You Are Here: Management Updates 2003 Archive October 30, 2003

Date: October 30, 2003
Category: Diseases
Subject: New Fungicide Available, Rust Disease

Insignia, a new fungicide in the strobilurin chemical group now available:
A new fungicide has just been registered with the EPA. Insignia™ has the active ingredient pyraclostrobin and is a member of the QoI/strobilurin group that also includes Compass and Heritage. Therefore, consider all three of these fungicides as the same way of attacking fungal pathogens and rotate to different chemical groups to prevent or delay resistance.

Insignia™ is a localized penetrant that is active against many common turfgrass diseases including Pythium blight and fairy ring. It has a label for dollar spot suppression although it is not recommended as a stand-along product for this disease. The online fungicide chart has been updated to include this new product. Please note the footnote numbers following the name pyraclostrobin which give more information at the end of the chart. To download the chart, visit the Online Publications section of this web site.

Rust
We are approaching the season for rust disease, especially on Kentucky bluegrass and perennial ryegrass. There are a number of different rust diseases, but they all produce numerous pustules of powdery orange spores that give the diseases their name. Rub a white kleenex on the leaf blades to see the orange powder if you are not sure of the diagnosis.

Factors that increase rust: low N, wet weather (fog or long lasting dews that keep water droplets on leaf blades), dry soil, compaction, cold temperatures. It takes 10-14 days for the spores to form after infection, so frequently mowed grass will not develop rust. If the plants are slow growing and infected leaves are not mowed off, rust may occur. It does not kill the plants, and the orange spores will die over the winter. Even badly rusted turf will be healthy when it begins to grow in the spring. No fungicides are recommended.

- Submitted by: Dr. Gail Schumann