Issue No. 21, Article 8/August 12, 2005
New Field Assessment Key for Asian Soybean Rust Management
So you've been scouting for Asian soybean rust. Now what? The first steps to effective disease management are scouting and identification. If you scout for soybean rust, and find it and have it identified, then what? Your next question should be "How much disease do I have?"
To determine the percentage of infection, you will need to make observations of the leaves in comparison with a known standard. We have developed just such a standard to help producers assess what percentage of infection is present on soybean leaves. This assessment card shows the actual amount of a soybean leaf covered by rust pustules at several key levels of infection. Assessing the percentage of infection for rust diseases is not an easy task. Even seasoned evaluators use assessment keys to keep themselves on track when determining the percentage of infection.
You can buy this new tool, with or without a 20X pocket magnifier, at Agronomy Day on August 18. An order form can also be downloaded here.--Suzanne Bissonnette and Dean Malvick