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

Bob Harveson
Bob Harveson

Harveson Receives APS Distinguished Service Award for Region

August 28, 2019
The Distinguished Service Award recognizes outstanding effort in teaching, control of a significant plant disease, or service to the science of plant pathology. In nominating Harveson, his peers touted his work across multiple areas.

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Crop Diseases Confirmed by UNL Plant & Pest Diagnostic Clinic

June 14, 2019
Report of the diseases reported in samples submitted to the UNL Plant and Pest Diagnostic Lab from May 15 to June 14 for corn, soybean, and wheat.

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Goss's Wilt of corn

Nebraska Plant Pathology: A Culture of New Diseases

January 23, 2019
Though relatively small, UNL's Department of Plant Pathology has played a significant role in the discovery of many economically important plant diseases, including most recently, a new fungal pathogen causing Fusarium head blight of wheat. This article is from the 2019 Nebraska Crop Management Conference Proceedings.

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Specialty Crops Disease Update

January 10, 2019

The occurrence and distribution of plant pathogens are long known to be strongly influenced by the environment. We see evidence of this concept every season on specialty crops in western Nebraska, and 2018 was no exception.

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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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