Earlier this year we discussed how to get ahead of white mold in 2020. In that article, we discussed the makeup of white mold, the conditions that make the disease thrive and the prevention tactics growers could apply to help prevent it from affecting their fields this year. Over the past few years, especially with the wet year we had in 2019, white mold has begun affecting more fields, sometimes resulting in as much as 15 to 20 percent yield loss. With an estimated 75 percent of soybeans planted and 52 percent emerged, now is the time to begin scouting for white mold to see if it will impact our fields again this year. Here are some tips for white mold detection and a refresher on how to prevent it in the coming years.
White Mold Detection
Stine Regional Sales Agronomist Tony Pleggenkuhle notes, “If you get wet weather during flowering of soybeans and it stays that way and you have a heavy canopy, you have the potential to see white mold.” An early and heavy canopy acts as a barrier, trapping in white mold spores and encouraging its spread in the soil below.
As for timing of its appearance, growers should start scouting around the R1 to R2 reproductive stages of the plant. “White mold usually shows up when soybean plants blossom and are ready to set pods,” notes Tony. “Early in the season, you could find the white mushrooms that look like little trumpets that release the spores that get in through the blossoms of the plant and infect it that way,” he adds.
Watch this video where Tony discusses other signs of the disease and how to scout for it this season.
Tony Pleggenkuhle – White Mold Detection
https://vimeo.com/354690728/cdb85e5235
It’s also worth noting that the University of Wisconsin recently updated their Sporecaster app, a great tool to help predict white mold and provide management strategies for the disease.
The University of Wisconsin-Madison notes, “Sporecaster is designed to predict the probability of white mold apothecial presence.” The app uses GPS coordinates to determine if weather in the area has been favorable for the development of white mold apothecia during the relevant reproductive stages of the soybeans in specific fields.
Learn more about the app and how to download it here.
White Mold Prevention
There’s no resistance to white mold and, unfortunately, once it’s detected in your fields, there’s really nothing you can do to stop it in season.
“The most important thing you can do to prevent white mold from hitting your fields this growing season is to plan ahead,” notes Tony Lenz, Stine corn technical agronomist. “Evaluate your fields and make the necessary preparations to proactively respond to the potential threat of white mold.”
To prevent white mold, you need to know if a field has a history of the disease. If it impacts your fields this year or has in years past, it’s good practice to plan for it affecting your fields in 2021. Growers can consider specific soybean products that boast white mold tolerance, soybean seed treatments, placing a bio fungicide on their fields in the fall or early spring, and exploring wider row configurations and lower planting populations, to name a few. We’ve also seen some promising results applying fungicide at the R1-R3 reproductive stages.
Stine Corn Technical Agronomist Tony Lenz discusses different tips for white mold prevention in this video.
Tony Lenz – White Mold Prevention
https://vimeo.com/354670843/251c898000
White mold can do a lot of damage to yield, and growers need to be proactive in scouting for it this growing season and planning ahead for next year. For more information on white mold and how it can affect your fields, contact your local Stine sales representative.