Strip Rust Confirmed in Hazelton

Stripe rust is confirmed in Hazleton, ID, on the soft white winter wheat variety Brundage. So far only in one field, but we will keep monitoring the development. Winter wheat in Jerome area was boot to flowering, but no stripe rust was seen on WB528 and SY Ovation. Root disease (possibly Rhizoctonia) and maybe nematode pressure caused stunting, root damage, yellowing of plants in fields where cereal crops were planted three years in a row.

Overall, we are not seeing many foliar fungal diseases in wheat or barley. We are seeing winter grain heading out in the Magic Valley areas, with mostly good to excellent conditions with appropriate irrigation. There were some fields of winter barley and winter wheat with BYDV symptoms evident this spring. BYDV is a problem in areas where corn production is highest, due to the fact the corn is a “silent host” for BYDV - in other words, corn hosts the virus but does not show symptoms or yield declines. The aphids coming off of maturing corn in the fall will then fly to emerging wheat and barley fields, carrying the virus with it. Insecticidal treatments will significantly reduce the impact and spread of BYDV. http://www.cals.uidaho.edu/edcomm/pdf/CIS/CIS1210.pdf

Additional problems in dry land winter wheat are showing up that indicate poor, dry soil conditions and high pH contributing to overall poor health. Calcareous outcroppings result in winter wheat that is stunted, yellow, and has poor tillering. Areas that have better fertility will fare better, but such areas should be treated prior to planting with a balanced fertilizer regime including sulfur, phosphorus, and possibly micronutrients, which become unavailable at high pH soils. If possible, calcareous areas could be treated with compost and / or manures to boost soil microbial activity and organic matter. Fungicidal seed treatments will benefit dry land plantings, which usually are deeply seeded. While dry land plantings are seeded deeply to access scarce soil moisture, stressed plants will be susceptible to root diseases and have fewer tillers. Typical Rhizoctonia symptoms were seen last week in deeply planted (and stressed) seedings of spring wheat in the Newdale area. Barley mealy bugs were found near a field edge of winter wheat (Utah 100) south of American Falls, probably creeping in from the field edge where grassy weeds were the preferred host.

Springs grains did get planted early, and are showing some signs of nutrient deficiency and Pythium damage. Untreated barley planted deep in cool wet soils are especially showing this disease problem. Wireworms are widespread from dry land areas in eastern Idaho to irrigated production areas in Aberdeen to Twin Falls. Spring grains are anywhere from late tillering, to 2-4 leaf stage, depending upon location.

Juliet Marshall, Ph.D.
Associate Professor, Cereals Pathology and Agronomy

Idaho Falls R&E Center
1776 Science Drive Suite 205
Idaho Falls, ID 83402
208-529-8376 office
208-390-4859 cell

http://www.extension.uidaho.edu/scseidaho/

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