Evaluation of Commercial Seed Treatments on Soybean at Three Locations in Iowa in 2014

February 10, 2015
ICM News

With funding provided from Iowa Soybean Association, 15 current commercial seed treatments from 8 companies were tested at 3 locations in Iowa: ISU Northeast Research and Demonstration Farm (NERF) near Nashua; ISU Southeast Research and Demonstration Farm (SERF) near Crawfordsville, and a farmer’s field in Roland (central Iowa). According to recommended maturity groups, public variety IA2094 was planted in Nashua and IA3014 was planted in Roland and Crawfordsville.  Replicated plots of 10 feet wide by 17.5 feet long were planted at each location. Seed treatments were professionally applied by the respective companies.


Planting dates are shown in Table 1.

Soil temperatures at planting were relatively warm (>15C (59F)) except for a few days soon after planting at Roland when temperatures dropped to 10C (55F) at Roland (Figure 1)

No effect of seed treatments on stand count or yield was detected at any location (P<0.1) (Table 2, Table 3).

The heavy rainfalls observed in June could increase the severity of SDS in the trial at Roland. None of the treatments showed efficacy for control of SDS (Table 5. Figure 2).

No differences in soybean cyst nematode (SCN) count at planting, 45 days after planting and after harvest were observed between untreated control and nematicide seed treatments. This may be attributed to low initial SCN counts, thus an effect of the nematicide treatments was difficult to detect (Table 4).

Seed treatment trials with commercial seed treatments will be repeated in 2015. All effort will be made to plant the trials earlier (April 15 – 25) in an effort to test the effect of seed treatment on early stand count and yield when soil temperatures are cooler.


Funding for this study was provided by Iowa Soybean Association. We thank Bayer CropScience, Syngenta, Valent USA, Winfield, BASF, Monsanto, Du-Pont Pioneer and Chemtura for taking part in and treating seed for this study.

Links to this article are strongly encouraged, and this article may be republished without further permission if published as written and if credit is given to the author, Integrated Crop Management News, and Iowa State University Extension and Outreach. If this article is to be used in any other manner, permission from the author is required. This article was originally published on February 10, 2015. The information contained within may not be the most current and accurate depending on when it is accessed.


Alison Robertson Professor of Plant Pathology and Microbiology

Dr. Alison Robertson is a professor of plant pathology and microbiology. She provides extension education on the diagnosis and management of corn and soybean diseases. Her research interests include Pythium seedling disease of corn and soybean and Goss's wilt. Dr. Robertson received her bach...