From Ned Tisserat, CSU Extension Specialist and Professor, Bioagricultural Sciences and Pest Management
Ned sends out information concerning wheat diseases in the state on a routine basis. To subscribe to this email, please email Ned at Ned.Tisserat@ColoState.EDU.
A quick update on the wheat disease situation in the Great Plains. As you are probably aware, wheat leaf rust and stripe rust must survive the winter in green tissue. Thus, it isn’t often (if at all in the case of stripe rust) that we see these rusts overwintering here in Colorado. Instead these rusts usually survive the winter in Texas and then are blown northward during the spring as the wheat resumes spring growth. The movement and development of these rusts in states to the south then impacts what we see in Colorado later in the season.
As of now, there are reports of leaf rust and stripe rust in the very southern parts of Texas. This isn’t unusual and doesn’t necessarily portend trouble for us. There are no reports of significant diseases in Oklahoma yet. It is still very dry in much of west Texas and Oklahoma, and unless things change, it will slow development of rust in those locations.
Some growers may be thinking of applying fungicides in conjunction with herbicide applications this spring as ‘insurance’ against potential disease development, even though diseases are not currently present. Over the years, I have seen no compelling, consistent data from Colorado to support these early fungicide applications except perhaps in irrigated wheat with high yield potential and where powdery mildew or other fungal leaf spots are already present.
Extension Specialist and Professor
Colorado State University
Plant Sciences 1177
Ft. Collins CO 80523