SITUATION

The seed industry has been challenged this year with a level of seed borne diseases that haven’t been seen for many years. A long, wet harvest with many delays provided an opportunity for diseases to infect seed pods and, in some instances, to infect the seed itself. Reports are coming out showing that this year’s seed soybean crop is frequently testing positive for the fungus Diaporthe, which causes Phomopsis seed decay. Phomopsis seed decay causes a lower than normal germination rate in seed.

FACTORS TO CONSIDER

Due to the poor environmental conditions a lot of fungal growth has happened. Anytime there is fungi on the seed, the seed starts to deteriorate as the fungi feeds on it. Less than optimum germination scores are widespread across the entire industry this year, especially on soybeans grown in the Midwest during the 2018 season.

• Lower germination: Phomopsis-infected seed will have a lower probability of germination when planted. Diminished seed quality and reduced seed vigor, germination and emergence are all consequences of seed decay. Seed decay can also reduce seed test weight and oil content.
• Low visual appearing seed: Seed decay is characterized by cracked, shriveled seed with white chalk-colored mold on the seed surface. Other visual observations that may be seen this year are obvious discoloration of the seed, some green seed, some darker seed. The seed is simply not very eye-appealing this year.
• Winter storage: Winter storage of seed can help to increase germination rates, due to the fact that under dry storage conditions, the mycelium of the fungus will die, improving the seed quality.
• Spring soil conditions: If soil conditions are wetter and cooler than normal, this could drastically improve both the survival and stand count of the plants.
• Adjusting seeding rate: Depending on the germination scores it may be necessary to adjust seeding rate to account for lower germination.

ACTION PLAN

According to past Iowa State University research, appropriate seed treatments can increase germination rates. Given the progress and development of fungicides, germination rates could be further improved, given the right mix. Growers should check soybean bag tags carefully for germination rates, calculate seeding rates appropriately and pick the right fungicide seed treatments in the spring.

We recommend using Legend Seeds YP Pro Soybean Treatment to help improve germination rates and to protect the seed from other early season soil-borne diseases. YP Pro: Soybeans and YP Basic: Soybeans have THREE modes of action to help deliver a healthy stand in the spring.

SUMMARY

Many growers will want to have their seed treated with a fungicide to increase the chances of germination and prevent seedling diseases. Contact your Legend Account Manager or Legend Sales Agronomist for additional information on the protection offered by YP seed treatments.

RESOURCES

https://crops.extension.iastate.edu/cropnews/2018/12/should-you-use-fungicidal-seed-treatment-lowquality- soybean-seed
https://www.dtnpf.com/agriculture/web/ag/news/crops/article/2018/12/06/lower-soybean-seedgermination- 2019

Visit our Seed Treatments page to learn more about the products we have available