Plant Disease Management for Agricultural Crops

Information in this section was developed by the Extension Plant Pathology Team in the University of Nebraska–Lincoln Department of Plant Pathology. It's designed to help crop producers, agricultural consultants, extension educators, and other agricultural professionals in Nebraska identify and manage plant diseases, a major yield limiting factor for many Nebraska crops. The most critical issue for profitable management of plant diseases is obtaining a correct diagnosis. In any given year, the question is not whether diseases will occur in Nebraska but rather which diseases will occur and at what incidence and severity.

Many factors influence disease development in plants including hybrid/variety genetics, age of the plant at the time of infection, environment (e.g., soil, climate), weather (e.g., temperature, rain, wind, hail, etc.), single versus mixed infections, and genetics of the pathogen populations. Due to variation inherent in these factors, diagnosis of plant diseases can be difficult at the early stages of disease on individual plants as well as at the early stages of an epidemic. However, for many diseases symptoms do become diagnostic at some stage of disease development and a reasonable level of confidence can be placed in diagnoses based on these symptoms.

Contact the University of Nebraska-Lincoln Plant and Pest Diagnostic Clinic in Lincoln and the Panhandle Plant Disease Diagnostic Lab in Scottsbluff for assistance with diagnosis or confirmation. For many diseases, symptoms become diagnostic and a reasonable level of confidence can be placed in diagnosis based on symptoms.

Information on the pathogen, symptoms, favorable environmental conditions, management, and related links for each disease are listed by crop:

Plant Diagnostic Clinics

UNL offers two Plant Diagnostic Clinics — one in Lincoln and one in Scottsbluff. For all samples please submit a Sample Submission Form.

Lincoln Plant and Pest Diagnostic Clinic

Located in the Department of Plant Pathology, this facility provides diagnostic services in plant pathology, entomology, horticulture and weed science. In addition to accurate diagnosis of your pest problems, you will be provided with current information about the disease and management recommendations. Learn more about services and how to submit a sample.

Scottsbluff Panhandle Plant Disease Diagnostic Lab

Located at the Panhandle Research and Extension Center at Scottsbluff, this lab focuses only on plant disease identification. Most of its samples are of sugar beets or soil samples from sugar beet fields; however, diagnostic services are provided for any diseases encountered in the Panhandle. Learn more.

Plant Disease Video Library

Thirty videos on identification and management of corn and soybean diseases are available at UNL CropWatch on YouTube. Go to the field with UNL Plant Pathologists Tamra Jackson-Ziems and Loren Giesler as they show you what to watch for to correctly identify and manage Nebraska crop diseases.

Related Articles

Cowpea wilt
Figure 1. A two-year study of diseases in Nebraska cowpea, also known as black-eyed pea, found a wilt, similar to bacterial wilt in dry bean, to be most common. (Photos by Bob Harveson)

Cowpea Bacterial Wilt ― An Old Disease in a New Crop October 9, 2018

As growers in western Nebraska look at new pulse crops to integrate into their rotations, a UNL plant pathologist works to identify possible disease threats. Cowpea (black-eyed pea) is being studied now.

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Stalk rots in corn
Stalk rots in corn

Corn & Soybean Diseases Confirmed Sept. 13-28 September 28, 2018

Various corn stalk rots lead the list of corn and soybean diseases confirmed by the UNL Plant and Pest Diagnostic Clinic September 13 - 28. Diseases are listed by reporting district.

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Frogeye leaf spot on a soybean leaf

Diseases Confirmed in Corn and Soybean July 26-Aug. 15 August 17, 2018

Corn and soybean diseases confirmed by the university's Plant and Pest Diagnostic Clinic from July 26 to August 16.

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Leaf symptoms of brown stem rot of soybean

Crop Diseases Confirmed in Corn and Soybean July 16-26 July 26, 2018

Corn and soybean diseases confirmed by the university's Plant and Pest Diagnostic Clinic July 16-26.

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Loren Giesler, new Head of the UNL Department of Plant Pathology

Loren Giesler Named Head of Plant Pathology Department July 23, 2018

Loren Giesler has been named head of the Plant Pathology Department at the University of Nebraska–Lincoln, effective Sept. 1, 2018. A long-time contributor to CropWatch, Giesler is a professor and extension plant pathologist in the department.

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