Menu

Benefits & Management of Crop Rotation

Crop rotation is a component of crop production and an implement for farm management, as it balances agronomy and economic market realities. From an agronomic perspective, crop rotation can increase nutrient cycling and nutrient use efficiency, decrease plant diseases and insect pests, assist in managing weeds, reduce soil erosion, and increase soil health. A common rotational system in many farming regions is corn followed by soybean for a two-year rotational program. Research at Iowa State University on extended multi-year rotations of three to four years found that although net economic returns did not differ between the cropping systems, corn and soybean yield potential increased, soil health improved, soil erosion decreased, herbicide and nitrogen (N) fertilizer use decreased, and some plant diseases were reduced.(1)

Managing Risk with Crop Rotation
Crop rotation can help reduce the risk of adverse environmental stress, such as drought, early frost, and wet springs that result in a delayed planting window. It can help reduce the risk of an economically significant infestation of insects that are specific to a crop for a part of their life cycle, such as the corn rootworm complex and soybean aphid. Most foliar plant diseases are also specific to a certain crop species and, therefore, rotation can help reduce the risk of economic loss as the result of plant diseases such as Northern corn leaf blight, brown stem rot of soybean, and tar spot in corn.

The cropping sequence of the rotational system should also be considered, as certain sequences may be detrimental and increase disease risk. For example, corn grown before wheat can increase the incidence of fusarium head blight (wheat scab) in wheat. Additionally, there are some root and crown diseases of wheat that can also increase in incidence in a corn-wheat rotation system, as corn can be infected by some wheat diseases as well.2 A tool to assist in determining the economic returns from a corn-soybean and a corn-soybean-wheat rotation has been developed at the University of Illinois and is available at https://farmdoc.illinois.edu/fast-tools/planting-decision-model.

Managing Resources with Crop Rotation
Crop rotation can help increase environmental resource use and producer time efficiency. Water use rates can be very different between crops. For example, corn is considered a high water-use crop compared to wheat and soybean.2 Therefore, after drought, a crop with a lower water use rate should follow corn in rotation if soil moisture is not restored to full capacity during the off season.

Crop rotation can improve time management as well, as it allows farmers to spread the workload over a longer time. Equipment and labor can be more efficiently used because different crops are planted, managed during the growing season, and harvested at different times.

Managing Weeds with Crop Rotation
Many weed management plans include crop rotation as a tactic. A single crop in a continuous cropping system can become infested with a weed species that has adapted to the crop being grown and the management system being used. Alternatively, a diverse crop rotation changes the weeds’ environment. The changing environmental conditions prevent any one weed species from becoming dominant, which helps to prevent the overreliance on a single herbicide that can lead to herbicide resistance in weeds.

A survey of the scientific literature indicated that crop rotation resulted in lower weed densities in 21 cases, higher weed densities in 1 case, and equal weed densities in 5 cases compared to continuous cropping of a single crop. In 12 studies, the weed seed bank density was also reported for crop rotation and continuous cropping systems. In these studies, the weed seed bank density was lower with crop rotation in 9 cases and equivalent in 3 compared to continuous cropping.(3)

Carbon Sequestration with Crop Rotation
In a long-term study in Illinois, a continuous corn production system lost about 30% of the soil carbon when compared to a corn-oats-clover rotation system. However, recent studies have indicated that the tillage system, specifically no-till systems, in conjunction with crop rotation can play a major role in maintaining or increasing soil carbon content.(4)

Final Thoughts Using cover crops is also a way to introduce diversity into the cropping system. Please see the Bayer ForGround Resource Library for more information adding cover crops into your cropping rotation.

Here are some things farmers should consider when deciding whether to add a rotational crop into their cropping system.

• Do I have a market for the crop I am adding to the rotation?
• Is the crop a grass or broadleaf, which would have implications for the herbicide program?
• Is the crop an annual, biennial, or perennial?
• Is the crop a cool-season plant or a warm-season plant?
• Does the seeding date require a fall seeded, early spring, or late spring planting window?
• Is the crop harvested once during the growing season or multiple times?
• What are the fertility and pH requirements of the rotational crop?
• Will my equipment match up with the what the crop requires for planting, maintenance, and harvesting?

Article Link

Sources:
1 Liebman, M.Z., Chase, C.A., Johanns, A.M., Sundberg, D.N. 2013. Agronomic and economic performance of three crop rotation systems in Central Iowa. Iowa State Research Farm Progress Reports. 1889. https://lib. dr.iastate.edu/farms_reports/1889/.
2 Beck, R. 2021. Crop rotation in farm management. South Dakota State University Extension. https://extension.sdstate.edu/crop-rotation-farm-management.
3 Liebman, M. and Dyck, E. 1993. Crop rotation and intercropping strategies for weed management. Ecological Applications. 3:92-122. https://doi.org/10.2307/1941795
4 Al-Kaisi, M. 2008. Impact of tillage and crop rotation systems on soil carbon sequestration. Iowa State University Extension. https://store.extension.iastate.edu/product/5453
Legal Statements
Performance may vary, from location to location and from year to year, as local growing, soil and weather conditions may vary. Growers should evaluate data from multiple locations and years whenever possible and should consider the impacts of these conditions on the grower’s fields. Bayer and Bayer Cross are registered trademarks of Bayer Group. All other trademarks are the property of their respective owners. (c)2023 Bayer Group. All rights reserved. 1211_70389

An Inside Look at Reduced Stature Corn

*This content was previously published by Corteva Agriscience.

The adage “what’s old is new again” is applicable when plant breeders, researchers, agronomists and farmers talk about the possibilities reduced stature corn may bring. The hybrids may be new, but the breeding process to shorten plant stature is not. Corteva Agriscience researchers are striving to develop reduced stature corn with stronger stalks and an agronomic system that potentially allows for more yield per acre. Reduced stature plant breeding was developed with wheat genetics by world-renowned agronomist Norman Borlaug, in the mid-1950s. That successful work was later duplicated with rice, dramatically increasing yields in both crops.

Though this concept has been viable since Borlaug and his teams completed their work, it has been slow to gain broad application in corn hybrids. This doesn’t mean research has been lacking. Far from it.

Cory Christensen is the Corn Pipeline Development Leader at Corteva Agriscience. His job is to shape new product concepts in the corn pipeline from ideation or inception, and shepherd them through each stage of the development process until they’re ready to launch.

“Reduced stature corn is not a new idea, but interest in it has quickly picked up steam,” Christensen says. “Over the past 10 years, we have carefully analyzed a number of different genetic approaches to make corn plants shorter, and our researchers have identified one of those trait approaches that had the characteristics we desired.

