Winter wheat growth in Nebraska is progressing at a steady pace, with most fields now green with little or on disease; however, growers are urged to continue scouting their wheat for early signs of disease as current and forecasted wet weather this spring is likely to lead to severe disease outbreaks.
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)
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).
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)
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.
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 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.
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).
