Soybean iron deficiency chlorosis

decrease font size  Resize text   increase font size       Printer-friendly version of this article Printer-friendly version of this article

Soybeans in North Dakota always look green as they emerge. Iron in soybean is mobile in the plant until the first trifoliate leaf emerges. At that time, for some mysterious reason iron becomes immobile in the plant and has to be taken up fresh for each increment of added tissue. Therefore, soybean that has been green up until now will suddenly become chlorotic if soil conditions are favorable for its development once the first trifoliate leaf emerges.  Soil conditions that are essential for IDC development are carbonates. Soils that have pH higher than 7 normally contain measurable carbonates. Soils with pH less than 7 do not have carbonates and IDC is not possible. Yellowing of soybean in acid soils is caused by something other than iron. This year, that yellowing could be caused by waterlogged soils, loss of S or failure of inoculation in first-year soybean fields. Manganese deficiency is unknown in the field in North Dakota. Be advised that manganese application to IDC fields can intensify IDC by competing with iron for uptake.

IDC is minimized by choosing a tolerant variety, using an ortho-ortho-EDDHA fertilizer at planting, such as Soygreen™, planting in wider row spacings, using a cover crop at the time of soybean seeding, and not applying N to the soybeans or at least choosing fields with lower residual soil nitrate levels. IDC is made more severe when soils are wet (a current problem), cool (not a problem anymore), soluble salts are high, or residual nitrate is high for natural reasons or because N was applied with another crop in mind and the field switched to soybean for planting date reasons. Some growers might have used an EDDHA product at seeding and still have intense IDC symptoms. Manufacturers are not required to put the type of chelate on their label. According to Dr. Goos in our department, many EDDHA fertilizers he has tested have lower percent ortho-ortho-EDDHA in their formulation compared to Soygreen. It is the ortho-ortho-EDDHA that is particularly effective against IDC, not ortho-para-EDDHA. Many formulations of EDDHA have significant and often dominant ortho-para-EDDHA instead of mostly ortho-ortho.

Herbicide application will intensify the IDC symptoms briefly, but it is not the root cause of the problem. If IDC is seen in the field, there is no spray that can help. The grower needs to ride it out and soil drying will eventually reduce the problem in most areas of the field if a tolerant variety was grown.

Buyers Guide

Doyle Equipment Manufacturing Co.
Doyle Equipment Manufacturing prides themselves as being “The King of the Rotary’s” with their Direct Drive Rotary Blend Systems. With numerous setup possibilities and sizes, ranging from a  more...
A.J. Sackett Sons & Company
Sackett Blend Towers feature the H.I.M, High Intensity Mixer, the next generation of blending and coating technology which supports Precision Fertilizer Blending®. Its unique design allows  more...
R&R Manufacturing Inc.
The R&R Minuteman Blend System is the original proven performer. Fast, precise blending with a compact foot print. Significantly lower horsepower requirement. Low inload height with large  more...
Junge Control Inc.
Junge Control Inc. creates state-of-the-art product blending and measuring solutions that allow you to totally maximize operating efficiency with amazing accuracy and repeatability, superior  more...
Yargus Manufacturing
The flagship blending system for the Layco product line is the fully automated Layco DW System™. The advanced technology of the Layco DW (Declining Weight) system results in a blending  more...
Yargus Manufacturing
The LAYCOTE™ Automated Coating System provides a new level of coating accuracy for a stand-alone coating system or for coating (impregnating) in an automated blending system. The unique  more...
John Deere
The DN345 Drawn Dry Spreader can carry more than 12 tons of fertilizer and 17.5 tons of lime. Designed to operate at field speeds up to 20 MPH with full loads and the G4 spreader uniformly  more...
Force Unlimited
The Pro-Force is a multi-purpose spreader with a wider apron and steeper sides. Our Pro-Force has the most aggressive 30” spinner on the market, and is capable of spreading higher rates of  more...
BBI Spreaders
MagnaSpread 2 & MagnaSpread 3 — With BBI’s patented multi-bin technology, these spreaders operate multiple hoppers guided by independent, variable-rate technology. These models are built on  more...

Comments (0) Leave a comment 

e-Mail (required)


characters left

Grain Storage Systems

Behlen Grain Storage Systems offers large capacity bins with diameters from 16’ to 157’ and capacities exceeding 1,500,000 bushels. All ... Read More

View all Products in this segment

View All Buyers Guides

Feedback Form
Feedback Form