“We were gaining confidence in this trait at the same time the big wind events hit the Midwest in 2020 and 2021,” he continues. “Since we have a native allele version of the trait, we are well-positioned to develop and launch a set of hybrid products to introduce the concept to the market. Hybrids demonstrated excellent resilience under high winds with our trait, and we are confident that growers will realize that benefit among others.”

Christensen is quick to point out other advantages of reduced stature corn include easier ground access for equipment to apply fertilizers and other inputs. Specific management recommendations are in development.

 

Delivering value to farmers is the reason for new hybrid development

The initial hybrid products containing the reduced stature trait are under evaluation and are expected to be on the market later this decade.

“Our goal is to give growers opportunities to experience these products and see if they perform like we expect they will,” Christensen says. “Most importantly, they must deliver value on customers’ operations just as any hybrid we release does.

“It’s important to understand we are following our normal product development process,” he adds. “We’re approaching this just like we do with other hybrids. We’ve taken some of our new, pre-commercial inbreds, the parents of future hybrid seed products, and converted them to reduced stature inbreds with our trait. These new potential hybrid products are working their way through our product characterization trials.”

Product characterization trials take place throughout corn-growing regions for at least two years before any new hybrid is launched. Product development teams want to observe genetic and environmental interactions so there is solid confidence in recommendations to growers. In addition, they’re evaluating performance at various densities and will have sound recommendations about planting densities upon launch.

 

Reduced stature corn offers beneficial new technology

Corteva researchers must address how to define the reduced stature corn concept, understand its genetics, ensure data is correct as well as how to characterize the product and launch it. They must also consider what the genetics and long-term plant breeding program looks like.

“When you think of all the mechanical advances, chemical advances and technological advances, I look at reduced stature corn as another piece of technology that happens
to be genetic technology,” Brandon Wardyn, Evaluation Zone Lead, Corteva Agriscience, says.

“It changes some physics of the plant, so this changes how we need to breed for different traits, namely traits associated with tolerating wind. Given this new level of standability, it can really open up the genetic space we can operate in. A basic principle in plant breeding is as you take pressure off one trait, you can apply it to a different trait.”

Looking at the history of corn breeding, researchers were able to get plants to silk and shed pollen in relative synchrony. This was a bigger issue 30 years ago than it is now, as breeding has solved it. Today, breeders will be doing similar things with reduced stature corn.

“Reduced stature corn is going to open what I call the ‘agronomic playbook,’” Wardyn says. “It is going to allow us to go back and reevaluate some basic agronomic principles and let us look at how we can improve them to get higher yields.

“The rate the industry and growers are successful at this will determine if or how fast reduced stature corn becomes the norm. The potential is there, but there are still a lot of ifs to consider,” he notes.

 

Testing in progress

There is considerable acreage of reduced stature corn in testing and it’s growing.

“I’m proud of the process we have,” Wardyn says. “Yes, we want to deliver reduced stature corn, but the overriding principle is that it has to be right for our customers. We can’t put any customer at risk and we’re not going to do that. When we launch a product, we’ll do it in a way that helps a customer become more profitable. Plus, we’ll promote it by sharing its strengths and weaknesses. This line of thinking is a purposeful part of every meeting we have across all team members.”

He notes that reduced stature corn will not require a significant “change of iron” by any customer, nor will it require a massive shift in how they operate equipment.

“As we start to open up the agronomic playbook, I think this is where it’ll get fun for some folks when we start to optimize practices that are going to be different depending on where a customer operates,” Wardyn says. “It may mean a different row configuration, a different fertility program or a lot of things. These practices will develop over time and it’s going to be amazing to watch.

“I consider the ag industry advanced and technologically savvy and when you see an industry get a technology that has the potential to change what has been thought of as basic agronomy and really change those principles, it’s going to be fun. It certainly doesn’t happen every day,” he adds.

Some things will remain the same. Reduced stature corn is still corn with genetics similar to conventional corn. There will be ways farmers can optimize it whether through fertility, fungicides or perhaps pesticides. Thus, expectations are now that standard practices will be adequate to grow a profitable crop.

“As a corn breeder, the most exciting thing for me with reduced stature corn is, in theory, we’ll be able to take some selection pressure off some agronomic traits that are important in tall corn, such as wind traits and stalk lodging,” Wardyn says.

“Historically those are the biggest yield limiters. So, when we launched a product before, all those boxes had to be checked. With reduced stature corn, we can’t ignore those traits but we can take some selection pressure off. It’s exciting for me to think about where yield can go when you unlock agronomic restrictions and unlock genetic potential. It’s like new tools showed up we never had before.”

 

What farmers can expect

The trait Corteva breeders selected to shorten the corn does so uniformly. Christensen says to expect plant height reduced by about 30% and ear height by about 25%.

There are two questions Christensen gets asked a lot when talking to growers about reduced stature corn. One is about ear height and whether it will get too low for harvest and the other is how the trait holds up against the variety of standability concerns — brittle snap, stalk lodging, root lodging and others. “In all the studies with different genetics and different environments we have done so far, our ears on hybrids are consistently above the 24-inch combine header threshold and we have observed excellent improvement in standability under artificial and natural wind treatments. We’re pleased with how the reduced stature hybrids address these challenges to date.”

“We’ll soon have reduced stature corn in demonstration plots throughout the country for growers to see,” Wardyn says. “They’ll be set up in ways to generate discussion, get a hands-on look and ask questions of local experts who’ll be on hand.

“Before we launch, we’ll have a full data set, just like we do on any new hybrid we have now. I tell folks it is going through the Corteva corn hybrid evaluation process just like every other Corteva hybrid has done. I’m proud of the robustness of characterization we put them through. It’s hard to make it through the evaluation.”

Wardyn sums up the best part about reduced stature corn.

“If you’re good at growing tall corn, you’re going to be good at growing reduced stature corn.”

Article Link

™ ® Trademarks of Corteva Agriscience and its affiliated companies. © 2024 Corteva.

 

Impact of Corn Hybrids with Multiple Traits

*This content was previously published by Corteva Agriscience.

PEST PROBLEMS IN CORN

Corn crops face several pest challenges from insects, weeds and even volunteer corn. There can be multiple ways to deal with these pressures, including incorporating integrated pest and/or weed management programs. However, attention also needs to be paid to the potential for weed and insect resistance. Left unchecked, insects like corn earworm and European corn borer can damage yields, with declines of up to 25% from corn borer presence.1 Weeds like waterhemp and marestail can take 5-20% and 32% of corn yield, respectively.2,3 Highly competitive volunteer corn can reduce yields by 13% in corn fields while encouraging western corn rootworm and gray leaf spot disease in later crops.

 

INTRODUCTION OF BIOTECHNOLOGY TRAITS

The 1996 release of herbicide-tolerant corn and hybrids with protection against European corn borer changed farming practices. Corn traits these days have built upon those foundations, allowing for the use of additional herbicides and protecting against more insects. Traits help protect yields against damage caused by pests — following their adoption corn yields have improved by about two bushels per acre annually, which is a bigger and more consistent improvement than what farmers had experienced previously.

