressures, weather conditions, soil factors including fertility, and manner of use or application,” says Eiberger.

What About Research Specifically for Soybeans?

Science for Success, a collaborative effort of soybean specialists across Extension in several states, conducted a study evaluating biological seed treatments in soybeans in 2022. The study spanned 17 states and 49 locations. There were nine treatments with a range of genus and species of microbial products as well as a control.

In summary of the research, Fabiano Colet, a doctoral candidate at The Ohio State University who is leading the project, shared that yield differences from biological seed treatments in soybeans ranged from –6.5 bu/acre to 4.5 bu/acre. When results were combined, there were no significant differences in yield by treatment. There was a higher probability of a positive yield response in the southern United States. 

“These are preliminary results,” he explains. “We know there is this trend in Southern states with particular products. We want to see if that’s going to happen again in 2023.” 

At the time of this writing, 2023 results were not yet available. When completed, results can be found at soybeanresearchinfo.com. This study is funded by the United Soybean Board and USDA.

Beck’s Hybrids has also researched biological products at multiple locations. Products were evaluated to determine the return on investment (ROI), and Beck’s labeled products with a positive ROI as Practical Farm Research (PFR) Proven. “PFR Proven products have a minimum of three years of data, multiple locations, have to provide a yield increase every year, and a positive average ROI over that period of testing,” says Travis Burnett, field agronomist with Beck’s Hybrids.

For 2022, PFR studies included nine biological products: seven corn products and two soybean products. The PFR biological products in corn offered a range in yield benefit of 3.3 to 9.8 bu/acre and a ROI range of $3.97 to $39.66. For soybeans, the yield benefit range was 1.1 to 1.4 bu/acre and ROI range of $1.99 to $13.07 per acre. For more information on these results, go to beckshybrids.com. 

When evaluating research results, Laura Lindsey, soybean and small grain specialist at The Ohio State University, recommends paying attention to statistical significance. 

“When we do field research, we need to distinguish between yield differences due to natural field variability (fertility, drainage, organic matter, etc.) versus yield differences due to a treatment (e.g., biological seed treatment). Our statistical analysis gives us a probability of response due to the treatment (vs. field variability). So, a probability value of 95% means we are 95% confident that the soybean yield is different due to the biological seed treatment,” explains Lindsey. “Most university research will include statistical comparison, but industry research may not. We encourage farmers to reach out to Extension when they see information about these products.”

Farmer Experiences

Anderson has four seasons of strip plot research on his farm looking at the returns in both yield and nitrogen cost savings. 

Anderson started his on-farm plot research with Proven 40, varying N rates from as high as 220 pounds down to 80 pounds. He has noted visible differences in growth some years. “In 2020, I noticed plants were darker green in the part of the field where Proven 40 was applied. It showed an 8-bushel advantage when we had heavy rain where there was leaching of N. That’s where this product is going to shine,” he says.

But what Anderson found most intriguing was the results from 2022 that included a pass with an 80-pound nitrogen rate. “I thought the 80 pounds of nitrogen would be a yellow streak out in the field, but it looked green and healthy. With 80 pounds of nitrogen and Proven 40, it yielded 218 bushels to the acre and without Proven 40 was 208,” he explains. 

Yield isn’t the only factor that Anderson considered. 

“In 2023, I had about 160 acres of tests. Strips included 120 pounds of N preplant with Proven 40 versus 160 pounds of N without Proven 40. There was about a 2-bushel yield increase for the Proven 40, but I was more impressed with the $35+ acre return when figuring reduced N and application costs,” explains Anderson.

Anderson is a believer in what his research has shown, and he now uses Proven 40 on all his corn acres.

Tips for On-Farm Research

“I think everyone should do their own research,” Anderson says. “I think you really have to replicate and be careful about how you set your plots up. If you don’t have good data, you aren’t going to make good decisions.” 

“If you are doing testing, make sure you set up your tests properly,” says Kaiser. “If you’re following the industry protocol where you have your rate, your rate minus 40 pounds N plus the product, don’t stop there. Do another strip with that minus 40 rate without the product. Then you’ll have that direct comparison at that reduced rate.” 

“I think the take home message from this is: If you are going to look at biologicals, what are their claims? What is its purpose? Is it for root growth, overall plant growth, nutrient related?” says Shaun Casteel, Extension soybean specialist at Purdue University. “Find the solution to a problem you are facing and put it in your worst case. I look at these as trying to be workhorses to help you with tools you need in your field. Put it to the test in those tough soils or disease pressure scenarios.” 

Soils are a complex and living biome and adding a biological to the system is more challenging than chemistry because so many more things interact. “The thing about a biological product is it’s so much harder to predict what’s going to happen since there are so many factors that can affect it once it gets into the soil itself,” explains Kaiser.