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12/16/2013 - 12/22/2013

Get the Latest Information on Performance of SCN-resistant Soybeans

By Greg Tylka, Department of Plant Pathology and Microbiology

Since 1990 the Iowa State University SCN-resistant Soybean Variety Trial Program has evaluated the agronomic performance and nematode control provided by hundreds of soybean varieties advertised as resistant to the soybean cyst nematode (SCN). The work is funded by the soybean checkoff through a grant from the Iowa Soybean Association.

The SCN-resistant varieties are grown in four replicate plots in each of three experiments conducted across one of three districts (northern, central and southern Iowa) each year. The experiments also include a few SCN-susceptible soybean varieties as “checks.”  The locations of the experiments conducted in 2013 are shown in figure 1.

Figure 1. Locations of ISU SCN-resistant Soybean Variety Trial Program experiments in 2013.


Varieties also evaluated for iron deficiency chlorosis tolerance

Soybean checkoff-funded ISU research in the 1990s revealed a consistent, positive relationship between SCN population densities (numbers) and soil pH in Iowa. Greater numbers of SCN occur in fields or areas of a field with higher soil pH. And iron deficiency chlorosis (IDC) becomes a problem when soil pH is greater than 7.0. Consequently, many Iowa soybean farmers need to grow high-yielding soybean varieties that tolerate iron deficiency chlorosis as well as have resistance to SCN. 

The ISU SCN-resistant Soybean Variety Trial Program evaluates the varieties for tolerance to IDC in experiments that are separate from those in which agronomic performance and SCN control of the varieties are assessed. Results of the IDC tolerance evaluations are included in the results of the experiments.


Individual location results available now online; complete report coming in January 2014

Results of most of the individual experiments conducted in 2013 are currently available online at  The complete, printed annual report of the 2013 results will be distributed in the Jan. 18, 2014, issue of Iowa Farmer Today


More information about managing SCN

Iowa State University’s management recommendations for SCN are available online in a downloadable format, Soybean Cyst Nematode (SCN) Management Recommendations, IPM 63. An annually updated list of SCN-resistant soybean varieties for 2014 is available in PDF format online at the Iowa State University Extension and Outreach Online Store.  For more information about the biology and management of SCN, visit and


Greg Tylka is a professor with extension and research responsibilities in management of plant-parasitic nematode in the Department of Plant Pathology and Microbiology. He can be reached at or 515-294-3021.

Manure Applicator Certification

By Angela Rieck-Hinz and Rachel Klein, Department of Agronomy

Iowa State University Extension and Outreach, in collaboration with the Iowa Department of Natural Resources, has scheduled manure applicator certification training for 2014.


Commercial Manure Applicators

Commercial manure applicators can meet annual certification requirements by attending a training workshop at one of 76 locations in Iowa on Tuesday, Jan. 7, 2014. Doors open at 8:30 a.m. and the workshops start at 9 a.m. and end at noon. Commercial applicators planning to attend one of these workshops should register by Dec. 30 at the location where they plan to attend. The law requires commercial manure applicators to be certified prior to handling, hauling or land-applying manure. A complete list of Iowa locations, including one location in Minnesota and two locations in Wisconsin, is available. For those commercial applicators who can’t attend on Jan. 7, other options for certification include: 1) contacting your county extension office to determine dates available for training throughout the year, or 2) contacting you local DNR field office to schedule an appointment to take the certification exam.


Confinement Site Manure Applicators

Confinement site manure applicators can attend training at one of 63 different locations in Iowa in January and February. These workshops are each two hours long to meet certification requirements.  A complete list of training workshops is available. Confinement site applicators are reminded that if they choose to attend training to meet certification requirements, they must attend a two-hour workshop each year of their three-year license, or they will need to take and pass the remedial exam to be eligible to recertify during the next three-year certification cycle. Confinement site applicators can also choose to take the certification exam at the local DNR field office to complete certification requirements.  


Dry Manure Applicator Certification

ISU Extension and Outreach is offering eight workshops for applicators that deal primarily with dry or solid manure. These eight workshops meet certification requirements for both commercial and confinement site applicators. The only difference between this series of meetings and the regular commercial or confinement site applicator workshops is this series is geared more at solid manure handling and research. A list of these workshops is available.


Angela Rieck-Hinz is an extension program specialist and Rachel Klein is a program coordinator, both with responsibilities in manure management education for Iowa State University Extension and Outreach. Rieck-Hinz can be reached at or 515-294-9590 and Klein can be reached at or 515-294-6685.

This article was published originally on 12/23/2013 The information contained within the article may or may not be up to date depending on when you are accessing the information.

Links to this material are strongly encouraged. This article may be republished without further permission if it is published as written and includes credit to the author, Integrated Crop Management News and Iowa State University Extension. Prior permission from the author is required if this article is republished in any other manner.