Although hybrids with multiple traits may be more expensive than conventional hybrids, they can provide overall savings in terms of management, labor and fuel costs — especially when fuel prices are high or in areas where finding on-farm workers is a challenge. Yields also tend to be more consistent, especially when using corn hybrids with multiple stacked traits, according to data from the Wisconsin Corn Hybrid Performance Trials.

 

ADDRESSING WEED RESISTANCE WITH MULTIPLE MODES OF ACTION

Since the release of glyphosate-tolerant corn and the reliance on just one weed control method for so many years, 48 weed species have developed resistance.6 Bringing new traits to market takes a long time, which heightens the importance of employing an integrated weed management program that uses multiple tools — including row spacing, mechanical practices and incorporating herbicides with multiple, different modes of action.

Corn hybrids with tolerance to multiple herbicides allow for the use of more modes of action against weeds and extend the lifetime of these herbicides by delaying the development of resistance. For example, planting PowerCore® Enlist® corn provides tolerance to four herbicides, including 2,4-D choline, glyphosate, glufosinate and FOPs. Glufosinate and 2,4-D choline can help manage late-season broadleaf weeds and 2,4-D choline can be sprayed on PowerCore Enlist corn up to 30″ without causing damage. Having access to multiple modes of action also helps farmers address glyphosate-resistant grasses — including volunteer corn. Planting PowerCore Enlist corn, which is tolerant to FOPs, provides a way to control resistant grasses and volunteer non-Enlist® corn in Enlist corn fields with options like Assure II herbicide.

 

CONCLUSION

There is a selection of tools available to farmers seeking to control weeds and insects in corn fields. However, as weeds and insects develop resistance to chemical control products, making the best use of integrated programs helps protect yield potential and supports the use of current control methods into the future. Planting corn hybrids with tolerance to herbicides with multiple modes of action — like PowerCore Enlist corn — can be one way to help farmers manage weeds and pests.

Article Link

1 Myers, Scott, Michael Ballweg, and John Wedberg. “Assessing the Impact of European Corn Borer on Corn Grown for Silage,” Focus on Forage 3, no. 3(2000).
2 Hartzler, Bob, and Dawn Nordby. “Influence of Corn on Waterhemp Growth,” Iowa State University Extension and Outreach: Integrated Crop Management. Accessed September 1, 2022. https://crops.extension.iastate.edu/encyclopedia/influence-corn-waterhemp-growth.
3 Soltani, Nader, Christy Shropshire, and Peter Sikkema. Control of glyphosate-resistant horseweed (Conyza canadensis) with tiafenacil mixes in corn.” Weed Technology 35, no. 6 (2021): 908-911 https://doi.org/10.1017/wet.2021.44.
4 Chalal, Parminder, and Amit Jhala. “Control of Glyphosate-Resistant Volunteer Corn in LibertyLink Soybean.” Cropwatch. Updated June 12, 2017. https://cropwatch.unl.edu/2017/control-glyphosate-resistant-volunteer-corn-liberty-link-soybean.
5 Gullickson, Gil. “Are Traits Worth the Expense?” Successful Farming March 10, 2017. Accessed September 1, 2022. https://www.agriculture.com/are-traits-worth-the-expense.
6 Baek, Yousoon, Lucas Bobadilla, Darci Giacomini, Jacob Montgomery, Brent Murphy, and Patrick Tranel. “Evolution of Glyphosate-Resistant Weeds.” Reviews of environmental contamination and toxicology vol. 255 (2021): 93-128.doi:10.1007/398_2020_55.
7 Blois, Matt. “Following several fallow decades, herbicide companies are searching for new modes of action.” C&EN 100 no 22, June 17, 2022. https://cen.acs.org/environment/pesticides/crop-protection-herbicide-mode-action-glyphosate/100/i22.
8 Hartzler, Robert, and Prashant Jha. “2021 Herbicide Guide for Iowa Corn and Soybean Production.” Iowa State University Extension and Outreach. Updated February 2021.
™ ® Trademarks of Corteva Agriscience and its affiliated companies. The transgenic soybean event in Enlist E3® soybeans is jointly developed and owned by Corteva Agriscience and M.S. Technologies L.L.C. Enlist Duo® and Enlist One® herbicides are not registered for sale or use in all states or counties. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your area. Enlist Duo and Enlist One are the only 2,4-D products authorized for use with Enlist crops. Consult Enlist herbicide labels for weed species controlled. POWERCORE® multi-event technology developed by Corteva Agriscience and Monsanto. POWERCORE® is a registered trademark of Monsanto Technology LLC. Always follow IRM, grain marketing and all other stewardship practices and pesticide label directions. Bt products may not yet be registered in all states. Check with your seed representative for the registration status in your state. Assure® II herbicide is currently the only FOP herbicide for in-crop use with Enlist® corn. Assure II herbicide (quizalofop) is a Group 1 herbicide for grass control. Product responses can vary by location, pest population, environmental conditions, and agricultural practices. Please contact your Corteva Agriscience sales professional for information and suggestions specific to your operation. Individual results may vary. Various factors, including pest pressure, reduced susceptibility, and insect resistance in some pest populations may affect efficacy of certain corn technology products in some regions. To help extend durability of these technologies, Corteva Agriscience recommends you implement integrated pest management (IPM) practices such as crop rotation, cultural and biological control tactics (including rotating sources of Bt-protected corn traits), pest scouting, and appropriate use of pest thresholds when employing management practices such as insecticide application. You must also plant the required refuge when using these technologies. Please contact your sales professional or consult with your local university extension for more information regarding insect resistance management guidelines, best management practices and to understand whether there has been a shift in susceptibility or insect resistance with certain pests documented in your area. Bexfond™ biological fungicide, Hearken™ biological insecticide, Sosdia Stress abiotic stress mitigator, Sosdia Stress Plus abiotic stress mitigator and Utrisha™ N nutrient efficiency optimizer are not for sale or use in all states. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your state. Liberty®, LibertyLink® and the Water Droplet Design are trademarks of BASF. Always read and follow label directions. © 2024 Corteva. Groundwork – March 2024

Corn Seed Size

 

Is there a difference in germination across corn seed sizes?

A study was conducted by the University of Wisconsin using small rounds, small flats, large rounds, and large flats of two hybrids with two tillage systems (no-till and conventional tillage) and two planting dates (early and late). Under early planting with soil crusting and no-till conditions, the emergence of small rounds ranged from 5 to 15% lower than that of small flats or large rounds. While the no-till system resulted in slower emergence that delayed early growth and silking, which resulted in reduced grain yield, seed size was irrelevant and did not have an impact on the final yield. In another study conducted by the University of Guelph, results showed that under ideal conditions seed size did not influence emergence; however, plants from small seed tended to have a shorter final height.

