Farm Progress is part of the Informa Markets Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them. Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Serving: MO

Fungal diseases prominent in 2021 crops

Daren Mueller, Iowa State University, Phytophthora root and stem rot
DYING OFF: Phytophthora root and stem rot is a soil-borne fungal disease caused by Phytophthora sojae. It causes seed rot and damping off of seedlings. It can affect plants at various stages of growth. It typically ends in plant death. The fungal disease showed up in Missouri during the 2021 growing season.
The MU Plant Diagnostic Clinic releases the first-half results of crop disease and pest samples.

Weather during the first half of the year proved favorable for fungal diseases in many row crops, according to samples submitted to the University of Missouri Plant Diagnostic Clinic.

The MU Plant Diagnostic Clinic reopened Feb. 1. Since then, it has received 214 samples, including physical samples, walk-in samples and digital samples.

Plant disease diagnoses were identified in the majority of the samples. Only three samples were for insect identification services. And the clinic reports no samples for weed identification.

Of 211 disease diagnosis samples, 15 samples were suspected to have herbicide injury, and 12 samples were confirmed with winter injury, indicating that off-target chemical damage — as well as cold injury —played important roles in affecting plant health this year, says Peng Tian, director of the clinic.

The samples submitted to the clinic also were categorized based on the crop types, with ornamentals being the largest sample category with 71. It was followed by field crops at 47 samples and turf at 19 samples.

Problems for row crops

The heavy rainfall early in the season increased the incidence of crown and root rot diseases for wheat, corn and soybeans. The MU Plant Diagnostic Clinic confirmed 12 cases of Phytophthora crown and root rot diseases on soybean samples, five cases of corn Pythium crown and root rot, and two cases of Rhizoctonia rot and eyespot disease on wheat.

These diseases are primarily because of high moisture level in the soil, Tian explains, adding that the prolonged cool and wet conditions also triggered many foliar diseases or head blight diseases in the field crops, such as wheat leaf rust, wheat scab, wheat blotch, soybean frogeyes leaf spot, septoria leaf spot, corn gray leaf spot and southern rust.

Tops diseases/pests in 2021

Tar spot disease is a relatively new disease to Missouri and has been confirmed in four counties to date. So far, no bacterial or viral diseases were detected from corn and soybeans in the field this year.

Get your crops tested

For appropriate diagnosis, the MU Plant Diagnostic Clinic can help you confirm if your plant has a disease. Farmers can visit the MU Plant Diagnostic Clinic online and review submission guidelines before submitting your sample. Farmers can also take photos and send them to [email protected].

For a step-by-step process on submitting samples, watch the short YouTube video below:

For sample submission and fee payment, farmers can visit the new online submission system at Fill out the submission form online using your computer or mobile device and make payment online securely with a credit card.

Or farmers can download the submission form at Fill it out and send it together with your sample and payment. Check or money order is accepted. No cash.

Source: University of Missouri IPM, which is solely responsible for the information provided and is wholly owned by the source. Informa Business Media and all its subsidiaries are not responsible for any of the content contained in this information asset.
Hide comments


  • Allowed HTML tags: <em> <strong> <blockquote> <br> <p>

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.