2018
Improving SCN managment through field research on SCN resistant soybean varieties and nematode protectant seed
Contributor/Checkoff:
Category:
Sustainable Production
Keywords:
NematodePest
Lead Principal Investigator:
Gregory Tylka, Iowa State University
Co-Principal Investigators:
Project Code:
Contributing Organization (Checkoff):
Institution Funded:
Brief Project Summary:

Currently there are three primary options for managing soybean cyst nematode: growing nonhost crops, such as corn, growing SCN-resistant soybean varieties and using nematode-protectant seed treatments. This project increases the competitiveness of Iowa soybean farmers through better and more sustained management of SCN. Resistant soybean varieties vary significantly in how well they suppress SCN reproduction, and results of assessing SCN reproduction on resistant varieties in the greenhouse do not accurately predict nematode control in the field. In this project, resistant varieties are evaluated for agronomic performance and nematode control in field experiments throughout Iowa.

Key Benefactors:
farmers, agronomists, Extension agents

Information And Results
Project Deliverables

Key Performance Indicators:
• number of Iowans who received report of variety evaluation experiments conducted in 2017 = 53,250
• number of soybean varieties evaluated in field experiments in 2018 = 216 (17 with Peking SCN resistance)
• number of different brands of seed evaluated in 2018 = 24
• number of variety trial and seed treatment field experiments conducted in 2018 = 9 and 27, respectively
• number of plots planted, maintained, soil sampled twice, and harvested in 2018 = 3,240
• number of SCN soil samples processed/counted in 2018 = 3,240 so far, with 3,240 to be done after harvest
• number of resistant varieties for which information was obtained/compiled in 2017 = 1,008 (final number for 2018 not yet known)

Deliverables and Outcomes:
• printed report of SCN-resistant soybean variety evaluation experiments distributed as an insert in the mid-January Iowa Farmer Today magazine
• newsletter articles in the Iowa State University Integrated Crop Management News (online)
• articles in the Iowa Soybean Association electronic ISA News E-Weekly newsletter

Economic Impact/Significance
• No other data exist in the United States on the effects of increased reproduction of SCN on yields of resistant soybean varieties in the field.
• Data from experiments in this project from 2001 to 2015 (supported with ISA funding from 2010 to 2015) used as the foundation of the new, national SCN Coalition.

Final Project Results

Update:
- Received seed from seed and seed-treatment companies for 2018 field experiments, designed the 2018 field experiments, and packaged and organized the seeds for the various experiments.
- Set up, planted, soil sampled, and maintained nine field experiments located throughout Iowa to evaluate the yield enhancement and nematode control provided by nearly 200 SCN-resistant soybean varieties.
- Set up, planted, soil sampled, and maintained field experiments located throughout Iowa to evaluate the agronomic performance and nematode control provided by four different nematode-protectant seed treatments - namely Aveo (from Valent), Nemastrike (from Monsanto), and Trunemco (from BASF). There were 9 experiments established for each of the 3 nematode-protectant seed treatments.
- Extracted SCN cysts (egg-filled dead SCN females), then eggs, from soil samples collected from all 9 resistant variety evaluation experiments and the 27 seed treatment experiments to determine initial SCN egg population densities.
- Began trimming the field research plots (variety evaluation and seed treatment experiments) at the 36 experiments located throughout the state in preparation for harvesting, which likely will begin on October 1, 2018.
- Contacted more than 50 seed companies and gathered information about SCN-resistant soybean varieties to use to update the ISU Extension publication titled “Soybean Cyst Nematode-Resistant Soybean Varieties for Iowa”.
- Continued to work on a manuscript to be submitted to the online journal Plant Health Progress that summarizes three years of coordinated ISA On-Farm Network and ISU small-plot experiments evaluating the agronomic benefit and nematode control provided by Ilevo seed treatment (ISA scientists Peter Kyveryga and Tristan Mueller are co-authors). Recent work on the paper included preparing yield difference graphs (with versus without Ilevo) using Iowa Soybean Association’s ISOFAST tool.

There were three main outcomes of this project in the past year, all aimed to directly benefit Iowa soybean farmers in their battle to manage SCN: 1) A comprehensive list of SCN-resistant soybean varieties was compiled and created, 2) field experiments were conducted to evaluate the potential management benefits of nearly 200 SCN-resistant soybean varieties and three different nematode-protectant seed treatments in a total of 36 experiments conducted in the 9 crop reporting districts of Iowa, and 3) results of the field experiments were published in an extension report and in a refereed paper in a scientific journal.

The United Soybean Research Retention policy will display final reports with the project once completed but working files will be purged after three years. And financial information after seven years. All pertinent information is in the final report or if you want more information, please contact the project lead at your state soybean organization or principal investigator listed on the project.