 

Does seed size influence seedling vigor?

Generally, vigor of seedlings from large flat kernels (from the middle of the ear) exceeds the vigor of seedlings from small (from ear tip) and large (from ear base) round kernels. Seedlings from larger seeds have higher weights and are consequently larger. These differences in vigor and size are particularly important if planting is occurring at deeper than normal planting depths. While smaller seeds may have less vigorous plants in the vegetative stages, by the beginning of the reproductive stages the differences are negligible.

 

What are the advantages and disadvantages of different corn seed sizes?

While larger seeds may have the advantage over small seeds when planted early in colder soil temperatures, smaller seeds can germinate faster
in dry soils because they need less water to initiate germination.

 

Does seed size impact final yield potential?

The research suggests that seed size does not impact final yield when plant populations are the same. Therefore, the most important aspect of obtaining the highest yield potential of a given corn product is achieving the optimal plant population for that product, not selecting the seed size that
is planted.

 

Article Link

Sources:
Graven, L.M. and Carter, P.R. 1990. Seed size/shape and tillage system effect on corn growth and grain yield. Journal of Production, Agriculture, 3:445-452.
Hunter, R.B. and Kannenberg, L.W. 1972. Effects of seed size on emergence, grain yield, and plant height in corn.
Canadian Journal of Plant Science, 52:252-256. https://cdnsciencepub.com/doi/pdf/10.4141/cjps72-040
El-Abady, M.I. 2015. Influence of maize seed size/shape, planted at different depths and temperatures on seed emergence and seedling vigor. Research Journal of Seed Science. 8:1-11. http://docsdrive.com/pdfs/academicjournals/rjss/2015/1-11.pdf
Peterson, J.M., Perdomo, J.A., and Burris, J.S. 1995. Influence of kernel position, mechanical damage and controlled deterioration on estimates of hybrid maize seed quality. Seed Science and Technology. 23:647-657.
Elmore, R. and Abendroth, L. 2005. Do corn kernel size and shape really matter? University of Nebraska Extension.
Crop Watch, 2005-5:47. https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1290&context=cropwatch
Chaudhry, A.U. and Ullah, M.I. 2001. Influence of seed size on yield, yield components and quality of three maize genotypes. OnLine Journal of Biological Sciences. 1: 150-151. https://scialert.net/fulltext/fulltextpdf.php?pdf=ansinet/jbs/2001/150-151.pdf
Legal Statements
ALWAYS READ AND FOLLOW PESTICIDE LABEL DIRECTIONS. Performance may vary, from location to location and from year to year, as local growing, soil and environmental conditions may vary. Growers should evaluate data from multiple locations and years whenever possible and should consider the impacts of these conditions on their growing environment. The recommendations in this material are based upon trial observations and feedback received from a limited number of growers and growing environments. These recommendations should be consid-ered as one reference point and should not be substituted for the professional opinion of agronomists, entomologists or other relevant experts evaluating specific conditions. Bayer and Bayer Cross are registered trademarks of Bayer Group. All other trademarks are the property of their respective owners. ©2023 Bayer Group. All rights reserved. 1214_110452.

Corn Seed Size

 

Is there a difference in germination across corn seed sizes?

A study was conducted by the University of Wisconsin using small rounds, small flats, large rounds, and large flats of two hybrids with two tillage systems (no-till and conventional tillage) and two planting dates (early and late). Under early planting with soil crusting and no-till conditions, the emergence of small rounds ranged from 5 to 15% lower than that of small flats or large rounds. While the no-till system resulted in slower emergence that delayed early growth and silking, which resulted in reduced grain yield, seed size was irrelevant and did not have an impact on the final yield. In another study conducted by the University of Guelph, results showed that under ideal conditions seed size did not influence emergence; however, plants from small seed tended to have a shorter final height.

 

Does seed size influence seedling vigor?

Generally, vigor of seedlings from large flat kernels (from the middle of the ear) exceeds the vigor of seedlings from small (from ear tip) and large (from ear base) round kernels. Seedlings from larger seeds have higher weights and are consequently larger. These differences in vigor and size are particularly important if planting is occurring at deeper than normal planting depths. While smaller seeds may have less vigorous plants in the vegetative stages, by the beginning of the reproductive stages the differences are negligible.

 

What are the advantages and disadvantages of different corn seed sizes?

While larger seeds may have the advantage over small seeds when planted early in colder soil temperatures, smaller seeds can germinate faster in dry soils because they need less water to initiate germination.

 

Does seed size impact final yield potential?

The research suggests that seed size does not impact final yield when plant populations are the same. Therefore, the most important aspect of obtaining the highest yield potential of a given corn product is achieving the optimal plant population for that product, not selecting the seed size that is planted.

Article Link

Sources:
Graven, L.M. and Carter, P.R. 1990. Seed size/shape and tillage system effect on corn growth and grain yield. Journal of Production, Agriculture, 3:445-452.
Hunter, R.B. and Kannenberg, L.W. 1972. Effects of seed size on emergence, grain yield, and plant height in corn.
Canadian Journal of Plant Science, 52:252-256. https://cdnsciencepub.com/doi/pdf/10.4141/cjps72-040
El-Abady, M.I. 2015. Influence of maize seed size/shape, planted at different depths and temperatures on seed emergence and seedling vigor. Research Journal of Seed Science. 8:1-11. http://docsdrive.com/pdfs/academicjournals/rjss/2015/1-11.pdf
Peterson, J.M., Perdomo, J.A., and Burris, J.S. 1995. Influence of kernel position, mechanical damage and controlled deterioration on estimates of hybrid maize seed quality. Seed Science and Technology. 23:647-657.
Elmore, R. and Abendroth, L. 2005. Do corn kernel size and shape really matter? University of Nebraska Extension.
Crop Watch, 2005-5:47. https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1290&context=cropwatch
Chaudhry, A.U. and Ullah, M.I. 2001. Influence of seed size on yield, yield components and quality of three maize genotypes. OnLine Journal of Biological Sciences. 1: 150-151. https://scialert.net/fulltext/fulltextpdf.php?pdf=ansinet/jbs/2001/150-151.pdf
Legal Statements
ALWAYS READ AND FOLLOW PESTICIDE LABEL DIRECTIONS. Performance may vary, from location to location and from year to year, as local growing, soil and environmental conditions may vary. Growers should evaluate data from multiple locations and years whenever possible and should consider the impacts of these conditions on their growing environment. The recommendations in this material are based upon trial observations and feedback received from a limited number of growers and growing environments. These recommendations should be consid-ered as one reference point and should not be substituted for the professional opinion of agronomists, entomologists or other relevant experts evaluating specific conditions. Bayer and Bayer Cross are registered trademarks of Bayer Group. All other trademarks are the property of their respective owners. ©2023 Bayer Group. All rights reserved. 1214_110452.

