EXPERT: Check Soybean Nodulation to Determine Inoculant Efficacy

If you notice areas of your soybean field aren’t producing as well as you would expect, dig up some roots. Poorly nodulated roots may mean these plants aren’t getting the nutrients they need to produce top yields.

On average, a soybean crop needs 315 lb N per acre, about 60% of which (190 lb) goes to seed production and 40% (125 lb) goes to stover and roots. In most cases all of this need can be supplied from the environment and additional nitrogen isn’t necessary. (In sandy or low organic soils or for yields over 70 bu/ac additional nitrogen may be recommended.)

Soybeans fix nitrogen from the atmosphere when nitrogen-fixing rhizobia bacteria are present in the soil. Nitrogen fixation is a result of the symbiotic relationship between rhizobia and the soybean plant and is evident in nodules on soybean plant roots. Most studies show that between 50% and 60% of the nitrogen is from N fixation.

A well nodulated plant should have five to seven nodules on the primary root.

Checking for nodulation now can help you assess your field and make adjustments for the next crop; however, checking as early as two weeks after emergence allows you time to apply nitrogen during the season if plants are not developing nodules. (The best time to apply nitrogen in soybean is between flowering and pod fill.)

Inoculating Soybean Seed

The least expensive way to supply nitrogen to soybean is by inoculating the seed at planting.

Research in Michigan on new ground where soybeans had not been grown showed as much as a 45% yield increase for soybeans that had been inoculated compared to those that hadn’t. Michigan soils generally have higher organic matter and greater mineralization; Nebraska growers might see an even higher difference.

For fields where soybean has not been grown previously, inoculation is essential. For such fields, a soil-applied inoculant may provide greater yield potential than a seed-applied inoculant. For fields where soybean has been previously grown, either a soil-applied or a seed applied inoculant is good insurance for providing adequate nitrogen for the crop.

In fields where soybeans have been grown previously, sometimes reinoculation is necessary.

SOURCE: Robert Klein, Western Nebraska Crops Specialist, University of Nebraska-Lincoln Extension.

