GREENSBORO, N.C., November 9, 2026 ― Red Crown Rot (RCR) spread into new soybean-growing regions across the United States in 2026, increasing concerns about yield loss from the emerging disease. With no in-season treatment available, post-harvest is an important time for growers to identify affected fields and incorporate those insights into their 2027 management plans.
As of today, RCR in soybean was reported in 35 new counties across 8 states in 2026, including first-time reports in Iowa and Alabama.1 Iowa State University confirmed the disease in Des Moines County in August 2026, marking the first known detection in the state.2
“RCR showed up in areas this season where many growers have not dealt with it before,” said Dale Ireland, Ph.D., technical product lead at Syngenta. “There’s no rescue treatment for RCR, so identification, management and containment are key to reducing yield loss risk and protecting future soybean productivity.”
A growing threat to soybean yield potential
Complicating matters further, the above-ground symptoms of RCR often resemble Sudden Death Syndrome (SDS), making accurate diagnosis more difficult as both soilborne diseases cause interveinal leaf chlorosis, stem discoloration and root rot.
“RCR is more widespread than you may realize because it’s often confused with SDS,” Ireland said. “As agronomists and growers are looking closer, fields that were assumed to have SDS are sometimes turning out to be RCR. If you suspect RCR in your fields, collect a sample and send to your local diagnostic laboratory for analysis and confirmation.”
One way to distinguish SDS from RCR is by examining stem and leaf symptoms. The RCR pathogen causes brick-red fruiting structures on the stem just above the soil line. SDS, on the other hand, typically results in a normal white pith and tan-to-brown discoloration in the lower stem and upper root. Leaf drop can also help differentiate the two diseases. As SDS-infected plants die, the leaflets often detach and fall off, leaving only the petiole attached to the stem. In contrast, red crown rot-infected plants usually retain their dead, crisp brown leaves on the stem.
Unlike many foliar diseases that can be managed during the season, RCR and SDS infections begin below ground early in the crop’s development, shortly after germination, and continue to develop through the growing season into significant root infections. Field observations have shown yield losses can reach 15 to 80%, with typical yield losses averaging 20 to 50% across the Midwest.3
“With diseases like RCR, waiting until symptoms appear means it is too late to protect your soybeans,” Ireland said. “Understanding what occurred in your fields this season can help you make better-informed decisions before planting next spring.”
Turning harvest insights into protection
As growers begin planning for next season, a seed treatment is key to their soybean disease management strategy if there is a RCR risk.
Victrato® seed treatment is the first federally labeled seed treatment for RCR suppression. In a nine-location trial conducted from 2024-25 under moderate to heavy RCR pressure, Victrato delivered an 11.9 bu/A yield advantage over ILEVO® seed treatment in replicated field research.4
Built for the most intense pressure, Victrato tackles plant-parasitic nematodes, SDS and RCR with unparalleled potency and precision targeting, while also suppressing foliar soybean diseases early in the season. Powered by TYMIRIUM® technology, Victrato sets a new standard for soybean seed investment protection with more stopping power on the toughest soybean-growing acres.
“Harvest gives growers a clearer picture of where disease affected performance and where they need added protection from a seed treatment like Victrato,” Ireland said. “Confirming RCR now and documenting where it occurred can help growers and build a more informed management plan for the future.”
For more information about RCR and how Victrato can help protect soybean yield potential, visit WhyVictrato.com.
Media Contacts
Syngenta
frank.kminek@syngenta.com
G&S Business Communications
kwesterbeek@gscommunications.com
Web Resources
Victrato
SeedcareWins