Considerations for Corn Product Selection

Considerations for Selecting Corn Products Enhanced with Biotechnology

Since 1996, corn production has benefited from biotechnological traits and associated agronomic practices. Insect and herbicide tolerance traits placed into highly productive corn genetic lines have steadily increased yield potential while reducing pest and environmental stresses. Helping to maximize corn product yield potential and farm profitability is one of the greatest potential benefits from genetically modified (GM) corn products.

The results from a comprehensive review of 21 years of world-wide research data on GM products, conducted by researchers at the University of Pisa in Italy, showed GM corn products:

Trials have also shown that other benefits from certain GM corn products may include increased planting rates, which have the potential to increase yield and allow for more effective use of continuous corn.

 

Trait Benefits for Weed Management

Early-season weeds, such as common waterhemp, aggressively compete for nutrients and water that young corn plants need to help maximize yield potential (Figure 1). Herbicide resistant traits such as Roundup Ready® 2 Technology and LibertyLink® allow for the use of glyphosate only and glufosinate only herbicides, respectively. Corn products stacked with both of these traits can help reduce the potential for the development of herbicide resistance by alternating chemistries.

Corn products with Roundup Ready® 2 Technology provide proven crop safety, over-the-top application flexibility of Roundup® brand glyphosate only agricultural herbicides, and broad spectrum weed control. Overall benefits of timely weed control have shown:

 


Figure 1. Without management, common waterhemp can quickly compete with seedling corn for nutrients and water.

 

Trait Benefits for Insect Management

Feeding from European corn borer (ECB), corn earworm, western bean cutworm, fall armyworm, and corn rootworm can reduce yield and may allow pathogens to infect, multiply, and produce mycotoxins which have the potential to cause health problems in animals and humans.3,4,5 Corn products protected with insect-specific Bacillus thuringiensis (B.t.) events or RNAi technology protect the plant tissues (stalks, grain, roots) on which these insects feed, reducing the risk of lost yield or lower grain quality. Soil-applied and foliar insecticides can be used to help manage labeled insects; however, insecticide applications require precise application timing, proper rates, adequate coverage, and may affect beneficial insects, such as lady beetles. Additionally, insecticide efficacy can diminish quickly and leave plants vulnerable.

The average yield loss of one ECB per plant has been estimated at 5%.6 The loss can be a combination of stress caused by vascular tunneling (loss of nutrients and water), lodging, ear damage, and non-harvestable dropped ears. At current corn prices of around $6.00/bu, a 5% yield loss on 200 bu/acre corn is an economic impact of $60.00/acre (a $30,000 hit on 500 acres). The financial impact can increase if additional corn borers are present.

Protecting corn roots from corn rootworm feeding can have agronomic benefits in addition to insect management. Improved root growth and activity can allow plants to export more cytokinins from the roots and utilize nitrogen more effectively after flowering to promote higher kernel weight and yield potential. A Bayer Learning Center trial at Monmouth, Illinois in 2020 compared B.t. rootworm protected corn products against a non-B.t. protected corn product. The five B.t. corn rootworm protected corn products had an average yield of 199.9 bu/acre compared to the non-protected average yield of 171.5 bu/acre. The 28.4 bu/acre gain at $6.00/bu results in an extra $170.40/acre.

 


Figure 2. Corn root showing feeding damage from corn rootworms.

 

Root protection from corn rootworms is getting bolstered with RNAi technology or RNA-interference, a non-B.t. mode of action. SmartStax® PRO with RNAi Technology is the first registered product to use ribonucleic acid interference (RNAi) to help protect against corn rootworm. It has the ability to shut down, or interfere with, the DvSnf7 mechanism, that allows rootworms to produce an essential protein. Without this protein, the corn rootworm larvae cannot survive (Figure 3). SmartStax® PRO Technology is the next generation of corn rootworm protection, and the first product offering three modes of action for corn rootworm control.

 


Figure 3. Graphic of how RNAi technology controls corn rootworm.

 

Corn yields have increased through the years in part because of improved genetics, trait technology, and higher planting rates. An evaluation of 948 GM and 1250 conventional corn products from University of Wisconsin data for the years 1990 to 2010 showed GM corn products exhibited higher yields with higher seeding rates compared to the conventional corn products.2 Corn products with B.t. demonstrated a 6.6% increase in yield and 22% decrease in lodging compared to non-B.t. products.

Continuous corn operations are likely to experience increased insect and disease pressure compared to rotational corn operations because insects and pathogens have the potential to continuously reside in the soils and crop residue. Corn products with specific insect B.t. protection can help reduce the impact that corn rootworms and European and Southwestern corn borers can have in continuous corn. A University of Wisconsin continuous corn study in 2000 showed that farmers planting GM corn products had the potential for an increased opportunity for higher yields compared to conventional corn products.

 

Summary

The planting of GM corn products with herbicide resistance and multiple mode of action insect protection traits and RNAi technology along with intensive management have shown the potential to help farmers maximize the genetic potential of the products planted. The PG Economics annual report on the impact of GM crops shows that GM crops are credited with decreasing pesticide and fuel use, facilitating conservation tillage practices that reduce soil erosion, improving carbon retention, and lowering greenhouse gas emissions.

If non-B.t. corn is the planned option to plant, the crop should be scouted for insect activity and managed accordingly if an infestation has reached an economic threshold to help protect yield potential. University Extension Offices generally have procedures for scouting insects such as European corn borer and corn rootworm.

 

Article Link

 

