Protecting the Yield Potential of Rainfed Soybean Production Systems

Producing a soybean crop under dryland conditions can be challenging when rainfall is limited. Factors such as tillage, weed management, fertility, and foliar fungicides can impact yield potential. Of these, weed management is one of the most important. Weeds that are allowed to grow under limited water can quickly reduce the yield potential of a soybean crop. 

To help understand the impact of these factors, Bayer conducted an internal research trial in 2021 at Gothenburg, NE with an XtendFlex® soybean product in a non-irrigated field. The trial compared conventional and no-till tillage practices, a standard fertility program, the use of pre-emerge and residual herbicides, and the use of a foliar fungicide to help determine their impact on yield potential.

The fertility program used for each system was 50 lb/acre of phosphorus, 21 lb/acre of sulfur, and .2 lb/acre of zinc. Foliar insecticides were not applied as insect activity was below thresholds.

Systems Evaluated:

Base System: Conventional till, Roundup PowerMAX® Herbicide + AMS applied pre-emerge three days after planting, and an in-crop application of Roundup PowerMAX® Herbicide + AMS applied 4 weeks after planting.

Conventional till Residual System: Three days after planting a pre-emerge application of Roundup PowerMAX® Herbicide + XtendiMax® Herbicide with VaporGrip® Technology (Restricted Use Pesticide)¹ + OnTarget® Drift Reduction Agent + Sentris® Volatility Adjuvant was applied, an additional residual application of Zidua® SC Herbicide + Valor® Herbicide + Dimetric® Liquid Herbicide was applied the same day. Four weeks after planting, an in-crop application of Roundup PowerMAX® Herbicide was applied.

No-Till Residual System: Same treatments as conventional residual system.

No-Till Post Residual System: Three days after planting a pre-emerge application of Roundup PowerMAX® Herbicide + XtendiMax® Herbicide with VaporGrip® Technology (Restricted Use Pesticide)¹ + OnTarget® Drift Reduction Agent + Sentris® Volatility Agent was applied, an additional residual application of Zidua® SC Herbicide + Valor® Herbicide + Dimetric® Liquid Herbicide was applied the same day. Four weeks after planting, an application of Roundup PowerMAX® Herbicide + XtendiMax® Herbicide with VaporGrip® Technology (Restricted Use Pesticide)1 + OnTarget® Drift Reduction Agent + Sentris® Volatility Adjuvant + Warrant® Herbicide was applied.

No-Till Post Residual + Fungicide System: Same herbicide system as No-Till Post Residual System + an application of Delaro® 325 SC Fungicide at R3 Growth Stage.

¹_{XtendiMax® herbicide with VaporGrip® Technology is part of the Roundup Ready® Xtend Crop System, is a restricted use pesticide and must be used with VaporGrip® Xtra Agent (or an equivalent volatility reduction adjuvant). For approved tank-mix products (including VRAs and DRAs), nozzles and other important label information visit XtendiMaxApplicationRequirments.com. Applicators must check XtendiMaxApplicationRequirements.com no more than 7 days before application of this product for additional labeling, including state restrictions. Where applicable, users must comply with additional requirements found on this website.}

The results of the study showed that the base system, which did not have a residual herbicide application, had the lowest average yield of the five systems at 18 bu/acre (Figures 1 and 2). The conventional and no-till treatments with the non-residual and residual herbicide applied pre-emergence had average yields of 35.4 and 34.6 bu/acre, respectively (Figures 1 and 3). The two systems that utilized residuals applied 4 weeks after planting had average yields of 41.2 and 40.4 (fungicide applied), respectively (Figures 1 and 4).

The overall results demonstrated the positive impact of using residual herbicides to control weeds on soybean yield potential. The average yield of the two pre-emergent residual systems was 35.0 bu/acre compared to the average yield of 40.8 bu/acre for the two post-emergent residual systems. The average impact of using a pre-emergent residual herbicide was 17.0 bu/acre (35.0 bu/acre – 18.0 bu/acre).

For more detailed description of this study, please see Rainfed Soybean System or download the Channel® Field Research Book which is a compilation of Bayer research studies conducted in 2021.

Cornell weed identification. Agricultural Weed ID for New York State. Cornell University. https://blogs.cornell.edu/weedid/.

North Carolina extension gardener handbook. AG-831. 2022. NC State Extension. North Carolina State University. https://content.ces.ncsu.edu/extension-gardener-handbook/.

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.}

^{XtendiMax® herbicide with VaporGrip® Technology is part of the Roundup Ready® Xtend Crop System, is a restricted use pesticide and must be used with VaporGrip® Xtra Agent (or an equivalent volatility reduction adjuvant). For approved tank-mix products (including VRAs and DRAs), nozzles and other important label information visit XtendiMaxApplicationRequirements.com. Applicators must check XtendiMaxApplicationRequirements.com no more than 7 days before application of this product for additional labeling, including state restrictions. Where applicable, users must comply with additional requirements found on this website.} 

^{ALWAYS READ AND FOLLOW PESTICIDE LABEL DIRECTIONS. It is a violation of federal and state law to use any pesticide product other than in accordance with its labeling. NOT ALL formulations of dicamba, glyphosate or glufosinate are approved for in-crop use with products with XtendFlex® Technology. ONLY USE FORMULATIONS THAT ARE SPECIFICALLY LABELED FOR SUCH USES AND APPROVED FOR SUCH USE IN THE STATE OF APPLICATION. Contact the U.S. EPA and your state pesticide regulatory agency with any questions about the approval status of dicamba herbicide products for in-crop use with products with XtendFlex® Technology.}

^{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.} 

^{Products with XtendFlex® Technology contains genes that confer tolerance to glyphosate, glufosinate and dicamba. Glyphosate will kill crops that are not tolerant to glyphosate. Dicamba will kill crops that are not tolerant to dicamba. Glufosinate will kill crops that are not tolerant to glufosinate. Contact your seed brand dealer or refer to the Bayer Technology Use Guide for recommended weed control programs.}

^{XtendiMax® is a restricted use pesticide. Not all products are registered for use in all states and may be subject to use restrictions. The distribution, sale, or use of an unregistered pesticide is a violation of federal and/or state law and is strictly prohibited. Check with your local dealer or representative for the product registration status in your state. Channel® and the Arrow Design® and Seedsmanship At Work® are registered trademarks of Channel Bio, LLC. Bayer, Bayer Cross, Roundup PowerMAX®, Roundup Ready 2 Xtend®, Roundup Ready 2 Yield®, Roundup Ready®, VaporGrip®, Warrant®, XtendFlex® and XtendiMax® are registered trademarks of Bayer Group. LibertyLink® and the Water Droplet Design® is a trademark of BASF Corporation. Valor® is a registered trademark of Valent U.S.A. Corporation. All other trademarks are the property of their respective owners. For additional product information call toll-free 1-866-99-BAYER (1-866-992-2937) or visit our website at www.BayerCropScience.us. Bayer CropScience LP, 800 North Lindbergh Boulevard, St. Louis, MO 63167. ©2023 Bayer Group. All rights reserved.}