MSU Extension Virtual Breakfast: White Mold and Tar Spot
July 29, 2021
The MSU Extension Field Crops Virtual Breakfast on July 22, 2021 focused on tar spot and white mold management options. A video of the entire presentation by Martin Chilvers, MSU field crops pathologist, is here; highlights are below.
- White Mold application window is still open as long as there are blossoms. However, soybeans are advancing quickly and this opportunity is closing fast.
- Variety resistance is still one of the most important parts of White Mold control. MSU has a White Mold nursery where they test varieties. DF Seeds tests all of our soybean varieties at this nursery to evaluate their resistant to White Mold.
- You may be seeing some dead beans in low-lying flooded areas caused by Phytophthora Root Rot. Phytophthora Root Rot is overcoming resistance genes making variety field tolerance and effective seed treatments even more important to management. DF Seeds formulates our DFender seed treatment for increased efficacy of these problematic soybean diseases in Michigan.
- Tar Spot is being spotted in the state, which is fairly early. Frequent rainfall will continue to drive disease development if they come to your area. Tar Spot can be difficult to spot early but scouting should focus on lower leaves that will be infected first. Evidence of the disease is viewable in the link.
- MSU is doing variety screening for Tar Spot at a high-pressure location. DF Seeds is participating in these trials to get information on Tar Spot resistance in Legacy hybrids. This will be shared when available.
- Just because you have not had Tar Spot before doesn’t mean you won’t get it this year. The spores overwinter on infected residue, and they will spread with the wind. Potentially spores will spread very long distances; because of this, tillage and crop rotation will not help manage Tar Spot.