Sources:
Pellegrino, E., Bedini, S., Nuti, M., and Erocli, L. 2018. Impact of genetically engineered maize on agronomic, environmental and toxicological traits: a meta-analysis of 21 years of field data. Scientific Reports.
Chavas, J., Shi, G., and Lauer, J. 2014. The effects of GM technology on maize yield. Crop Sci. 54:1331-335.
National Research Council. 2010. The impact of genetically engineered crops on farm sustainability in the United States. National Academies Press.
Folcher, L., Delos, M., Marengue, E., Jarry, M., Weissenberger, A., Eychenne, N., and Regnault-Roger, C. 2010. Lower mycotoxin levels in Bt maize grain. Agron. Sustain. Dev. 30:711-719.
Hutchison, W.D. 2010. Areawide suppression of European corn borer with Bt maize reaps savings to non-Bt maize growers. Science 330:222-225.
Hammond, R.B., Michel, A., and Eisley, J.B. 2014. European corn borer. Agriculture and Natural Resources Fact Sheet. ENT-15-14. Ohio State University Extension. The Ohio State University. https://aginsects.osu.edu/. 7Haegle, J.W. and Below, F.E. 2013. Transgenic corn rootworm protection increases grain yield and nitrogen use of maize. Crop Science 53:585-594.
Comparing corn rootworm trait platforms. 2020. Bayer Group. https://www.cropscience.bayer.us/-/media/Bayer-CropScience/ Country-United-States-Internet/Documents/Learning-Center/Monmouth/2020-2021/Comparing-Corn-Rootworm-Trait-Platforms. ashx.
Stranger, T.F. and Lauer, J.G. 2006. Optimum plant populations of Bt and non-bt corn in Wisconsin. Agron. J. 98:914-921 (2006). American Society of Agronomy. Madison, Wisconsin.
Brookes, G. 2022. GM Crops: global socio-economic and environmental impacts 1996-2020. PG Economics Ltd, UK. https://pgeconomics.co.uk/.
Dean, A. and Hodgson, E. 2020. Planted non-Bt corn? Plan to scout for European corn borer. Integrated Crop Management. ICM News. Iowa State University Extension and Outreach. Iowa State University. https://crops.extension.iastate.edu/cropnews/2020/06/planted-non-bt-corn-plan-scout-european-corn-borer/.
Hodgson, E. 2020. Scouting for corn rootworm larvae. Integrated Crop Management. Blog Post. Iowa State University Extension and Outreach. Iowa State University. https://crops.extension.iastate.edu/blog/erin-hodgson/scouting-corn-rootworm-larvae/.
Web sites verified 12/5/2022.
Legal Statements
Bayer is a member of Excellence Through Stewardship® (ETS). Bayer products are commercialized in accordance with ETS Product Launch Stewardship Guidance, and in compliance with Bayer’s Policy for Commercialization of Biotechnology-Derived Plant Products in Commodity Crops. Commercialized products have been approved for import into key export markets with functioning regulatory systems. Any crop or material produced from this product can only be exported to, or used, processed or sold in countries where all necessary regulatory approvals have been granted. It is a violation of national and international law to move material containing biotech traits across boundaries into nations where import is not permitted. Growers should talk to their grain handler or product purchaser to confirm their buying position for this product. Excellence Through Stewardship® is a registered trademark of Excellence Through Stewardship. ALWAYS READ AND FOLLOW PESTICIDE LABEL DIRECTIONS. B.t. products may not yet be registered in all states. Check with your seed brand representative for the registration status in your state. IMPORTANT IRM INFORMATION: RIB Complete® corn blend products do not require the planting of a structured refuge except in the Cotton-Growing Area where corn earworm is a significant pest. See the IRM/Grower Guide for additional information. Always read and follow IRM requirements. Performance may vary, from location to location and from year to year, as local growing, soil and weather conditions may vary. Growers should evaluate data from multiple locations and years whenever possible and should consider the impacts of these conditions on the grower’s fields. Roundup Ready® 2 Technology contains genes that confer tolerance to glyphosate. Glyphosate will kill crops that are not tolerant to glyphosate. Tank mixtures: The applicable labeling for each product must be in the possession of the user at the time of application. Follow applicable use instructions, including application rates, precautions and restrictions of each product used in the tank mixture. Not all tank mix product formulations have been tested for compatibility or performance other than specifically listed by brand name. Always predetermine the compatibility of tank mixtures by mixing small proportional quantities in advance. Herculex® is a registered trademark of Dow AgroSciences LLC. LibertyLink® and LibertyLink® and the Water Droplet Design® are trademarks of BASF Corporation. Respect the Refuge and Corn Design® and Respect the Refuge® are registered trademarks of National Corn Growers Association. Bayer, Bayer Cross, RIB Complete®, Roundup Ready 2 Technology and Design™, Roundup Ready® and SmartStax® are trademarks of Bayer Group. All other trademarks are the property of their respective owners. ©2023 Bayer Group. All rights reserved. 1210_19048

Planter Adjustments for Size & Weight Differences for Corn Seed

There are many adjustments that can be made to a corn planter to accurately place the seed in the seed slice, to maximize the yield potential of the seed product.

Seed Size and Yield Potential

Varying environmental conditions may result in a variety of seed sizes and shapes from the same corn product. Seed size is also affected by corn product genetics and growing conditions, especially during the pollination and grain fill period. Typically, large rounds come from the base of the ear, flats from the center, and small flats and small rounds from the tip (Figure 1). Plateless seed usually comes from the base or the ear or the tip. Regardless of size or shape, all seeds from the same ear and from the same plant have the same genetic material, and thus the same genetic yield potential.

Though genetic yield potential is not affected by seed size, there can be differences in germination related to seed size under adverse planting conditions. Large seed can have slightly decreased emergence rates in dry soil conditions because large seed requires more moisture to germinate, compared to small seed. Small seed can have slightly decreased emergence in cool or crusted soils because the energy needed for emergence in these environments may be greater than the amount stored in the endosperm. The differences noted in early growth related to seed size are usually not apparent after tasseling. Similar silking dates and grain yield are expected when emerged plant populations are the same regardless of seed size and shape.

Figure 1. Seed size and shape on a corn ear varies from large rounds (left, ear base), flats (middle of ear), to small rounds (ear tip).

Seed Weight

It is becoming more common for seed companies to sell seed based on seed count along with seed size and shape. Historically, farmers often purchase specific seed weights or seed sizes based on how their planter was configured. Today producers more often prefer to purchase seed that is consistent in bag weight to reduce the number of adjustments needed when changing from seed lot to seed lot or when changing corn products during the planting season. This information is located on the seed tag or the seed bag and will help a producer adjust the planter for optimum performance.

The seed size rating scale that Bayer uses to help producers understand the different size and shape that is given to each corn product during the screening and bagging process includes:

Different seed sizes are described along with the seed treatment, seeds per pound and the corn seed bag weight for 80,000 kernels. A study done at the Bayer Water Utilization Learning Center, Gothenburg, NE in 2017 that measures the yield potential for five different seed sizes of the same corn product and yield differenced were determined to be not significant (Table 1).

As noted above, the size and weight of the seed did not affect yield potential. Yield potential is determined by genetics, product positioning, proper seed placement in the soil and other management practices. When purchasing corn seed, it is important to review the seed bag labels and your planter manufacturer’s recommendations. Also talk with your seed brand agronomist or representative for information on dealing with different sizes and weights of seed, planter specifications, adjustments, and proper field placement. When properly managed and properly positioned, corn seed of any size and weight can produce a successful crop.

