Iowa State University The Rust Report
Preventative vs. Curative Fungicides

We have received several questions about selection of fungicides, especially with regards to deciding between “curative” and “preventative” fungicides. People want to know if they should be applying a strobilurin fungicide, triazole fungicide, or a premix of both. 

To fully understand how a fungicide reduces disease development, we need to understand the disease cycle of a foliar pathogen. Foliar pathogens are polycyclic, which means that many disease cycles can occur in a single season. A disease cycle consists of the following steps: infection, colonization, symptoms and spore production. The period from infection until symptoms are first seen is known as latent infection.

The complete article can be viewed on the ICM News site.