Project Details:

Title:
Improving SCN managment through field research on SCN resistant soybean varieties and nematode protectant seed

Parent Project: Improving SCN management through field research on SCN resistant soybean varieties and nematode protectant seed treatments
Checkoff Organization:Iowa Soybean Association
Categories:Nematodes, Soybean diseases
Organization Project Code:
Project Year:2018
Lead Principal Investigator:Gregory Tylka (Iowa State University)
Co-Principal Investigators:
Keywords: Soybean Cyst Nematode, Soybean Cyst Nematode - Breeding Resistance, Soybean Cyst Nematode - Management

Contributing Organizations

Funding Institutions

Information and Results

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Project Summary

The soybean cyst nematode (SCN) is Iowa’s most damaging soybean pathogen. Yield loss due to SCN can cost Iowa farmers tens to hundreds of millions of dollars in reduced soybean yields annually. The nematode has been found in approximately 74% of Iowa fields, its population densities (numbers) can increase 10- to 50-fold in one year, and it can survive for a decade or more in the absence of soybeans.

Currently there are three primary options for managing SCN:
1) growing nonhost crops, such as corn
2) growing SCN-resistant soybean varieties
3) using nematode-protectant seed treatments on soybean seeds

This project will increase 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 will be evaluated for agronomic performance and nematode control in field experiments conducted throughout Iowa. The field experiments will produce information that Iowa soybean farmers can use to select resistant varieties that reduce or slow the buildup of SCN numbers and maintain or improve soybean yields in SCN-infested fields. There is no other source of such comprehensive, detailed field information available to Iowa farmers.
Similarly, field experiments in this project with nematode-protectant seed treatments will generate information for Iowa farmers on the effects of seed treatments on soybean yields and SCN numbers. These experiments are coordinated with and complementary to ISA On-Farm® Network strip trials assessing the effects of the same nematode-protectant seed treatments.

Summary: SCN-resistant soybean varieties vary significantly in effectiveness in suppressing SCN reproduction, and the results of greenhouse testing do not predict nematode control in the field. This project provides field data on effects of SCN-resistant soybean varieties and nematode-protectant seed treatments in Iowa. There is no other source for this type of information for Iowa farmers. The project complements field research by the ISA On-Farm® Network.

Project Objectives

1) the agronomic performance and nematode control provided by SCN-resistant soybean varieties being marketed to Iowa soybean farmers
2) the effects of increasing SCN reproduction on yields of SCN-resistant soybean varieties
3) the effects of nematode-protectant seed treatments on agronomic performance and reproduction of SCN on resistant soybean varieties

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.

Progress of Work

Updated March 17, 2019:
- 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.

View uploaded report PDF file

View uploaded report 2 PDF file

View uploaded report 3 PDF file

View uploaded report 4 PDF file

Final Project Results

Updated October 3, 2018:
- 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.

Benefit to Soybean Farmers

Performance Metrics

- number of variety trial and seed treatment field experiments conducted in 2018 = 9 and 27, respectively, 36 in total
- 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 plots planted, maintained, soil sampled, and harvested in 2018 = 3,240
- number of SCN soil samples processed and counted in 2018 = 3,240 so far, with 3,240 to be done after harvest
- number of Iowas receiving a report of results of field experiments that assessed the yield and control provided by SCN-resistant soybean varieties = 53,250.

Project Years