Adjusting Planters for Seed Size and Shape

Planter settings should be adjusted for accurate seed positioning, placement, and seeding rate. When adjusted for seed size, a planter can more accurately singulate (the measurement of dropping one seed at a time) and deliver seed. Planters can deliver excessive numbers of doubles (when two seeds are attached to a cell as it rotates during planting) or skips (when there is no seed attached to the cell as it is rotating) when improperly adjusted for seed size (Table 2). Consequently, grain yield potential can be reduced by 3 to 10 bushels per acre when a mis-adjusted planter does not accurately meter the seed.1

Vacuum Planters

Adjustments can be made to vacuum planters by several different methods depending on the singulation problem. Adjustment that can be made to vacuum pressure, changing disk and/or cell size, and seed singulation devices can affect plantability and singulation. Most often it is the vacuum setting adjustment that is used to make fine adjustments after the discs are selected. Depending on the disc used, planters equipped with cell or flat disks have different requirements for adjustment. Another component to examine, regardless of disk type, is the way the disk is adjusted relative to the meter housing. Having the disk rub the housing with correct light contact can help improve singulation, reduce seed damage, and help load the planter drives, improving consistency. Using talc, most often used for vacuum planters, or a blend of talc and graphite, can help improve seed flow and drop, especially when high rates of seed treatments are used and/or when planting conditions are humid. Higher amounts of talc may be necessary, for the increased surface area, when small seed is planted. Talc should be mixed well throughout the hopper or tank to provide adequate coverage.

Vacuum Planters with Cell Disks

Planter vacuum is used to partially hold the seed in place by the cell, which is matched to the seed size and shape. Plantability is aided by matching different cell sizes to fit a given seed size and shape. Disks with cells that are on the larger end of the acceptable range for a given seed size could lead to doubles, even if the vacuum pressure is adjusted to the lower end of the acceptable range. Low vacuum pressures can increase the chance of seed being shaken off of the disk when planting over rough ground or at higher planting speeds, resulting in increased skips. To help reduce doubles and skips, disks with cells on the smaller end of the acceptable range can be used while running vacuum pressures on the higher end of the acceptable range.

Vacuum Planters with Flat Disks.

Flat disks are less sensitive to different seed sizes and shapes and can provide more consistent plantability while reducing the need to adjust vacuum pressure. Examples are the Precision Planting® eSet® and vSet® systems and the John Deere® ProMAX® 40 Flat Disk. The use of flat disks usually requires an additional component or two for singulation. The eSet® and vSet® systems utilize a floating singulator that requires no adjustments for ease of use while the ProMAX® 40 Flat Disk uses a double eliminator and a knock-out wheel. Flat seed disks may require a slightly higher vacuum level, than is used on a cell disc, because there is no cell to hold the seed on the disk. Users may benefit by visiting their equipment dealer for inspection and testing of their seed meters. Always make sure to set your vacuum planter monitor to the correct number of cells for each disk used as they can change depending on the style of disk used.

High speed planting technology for vacuum planters

With the development of planter equipment that now allows the producer to plant at increased planting speed, there are few adjustments that are needed that are different than when planting with the planters without these new developments. John Deere’s ExactEmerge® and Precision Ag SpeedTube®, among other high-speed planting systems, have been developed to now allow planters to run at up to ten miles per hour. The biggest difference between these new high-speed planters and the older planter versions is a seed tube delivery system that has been developed to use a belt system to take the seed from the meter and deliver it to the seed slice. There are also several high-speed planters that use air pressure to deliver the seed to the seed slice. Non high-speed planters commonly use gravity in a seed tube to deliver the seed to the seed slice. Since most of the other planter functions are the same the only additional planter adjustments that may be recommended would be to run increased row unit downforce and increased closing wheel force. Often a hydraulic downforce system is preferred over the air downforce system due the decreased response time with a hydraulic system. The exact settings for each system will be dependent on your field conditions and spring tillage practices. In general, expect 20-40 pounds of increased downforce and one additional notch in the closing wheel pressure when planting at speeds over 8 mph.2

When possible, it is a good idea to run all planter units, each year, on a test stand to document the meter system’s performance and to check for any mis-adjustment or excessive meter wear that can negatively effects performance.

Plantability Tests

Plantability tests have been conducted to provide planter setting recommendations for seed lots. Results are represented in terms of percent singulation (the percentage of single seeds released by the seed meter at the proper time). If the seed sensor detects two seeds where only one should be, then it is called a multiple. If the seed sensor detects nothing where a seed should be, then it is considered a skip. Therefore, percent singulation is determined by taking 100% properly timed single seed drops and subtracting the percentage of multiples and skips. Figure 2 depicts singulation data for vacuum planters with various seed sizes and shapes. Simulated planter speed was 5.5 miles per hour. Data was collected using seed harvested in 2004 through 2010 for planting seasons in 2005 through 2011, respectively.

Article Link

Sources
Nielsen, R. 1996. Seed size, seed quality, and planter adjustments. Agronomy department. Purdue University. https://www.agry.purdue.edu/ext/corn/news/articles.96/p&c9606.htm.
Darr, M. and Bergman, R. W. 2022. High Speed Planting Technology. Iowa State University. Integrated Crop Management.
Monsanto data. 2010. Brian Urban, Waterman, IL. Seed Technology Center. https://crops.extension.iastate.edu/cropnews/2020/03/high-speed-planting-technology.
Web sources verified 11/21/22
Legal Statements
ALWAYS READ AND FOLLOW PESTICIDE LABEL DIRECTIONS. Performance may vary, from location to location and from year to year, as local growing, soil and weather conditions may vary. Growers should evaluate data from multiple locations and years whenever possible and should consider the impacts of these conditions on the grower’s fields. Bayer and Bayer Cross are registered trademarks of Bayer Group. All other trademarks are the property of their respective owners. ©2023 Bayer Group. All rights reserved. 1214_74416

Estimating Soybean Yield Potential

Potential yield estimates for a soybean crop can be determined at the R5 growth stage, but estimates made at the R6 growth stage (maturity) or later are usually more accurate. Yield potential is an estimate of four components:

 

Value of Yield Potential Estimation

Estimating yield potential can provide valuable information that can be used to formulate decisions regarding storage, drying costs, and marketing. In addition, while gathering yield potential information, the field can be inspected for weed density, insect, disease, and animal injury. Evidence of water, hail, and other environmental issues also can be found. As an example, loss of population due to ponding could help influence a drainage decision.

 

Steps to Estimate Potential Yield

Number of plants/acre

The method used to estimate plants/acre will depend on how the field was planted. Counting the number of plants per length of row can be used if the soybeans were planted with a row planter. The number of plants per unit area is used if the field was planted using a small grain drill. These methods, particularly the hoop method, can be used in the spring when plants are smaller to determine plants/acre, and a record is kept for use in the fall to help estimate potential yield. The 1/1000th acre method determines plants/acre by counting the number of plants in 1/1000th of an acre (Table 1) and multiplying that number by 1000. The hoop method involves determining the diameter of a hoop, tossing it randomly in the field, and counting the number of plants inside the hoop (Figure 1). Multiply the number of plants within the hoop by the appropriate factor in Table 2 to determine the number of plants/acre. If making a hoop, an appropriate diameter is 28.25 inches, which allows for multiplying by 10,000. The hoop can be made by cutting a tube, such as anhydrous tubing, to a length of 88.75 inches and adjoining the ends. Regardless of method, several counts should be obtained at random locations across the field to estimate a final plant/acre average.

