Update:
Project progress from 1 April 2021 through 30 September 2021 included:
- Received seed from seed and seed-treatment companies for 2021 field experiments, designed the 2021 field experiments, and packaged and organized the seeds for the various experiments. The variety names and numbers of varieties included in the 2021 SCN-resistant soybean variety trial experiments are from Agrigold (8), ASGROW (18), Beck’s (14), Channel (7), Cornelius Seed (8), Credenz (8), Corteva/Pioneer (9), Dyna-Gro (9), Federal Hybrids (8), Hoegemeyer (11), Innotech (5), Jacobsen (4), Kruger (7), Latham (12), LG Seeds (12), Merschman (12), NuTech (14), Stine (18), Syngenta/NK (14), and Xitavo (9).
- Set up, planted, soil sampled, and maintained nine field experiments located throughout Iowa to evaluate the yield enhancement and nematode control provided by 207 SCN-resistant soybean varieties in 2021 (same as in 2020 and 21 more than studied in 2019).
- Set up, planted, soil sampled, and maintained nine field experiments located throughout Iowa to evaluate the agronomic performance and nematode control provided by 3 different nematode-protectant seed treatments - namely Ilevo (BASF), Saltro (from Syngenta), and Trunemco (from NuFarm).
- Extracted SCN cysts (egg-filled dead SCN females), then eggs, from soil samples collected at planting from all 9 resistant variety evaluation experiments and the 27 seed treatment experiments to determine initial SCN egg population densities.
- In early September, began trimming the field research plots at the 36 total field experiments in preparation for harvesting.
- In late August, we 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”. This publication will be compiled and released in PDF format by the end of October 2021.
Performance Metrics:
- number of different variety trial and seed treatment field experiments conducted in 2020 = 9 and 27, in 2021 = 9 and 27, respectively
- number of different soybean varieties evaluated in the variety trial experiments in 2020 = 207 in 2021 = 207
- number of different brands of seed evaluated in the variety trial experiments in 2019 = 19, in 2020 = 20
- number of plots planted, maintained, soil sampled, and harvested in 2020 = 3,024, in 2021 = 3,024
- number of SCN soil samples processed and counted in 2020 = 6,048, in 2021 = 3,024 as of October 14, with 3,024 more to be done after harvest is completed in October 2021
- number of Iowa farmers and agribusiness personnel who received a printed report of the variety trial experiment results in January 2020 and who will again in January 2021 = 46,000 each year
Currently there are three options for managing SCN: 1) growing nonhost crops such as corn, 2) growing SCN-resistant soybean varieties, and 3) using nematode-protectant seed treatments on soybean seeds. The results of the experiments conducted in this project help Iowa soybean farmers decide which resistant varieties and seed treatments to purchase for use in fields infested with SCN. The results of the experiments conducted in 2021 are not yet available because not all of the experimental plots have been harvested by the date of this report and none of the end-of-season SCN soil samples have been processed and counted. The report of 2020 variety trial experimental results and the 2020 list of SCN-resistant soybean varieties for Iowa were uploaded to the database with the April 2021 report..