Cereal Disease Forcast for East Idaho for 2013

It will be difficult to forecast disease for the upcoming year, as everything depends on mother nature and the production practices of each grower. I have no control of either! However, I can give an opinion of what I expect to see in wheat and barley.

Winter crops, especially winter barley, may be at risk of damage from Barley Yellow Dwarf Virus (BYDV). I have seen some pictures this spring of winter barley with symptoms that resemble BYDV, but until we obtain samples and confirm with serological and / or molecular techniques, we cannot say for sure. However, with confirmed incidence of BYDV last year (2012) in winter barley, it is very likely that we will see it again. Damage from BYDV (if not severe) can be somewhat mitigated by preventing crop stress – provide appropriate fertility and irrigation.

With the frosty and cold conditions this spring, we will probably see quite a bit of frost damage on winter cereals. Keep an eye out for yellowing and browning of the leaf tips. As a result of frost damage, we may also see bacterial blight and / or black chaff.

Root diseases can be reduced with crop rotation away from cereals and practices that promote healthy plant growth, such as the use of starter fertilizers and fungicidal seed treatments. While planting cereals has hit full swing, we are still having very cold conditions. Cool, moist conditions will result in disease pressure from Pythium, which is regularly seen in cool wet springs, especially in barley. Metalaxyl-based seed treatments will help keep these fungi at bay, and are highly recommended. Dry conditions will also be an issue with a risk of seed decay caused by various soil-borne fungi. The impacts of dry rot or dry seed decay will be significantly reduced by broad spectrum seed treatment fungicides.

 Some foliar diseases can also be reduced with crop rotation. The things that CAN’T be controlled will be those diseases related to excessively dry planting conditions, or cool and wet seed beds. In addition, the occurrence of foliar diseases that ride the wind or sneak out from residue of other crops like corn are very hard to estimate. However, I expect stripe rust will be minimal and similar to last year, will occur mostly in late-planted (susceptible) spring wheat.

Of major concern to me will be the occurrence of Fusarium head blight (FHB) in spring wheat following corn. FHB can and does occur in any rotation, even wheat following canola, but the risk is very high when spring wheat follows corn. In this situation, PLAN on spraying a triazole fungicide (no strobilurins or strobilurin – triazole mixes) at 50% flowering.

Additional information will be available via the PNW Pest Alert System (PNWPestAlert.net) and also via email alerts. If you wish to be placed on my cereals email alert list, please send me an email at juliet.marshall@uidaho.edu.

 

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/