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Barley stripe rust (BSR) has occurred in Idaho each year since 1993 but has
caused little or no economic losses in the state to date. In 1995 it was detected for
the first time in western Washington and western Oregon and is currently
considered to be well established there. Thus, we now have a source of inoculum
(spores) upwind of our barley fields and are at greater risk of economic losses than
in the years prior to 1995.
We need to treat BSR as a serious threat. Many of you can recall the wheat stripe
rust epidemics of the late 70’s and early 80’s (and a few of you can recall those of
the 60’s) when susceptable wheat varieties like Fielder and Fieldwin were popular.
Wheat stripe rust and BSR are very similar diseases, and there is a good chance
we will see some very yellow barley fields (due to BSR) at some point in the next
several years.
Virtually all of our barley varieties are susceptible to BSR, although six-row types
tend to be a little more susceptible than two-row types. Yield losses may be in
excess of 50% in severe cases or may even be 100% as occurred in several
California fields last year when growers didn’t bother to harvest severely diseased
fields.
Tilt fungicide is still the material of choice for BSR control. Recall the label restriction for Tilt; it
may not be used after awn (beard) emergence. Novartis (formerly Ciba), the
manufacturer of Tilt, has applied to EPA to permit application after awn emergence,
but has not received approval, yet.
Symptoms of barley stripe rust.
The information on this page came from a article prepared by Robert Forster.
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