Crop Disease Diagnosis And Plant Health: The U Of M Plant Disease Clinic Is Ready To Help

Jun 02, 2017

By Brett Arenz

The improvement of plant health (and yields) can only be successfully achieved after a clear understanding is made of what is reducing plant health in the first place. This is where the Plant Disease Clinic (PDC), can help. The PDC is based on the St. Paul campus at the University of Minnesota. It provides diagnostic services, specializing in microbial pathogens of plants. The PDC diagnoses thousands of samples each year from state and federal agencies, the agriculture and horticulture industry, and the general public. We are also part of the National Plant Diagnostic Network (NPDN) which monitors and tracks the movement of plant pathogens in the U.S.

For single season crops like corn and soybean, it is particularly important to pay close attention to plant health problems early in the growing season. Diseases that start in June will tend to have a much greater impact on final yields than diseases that don’t get started until much later in the summer. Much of Minnesota has just experienced a period of cool and wet weather, which are perfect conditions for some diseases that attack seedlings. There are multiple pathogens and abiotic issues that can cause similar symptoms and a misdiagnosis based on an incorrect assumption can lead to expensive and wasteful treatment applications, as well as not fixing the original problem!

Accurate diagnosis also requires high quality and timely samples. Plants that are symptomatic but still living are typically the best to submit. Every fall the PDC receives soybean samples submitted by growers that suspected they had a disease issue but were simply too busy during the active growing season to submit them. In many cases the dead soybean plants are impossible to diagnose as saprophytic organisms have colonized the tissues and it is not possible to be sure which organism caused the initial disease.

Source: umn.edu

Video: Spring 2026 weather outlook for Wisconsin; What an early-arriving El Niño could mean

Northeast Wisconsin is a small corner of the world, but our weather is still affected by what happens across the globe.

That includes in the equatorial Pacific, where changes between El Niño and La Niña play a role in the weather here -- and boy, have there been some abrupt changes as of late.

El Niño and La Niña are the two phases of what is collectively known as the El Niño Southern Oscillation, or ENSO for short. These are the swings back and forth from unusually warm to unusually cold sea surface temperatures in the Pacific Ocean along the equator.

Since this past September, we have been in a weak La Niña, which means water temperatures near the Eastern Pacific equator have been cooler than usual. That's where we're at right now.

Even last fall, the long-term outlook suggested a return to neutral conditions by spring and potentially El Niño conditions by summer.

But there are some signs this may be happening faster than usual, which could accelerate the onset of El Niño.

Over the last few weeks, unusually strong bursts of westerly winds farther west in the Pacific -- where sea surface temperatures are warmer than average -- have been observed. There is a chance that this could accelerate the warming of those eastern Pacific waters and potentially push us into El Niño sooner than usual.

If we do enter El Nino by spring -- which we'll define as the period of March, April and May -- there are some long-term correlations with our weather here in Northeast Wisconsin.

Looking at a map of anomalously warm weather, most of the upper Great Lakes doesn't show a strong correlation, but in general, the northern tiers of the United States do tend to lean to that direction.

The stronger correlation is with precipitation. El Niño conditions in spring have historically come with a higher risk of very dry weather over that time frame, so this will definitely be a transition we'll have to watch closely as we move out of winter.