Stephen Wegulo - Extension Plant Pathologist

Faculty Bio
Website: Wheat Disease section of CropWatch Plant Disease Management
Twitter: @wegulo2

Winter wheat in early spring in southern Nebraska — Figure 1. A grower’s wheat field in Saline County on March 22. Winter wheat is greening up across Nebraska and growers are urged tos scout for disease, given the forecasts for a wet spring. (Photos by Stephen Wegulo)

Start Scouting for Wheat Diseases March 24, 2017

The wheat-growing season is off to an early start due to a mild winter. Wheat fields are looking green from a distance (Figure 1), but closer examination reveals freeze damage in some fields caused by periods of subfreezing temperatures that occurred after growth had resumed (Figures 2 and 3).

Severe wheat streak mosaic virus in sunflower stubble — Figure 1. Severe symptoms of wheat streak mosaic in volunteer wheat in sunflower stubble in Deuel County in November 2016. Such a field significantly increases the risk of infection of wheat in nearby fields. (Photo by Gary Hein)

Growers Urged to Keep a Watchful Eye for Wheat Viruses This Spring January 25, 2017

While the mild fall promoted wheat establishment, it also favored survival of wheat curl mites, the leading vector of several viruses common to Nebraska wheat. While much of the state's wheat crop entered winter in very good condition, growers are urged to scout for viruses this spring and assess yield potential of individual fields when making management decisions.

A number of diseases were reported in wheat this fall, indicating the potential for increased diseases next spring. The author outlines a comprehensive strategy to tackle the challenge, starting this winter.

Wheat Disease Management Tips for 2017 December 9, 2016

A number of diseases were reported in Nebraska wheat this fall. In this article plant pathologist Stephen Wegulo outlines how to develop a comprehensive plan to tackle this yield challenge, starting with steps growers can take this winter.

Stripe, Stem, and Leaf Rust in Fall-Planted Wheat November 11, 2016

Stripe rust, leaf rust, and stem rust have been identified in fall planted wheat in Nebraska, extending into areas where it had previously not developed in the fall. Plant Pathologist Stephen Wegulo looks at the outbreak, conditions contributing to rust development this fall, and the economic and management issues.

Figure 1. Stripe rust on a flag leaf in a grower’s field in south central Nebraska in 2016

Fall Strategies for Managing Wheat Diseases September 2, 2016

Control Volunteer Winter Wheat and Other Weeds Now to Increase and Protect 2017 Yields, Income June 23, 2016

By far, the greatest risk of losses from mite-vectored viruses occurs when there is a summer "green bridge" of volunteer wheat emerging before harvest. This almost always occurs as a result of wheat seed head shatter from hail storms (Figure 1).

Wheat Disease Update June 10, 2016

A survey of wheat research plots in east central Nebraska found a variety of diseases, including severe rust on wheat and barley.

Wheat stripe rust — Figure 1. A flag leaf completely covered with stripe rust in a grower’s field in Nuckolls County on May 25.

Stripe Rust Increasing; Spray Your Wheat to Protect the Flag Leaf June 2, 2016

Stripe rust has significantly increased in all wheat-growing areas in Nebraska. It is recommended that wheat be treated with a fungicide to protect the flag leaf. If the incidence (percentage of flag leaves diseased) or severity (percentage of the flag leaf area diseased) is less than 50%, spraying a fungicide will significantly reduce yield loss due to stripe rust.