   

Pods Per Plant and Average Seeds Per Pod

The average number of pods/plant can be obtained by counting the number of pods with at least one seed on 10 consecutive plants (don’t skip small plants) at the locations where the number of plants per acre were determined.1 Divide the number of pods by 10 to get the average pod count. The average seeds/pod can be calculated by selecting 10 random pods, from the 10 plants, and counting the seeds in each. Dividing the total number of seeds by 10 provides the average seed/pod count for that location. Healthy plants can average about 2.5 seeds/pod while those under stress will have less.

The seeds/lb calculation can be challenging. A value of 2,500 seeds/lb is indicative of a healthy plant.1 Stressed soybean plants may have smaller seed; therefore, a higher seeds/lb number should be used when calculating yield potential. To estimate the average potential yield (bu/acre) use the following formula where the standard of 1 bu of soybean seed weighing 60 lb is used:

((plants/acre x pods/plant x seeds/pod) ÷ seeds/lb)) ÷ lb/bu = average bu/acre. Example: ((134,000 plants/acre x 24 pods/plant x 2.8 seeds/pod) ÷ 2,500 seeds/lb) ÷ 60 lb/bu = 60 bu/acre average.

Adding the average yields from each location that was sampled and dividing by the number of locations provides the overall estimated average yield/acre for the entire field.

Sources
1Lee, C. and Herbek, J. 2005. Estimating soybean yield. AGR-188. University of Kentucky. http://www2.ca.uky.edu/
2 2013. Corn Field Guide, 2nd edition. Iowa State University.
3 2014. Corn & Soybean Field Guide. ID-179. Purdue University Extension.
Additional Sources: Casteel, S. 2012. Estimating soybean yields—simplified. Purdue University. https://www.agry.purdue.edu/
Legal Statement
ALWAYS READ AND FOLLOW PESTICIDE LABEL DIRECTIONS. Performance may vary, from location to location and from year to year, as local growing, soil and weather conditions may vary. Growers should evaluate data from multiple locations and years whenever possible and should consider the impacts of these conditions on the grower’s fields.
Bayer and Bayer Cross are registered trademarks of Bayer Group. All other trademarks are the property of their respective owners. ©2022 Bayer Group. All rights reserved.

Checking Stored Soybean Quality

Soybean grain quality is highest at harvest. The goal for producers is to manage grain storage conditions to help preserve that quality. Soybeans that are stored under cool and dry conditions are relatively safe from fungi and insects – the primary causes of grain damage.

Poor management of stored grain can result in spoilage and loss of market grade. Storing grain at the proper moisture content, making routine grain observations during storage, and managing grain temperature are important to prevent grain storage problems. Monitoring stored soybean is particularly important during the late winter months as mild temperatures begin to warm grain masses.

Moisture

The length of the storage period influences the amount of spoilage in grain (Table 1). In general, the longer the storage period, the lower the moisture content should be to ensure safe storage.

Soybean moisture level is critical for maintaining storage quality. Soybean grain should be stored at moisture levels of approximately 12% or less. Access to an accurate moisture meter is highly recommended to regularly check moisture levels. Pay attention to the meter temperature compensation method because grain temperature can have a large effect on moisture readings. Cold grain generally causes low readings unless moisture has condensed on the surface. All moisture testers show some variability– different readings obtained when the same sample is tested more than once. To limit this effect, test each sample at least three times and average the readings. Seed soybeans should be kept at lower moisture levels. Moisture levels of 11 to 12% are recommended for long-term storage to help mitigate mold growth.

Temperature

Storage temperature plays an important role in the interaction of moisture content and grain quality in storage. Warmer temperatures require drier soybeans to maintain the same quality and allowable storage time. Controlling soybean temperature during storage is critical. Free fatty acid percentages, a negative characteristic that affects soybean oil quality, tend to increase with seed moisture, storage temperature, and time. Therefore, keeping soybeans as cool as possible in the spring and summer can help maintain oil quality.

Improved technology can help manage stored grain, but visual inspection of the grain should continue at regular intervals. Temperature cables allow for easy monitoring of the stored grain temperature at several locations, and fan controllers can operate fans according to desired air conditions. However, monitor and verify that fans are operating as desired.

Aeration

Aerate stored soybeans to maintain grain temperatures between 35° to 40°F in the winter and 40° to 60°F in the summer. These temperatures reduce mold and insect activity and moisture movement within the bin.

Accumulated moisture can be easily managed if the grain is aerated every couple of weeks. Probe the bin periodically to check for insect infestation and grain temperature increases. An increase in grain temperature is usually associated with moisture migration. Aerate to the grain to control heating or other early storage problems. If that fails, move, re-dry, or sell the beans.

Fungi and Insects

Fungi and insects are fueled by high moisture levels and are more apt to occur in grain with many damaged kernels or trash. High temperatures and high humidity set up an excellent scenario for fungi to grow. Once grain is cooled to 40°F, the likelihood of fungal growth is much greatly reduced. Fungi are the most important cause of soybean damage in storage. Insects are more likely to attack damaged beans – either from handling damage or being damaged by some other source, such as fungi.

Soybean Storage Recommendations

 


Figure 1. As winter approaches, it is important to monitor the temperature and moisture in grain bins.

Article Link

Sources
Hellevang, K. Enhancing soybean storage starts with harvest moisture. Extension Alert. North Dakota State University Extension. http://ag.ndsu.edu.
Hurburgh, CR Jr. November 2008. Soybean drying and storage. Pm-1636. Iowa State University Extension. http://crops.extension.iastate.edu.
Storing soybean. Integrated Pest Management. Iowa State University. http://crops.extension.iastate.edu.
Sadaka, S. March 2014. On-farm drying and storage of soybeans. Arkansas Soybean Production Handbook, Chapter 15. University of Arkansas Extension. http://uaex.edu.
Legal Statement
ALWAYS READ AND FOLLOW PESTICIDE LABEL DIRECTIONS. Performance may vary, from location to location and from year to year, as local growing, soil and weather conditions may vary. Growers should evaluate data from multiple locations and years whenever possible and should consider the impacts of these conditions on the grower’s fields. Bayer and Bayer Cross are registered trademarks of Bayer Group. All other trademarks are the property of their respective owners. ©2022 Bayer Group. All rights reserved. 1314_154107