Leave a Reply

Seed/Biotech Stories
Seed/BiotechSyngenta Delivers Two New Winter Wheat Varieties To Eastern Corn Belt
August 6, 2014
Adding to its portfolio of AgriPro brand wheat varieties, Syngenta introduces SY 007 and SY 474 soft red winter wheat varieties. Read More
Seed/BiotechWater Optimized Seed Flowing Freely
April 1, 2014
As the demand for ag to diminish its water use while maintaining high yields and crop quality increases, three companies are leading the movement to grow more with less water. Read More
Seed/BiotechBayer Applies For Seed Treatment That Protects Against Sudden Death Syndrome
February 26, 2014
If approved, ILeVO seed treatment would be the first product to provide breakthrough protection for soybean seedlings from the soil borne pathogen Fusarium virguliforme, the fungus that causes SDS. Read More
Seed/BiotechSeed Still Central
November 1, 2013
Advancing genetics continue to make seed the crop variable that calls the shots for the season. Read More
Top 100 Articles
CropLife 100The Andersons Acquires South Dakota Plant Nutrient Manufacturer Kay-Flo
May 20, 2015
The Andersons, Inc., ranked No. 22 on the CropLife 100, has purchased Kay Flo Industries of North Sioux City, SD. “This Read More
CropLife 100North Central Farmers Elevator, Wheat Growers Unification Approved By Board, Still Awaits Member Approval
May 13, 2015
The Boards of Directors for North Central Farmers Elevator (NCFE) and Wheat Growers (WG) have voted to approve the Unification Read More
CropLife 100AgGateway’s Barcoding Initiative Progressing Nicely
May 8, 2015
According to legend (or Wikipedia), the first step towards modern bar codes came back in 1948, when Bernard Silver, a Read More
CropLife 100Pinnacle Agriculture Acquires Minnesota Retailer
April 14, 2015
Pinnacle Agriculture Holdings, LLC, ranked No. 6 on the CropLife 100,  has successfully acquired Liebl Ag, LLC in Ada, MN.  Read More
CropLife 100CHS, Aurora Cooperative Complete Fertilizer Storage, Grain Shuttle Loading Facility
April 13, 2015
CHS Inc., the nation’s leading cooperative and ranked No. 5 on the CropLife 100, and Aurora Cooperative (ranked No. 21) Read More
CropLife 100GROWMARK Acquires Missouri Refined Fuels Terminal
April 2, 2015
Bloomington, IL-based GROWMARK and Magellan Pipeline Co. have entered into an agreement in which GROWMARK will acquire the refined fuels Read More
Latest News
Bayer CropScience, ILeVO
Crop InputsISU: ‘Halo Effect’ From ILeVO Soybean Seed …
May 28, 2015
Farmers who were lucky enough to plant soybeans and spray pre-emergence herbicides in between rain events may now be seeing Read More
ManagementCorn Planting/Monsanto-Syngenta Update; New PrecisionAg…
May 28, 2015
Eric Sfiligoj and Paul Schrimpf give updates on corn planting progress, the latest on Monsanto-Syngenta rumors and preview a brand Read More
Waterhemp in soybean stubble
HerbicidesEPA Signs Off On Monsanto’s Warrant Ultra Premix
May 27, 2015
Soybean and cotton growers looking for new tools to manage weeds will have a new, first-of-its-kind option in 2016 with Read More
Palmer pigweed seedhead in cotton
HerbicidesSTUDY: Weed Diversity Primarily Influenced By Geography
May 27, 2015
The potential long-term impacts of glyphosate-resistant crops on biodiversity of the agricultural landscape have been the subject of controversy. A Read More
Seed/BiotechAgrilead Forms Distribution Alliance With Kansas-Based …
May 27, 2015
Agrilead, Inc. announces the formation of a strategic alliance with KALO, Inc. of Overland Park, KS. Through the alliance, KALO Read More
EquipmentPrecision Tank Announces A&B Welding Acquisition
May 27, 2015
Precision Tank, a specialized tank and equipment manufacturer, announced today the acquisition of A&B Welding of Thompson, IA, a manufacturer Read More
Allied Cooperative Grain Plant
ManagementTraining Program Gives First Responders Skills For Grai…
May 27, 2015
When stored grain forms hard bridges, columns and other irregularities, those working to correct it find themselves at risk of Read More
Industry NewsBASF Sponsors Space Farming Research Project
May 26, 2015
Is it possible to produce large quantities of high quality vegetables on a space station, about 320 kilometers away from Read More
FertilizerTexas Ammonium Nitrate Bill Passes Senate, Heads To Gov…
May 26, 2015
The Texas State Senate gave final approval last Thursday to new regulations for ammonium nitrate, reports The Dallas Morning News Read More
Young corn plants
Industry NewsArysta Europe Details New Organizational Structure
May 26, 2015
Arysta LifeScience Europe recently announced a new organizational structure to leverage its scale and accelerate the company’s growth in this Read More
Syngenta Sign
Eric SfiligojMonsanto-Syngenta Could Hinge On A Judgment Of Solomon …
May 26, 2015
In the bible, the reputation of King Solomon’s wisdom in matters of despite comes from a tale of one child Read More
ManagementA New Sprayer Company & UAV Research In The Spotlig…
May 21, 2015
CropLife’s Paul Schrimpf and Eric Sfiligoj talk about a Dutch sprayer manufacturer entering the U.S. with a super-sized entry and Read More
HerbicidesFirst U.S. Sale Of Enlist Duo Herbicide Made By Dow Agr…
May 21, 2015
Dow AgroSciences has recorded the first U.S. sale of Enlist Duo herbicide with Colex-D Technology. This marks the first commercial Read More
CropLife 100The Andersons Acquires South Dakota Plant Nutrient Manu…
May 20, 2015
The Andersons, Inc., ranked No. 22 on the CropLife 100, has purchased Kay Flo Industries of North Sioux City, SD. “This Read More
EquipmentNORAC Options Coming To TerraGator
May 19, 2015
Utilizing NORAC’s Standard Control technology, boom height control is now available for TerraGators with Airmax Precision 2 and Benson Booms. This Read More
Crop InputsHelena Introduces New Soil Health Product
May 19, 2015
Helena Chemical Co. is helping agricultural producers maximize yields and efficiency with the introduction of Liquid Chisel, a new product Read More
Stewardship4R Nutrient Management Planning Certification Now Avail…
May 19, 2015
The American Society of Agronomy (ASA) and the International Certified Crop Adviser (ICCA) program announce a new specialty certification in Read More
Environmental Defense Fund logo
Paul SchrimpfEnvironmental Defense Fund: Appreciating Partners
May 19, 2015
I WAS deep in the throes of preparation for the Commodity Classic meeting that took place this past February, trying Read More